Let's try this again. Bigger Brakes Cannot Stop You Faster - Bigger Disc Leverage and more
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Here's an interesting little piece of information. The amount of heat released by an average car during a single braking instance from a speed of 90 km/h is enough to boil two liters of water in just three seconds. All stock systems on all cars today are capable of doing this at least 4-5 times before brake fade starts occurring. This means that you can accelerate from 0 to 90 panic brake to a stop then accelerate to 90 again panic brake again and repeat this cycle at least 4 times before the slightest amount of brake fade can be measured. And even once brake fade starts it will be small and gradual and getting your stock brakes to fade to a point where they can't lock up the wheels and trigger ABS is next to impossible. This means that driving on the street cannot overpower the stock braking system. In fact if you ever need multiple panic brakes in a row while driving on public roads than there's something very wrong with your driving.
A lack of braking force does not exist on vehicles. Issue number two is that increasing braking force further cannot reduce your stopping distance.
And this is because your tires are the only thing on your car touching the ground...they are the only point of contact between your vehicle and the road surface. Once your overpower the grip that your tires provide there is nothing else left to overpower. Once the tire locks up and starts sliding increasing the brake force further will achieve nothing. Increasing the brake force via increased leverage or increased clamping force cannot increase the grip of the tires.
Increasing braking force further cannot reduce your stopping distance. And this is because we already have more than enough braking force to lock up the wheels. The comments on my previous video is make it obvious that many people associate brakes primarily with friction and torque....but a much better approach would be to perceive brakes as heat sinks. This is what they do. They convert the motion of the car or kinetic energy into heat and then dissipate this heat into the surrounding air.
Now we're going to compare three different cars to illustrate the extent to which modern cars really don't have an issue with braking.
The first one is the Mclaren Senna which is an 800 horsepower hypercar with absolutely amazing brakes state of the art carbon brakes. It has 390mm discs and 6 piston fixed calipers in the front. It gets from 0 to 100km/h in 2.6 seconds. The second car is the Mazda MX-5 ND has 280mm disc brakes and single piston floating calipers in the front. The 2.0 liter model gets from 0 - 100 km/h in just under 7 seconds. The third car is my very own 2009 Toyota Aygo has 247mm discs and single piston floating calipers in the front. It gets from 0-100 km/h in 14.2 seconds.
So as you can see we have staggering differences in brake systems and acceleration times. But not so much when it comes to braking distances. The Senna manages to come to a stop from a speed of 100kmh in 30 meters. The ND MX-5 manages 33.8 meters. I did a little test with the Aygo and did 10 panic brakes from 100 km/h and I managed an average of 35 meters.
So the McLaren Senna has 57% larger brake discs than the Aygo and has six times the number of caliper pistons. It is also 446% faster from 0 to 60 than the Aygo but it is only 16 % faster from 60 to 0.
So why is this the case? Why doesn't a million dollar hyper car dramatically outbreak a cheap little city car? The reason is that technology has long since reached the sensible limit of braking force.
Getting to a stop from 100 km/h in 35 meters takes less than 3 seconds and this in turn exposes you to forces of nearly 1G. Which is the limit of what the average driver can sustain on their body and still retain full control of their car.
Engineers are more than capable of making vehicles with ridiculous stopping distances. For example the F2004 which is Ferrari's formula 1 car from the 2004 season can come to a stop from 100km/h in just 16 meters. That's more than 2Gs of force. Formula 1 drivers are highly trained athletes capable of taking this load easily. On the other hand 2Gs would make many average drivers loose control of their vehicle. In fact F1 cars can generate as high as 5Gs of force when braking hard from high speeds. That's the sort of deceleration that can make some people pass out.
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#d4a #bbk #brakes
This man is a gift to the car community.
He's a proper car enthusiast with an engineering mind. Great that he can make nice videos too!
He's saving me so much money! 😂
oh yea definitely he is
For sure
As a professional race car driver NASCAR breaks are just as critical as acceleration on a paved short track .
So in summary larger rotors and calipers can help shed off heat which will help delay or even prevent brake fade under extreme use such as a race track, but they do not decrease stopping distance. Also a video on master cylinder ratios would be nice.
Yes, the tires are the most important thing, but the brakes come right after that.
Size matters for braking the disc itself, it's a question of leverage, but it's useless as brake power is always higher than the tyre ability to brake. So your car would skid anyway once you overpowered the tyres ability to stop the car. If you have ABS, it'll make no difference. I don't think he mentions that because it would need further explanation. So technically the disc stops better if it's bigger, it wouldn't give any advantage in stopping the car. That's why cars or motorcycles have different brakes at the front and at the rear, they're all calibrated according to weight distribution, tyres, suspensions, etc.. ABS interrupts and reactivates the brakes not to have you car skid, that means brakes are already too powerful, no point in making them more powerful. In racing condition is different, standard brakes are not calibrated to constantly be under pressure, therefore you need something that keeps them at the optimal temperature even if you brake hard all the the time. Whether you do that with bigger brakes or better ventilation, that depends on many factors. E.G.: on motorbikes the front is quite big and has holes for better cooling, on cars the front one can't go beyond a certain size, so it normally has two parts stuck together that lets air flow in between these two parts for cooling purposes.
I only view it as bigger disks means less fade. On my S4 And A4 using oem parts I can go from either 321 mm or the A4 288mm disks to the 360mm D3 and D3 W12 385mm rotors. All in the name of looks.
Yes, bigger brakes will not you stop faster, but make you slow down faster for example from 200-150 km/h where ABS is not involved
you are absolutely wrong cause stock brakes can still easily lock up your wheels even at a 200 km/h so it still makes no difference between stock and bigger brakes. Bigger brakes only have impact when you drive on race track where you have to brake every corner, so your brakes wont overheat as fast@@jakub.686
Great set of videos. I teach high performance driving to many new drivers and we always recommend they save their money by not upgrading to larger brakes (for a couple years at least while they are learning to drive). Pads? Yes. Fluid? Yes. Brake ducts? Yes. All for the same reason: heat management. Want to brake in shorter distance? Upgrade the tires.
Tires and damping control. Better tuned shock absorbers help control weight transfer and can absolutely help decrease stopping distance when tuned PROPERLY for the vehicle and paired with stickier/wider tires
Many years ago, I was told that THE best performance upgrade you could buy for cars or bikes was fuel, or to put it another way more time behind the wheel, or if you really need it breaking down, improving the driver. A better driver won't use the brakes as often or as much, without sacrificing speed, because they understand the capabilities of their chosen ride. Excellent video as always ... 🙂
@johnsantiago7836 is 100% correct. If your brakes are sufficient to lock up your tires (or engage the anti-lock) then the limiting factor is your tires. All the rest is about heat management. Another unpopular but true thing about brakes... drilled and slotted rotors are a marketing gimmick. With old pads that off-gassed a lot when they overheated drilled and/or slotted rotors helped but they are good for nothing except marketing today.
@@ukemike1well I had the same opinion, but upon further inspection, it is not the case. Drilled or slotted disks can and will improve braking distance on HARD breaking, just because they self clean better and they gain a tiny cross sectional area that helps them cool a bit faster (not by a lot of course, and this isn't the main reason as to why they are "better" than non drilled ones). You can see an experiment garage 54 did, but we also did some simulations in my engineering school, and yes, just because they can clean themselves better, the callipers can grab the rotors more efficiently without slipping. The gains while kinda small, they are noticeable. Are they worth the extra 80-xxx$ more than the regular ones? Absolutely not, and THAT makes them a marketing gimmick. Do they have some benefits tho? Yes
@@JellyBean-ed2uq But they give cool points. As such, I too fell for slotted rotors.
The people who got upset had just spent thousands on a big brake kit.
Remember y'all - this is the man who described what is happening with each "stu-tu-tu" noise in your turbo. You will never beat this final boss
which video was that? I'm very intrigued now.
@@ytdood i second that notion
@@ytdood it was in boost school
Has this dude ever tried brembos? They stop more
@@griffon2-6 kzhead.info/sun/daqRecuFfJFriHk/bejne.html
The dude didn't insult the people who treat him "idiot" while proving his point. Real humility
I think the best insult is proving your point to them while not saying any insult because maturity wins harder
He even gave them them all the possible benefits of the doubt
more maturity than humility imo
Even though he's still wrong. His reasoning sounds legit, in theory. But in real life he leaves out a lot of factors that have a much bigger effect than the slight mechanical advantage of larger diameter rotors.
@@awo1fman Note how you didn't name a single one, or demonstrate how that's going to outperform a device that's already limited by the tires. Since they're all capable of locking the tires and triggering ABS. In real life, he gave you several factor that might make you think bigger brakes are helping. He even left out the psychological effect that people expecting something are more likely to feel something, even if it isn't there.
Brilliant video! Spot on! I’ve been an Automotive Engineer for the past 14years, most of that time being in Brakes Engineering, working for Renault, Ricardo UK, Bosch Engineering and recently I moved to Jaguar Land Rover and I can confirm that ‘bigger’ brakes will only do one think, in the vast majority of cases, they will disturb the brake feel and the modulation as the brakes will tend to lockup faster as you very well stated in this video. Also if they are aftermarket brakes don’t be surprised if they are ‘noisy’. Unless you are racing, I wouldn’t even touch the stock brakes. We spend years getting the system sized correctly and the adequate pedal feel. More importantly most of the stock brakes are quiet, because of a very good reason we literally spend over two years in Brakes Refinement testing by making sure that the brakes are quiet, many millions of pounds are spent in that respect. With aftermarket brakes you cannot have the same level of Brakes Refinement as the aftermarket doesn’t have access to the same level of dyno, CAE and vehicle testing as an OEM does. Most of the braking systems are oversized anyway, as most OEMs design the braking system around the AMS test, which is not even a legislative requirement. The AMS test is extremely severe (10 consecutive brake stops from 100kph to 0) and it’s not a realistic use case. Consequently we end up with very big brakes and more importantly very heavy brakes. Therefore do yourself a favour and unless you are racing and you need the thermal capacity, then do not waste your money on shinny new ‘big’ brakes.
I don't think AMS test is extremely severe. Imagine going down a mountain road. You might keep the brakes engaged for a lot of the trip going down. Would really suck if the brakes start to fade. Also imagine the brakes aren't brand new, but on a 20 year old car, that was maintained by an average person, and that doesn't really care about fanatic maintenance. Most people do maintenance on brakes only when weird sound appear, especially on older cars.
also a case that i have been peripherally involved with - you have a 18 year old daughter who loves horses and takes two horses in a fully loaded float to the local dressage show up a 1600 foot hill the return trip is a 4 mile windy descent the vehicle is an automatic and no one has taught her about low range in the 'box - she encountered a runaway situation towards the bottom of the hill and did not have the experience or presence of mind to save the situation @@antonio94
100 -0 is extremely severe? 😂😂😂🤡
@@antonio94 If you keep brakes engaged on a downhill road you need to go back to driving school.
@@antonio94 why aren't you pushing that clutch in and selecting a lower gear? You shouldn't be driving down a mountain using only your brakes. Quite the opposite.
I bought a car with Brembos fitted from new, the sort of things people upgrade to. I managed to cook them on the track to the point of having no braking no matter how hard I pushed. Not just brake grade, but brake vanish!! Came home, threw out the rotors and pads and upgraded those. Same brakes, same fluid, but better heat dissipation from the rotor and oars that were more heat tolerant and I now have a car that feels no different to drive, but the more I brake, the better it stops as heat gets into the system. So upgrading the right components, not the whole braking system, is where you’ll get the most benefit. Great video once again, love your stuff!
My previous car I added a brake kit purely because after a few track sessions I'd have issues with the sliders. Even after rebuilding the calipers, this wasn't the issue with fixed multi pot calipers. I actually got to try the car with the same brake compound in good condition with and without big brakes. I definitely wasn't able to do as many laps before fade but pedal feel was better on the standard setup again like D4A said it messes up the MC ratio somewhat. With the BBK fitted the pedal was definitely slightly mushier, not terribly but enough for you to notice. The fix for it was to switch to a different MC, but while it was worse than the standard setup it wasn't outright dangerous. Funnily enough on the trackday with the standard calipers a lot of people left in the afternoon and the track was very quiet. This meant me doing way more laps than I normally would and out of all the braking components it was the fluid that went first as I had a long session and all of a sudden I went to brake and the pedal pretty much went to the floor. The car still did slow down enough so I let everything cool down and came in. Turns out I'd boiled the fluid (Fresh ATE Superblue when you could still get it) before I'd reached the limits of the pads/discs/calipers. One other benefit was a reduction in unsprung mass that actually improved general feel on the front end as the 4pot wilwoods were much lighter than the standard cast iron slider calipers. Stopping distance however was identical, on track the only thing that noticeably improved braking distances for me was going from a regular summer tyre to an actual track tyre. My current car has a factory Brembo option which I'm going to be fitting instead of an aftermarket kit, it's definitely worse on the unsprung mass side but there won't be any brake bias or MC issues. I may not need this but to be honest after you've had any sort of loss of braking during track driving I'd rather have more safety margin than not.
You don't need to upgrade to ride on the streets, that's the point. On track of course you need better heat dissipation, as you're constantly breaking to almost locking, and generating tons of heat in the way. But in the street, unless you're a public danger, you don't need bigger brakes. However, more leverage can lead to a better braking sensation so if that's your objetive, do it. If you just want to brake more, put on wider tires, as i've made in my car, which will also make your car steer better.
Personally, I appreciate the effort you put into explaining things and enjoy your videos.
Thank you!
👍👍
Totally agree
@@d4a the brakes will stop you faster than the tires?
@Trevor Brannon because the would get to hot and fail
I thought everyone knew braking distances were determined by the tyres? Oh well, excellent explanation for the physics though! 👍🏼
Nope, the people who lack knowledge of the laws of physics only look at the size of the brakes, say with full conviction that "bigger is always better" and then call other people dumb for "not understanding how brakes work."
Also determined by the driver.
And the brakes, as I discovered when the left rear brake line on my 73 Datsun burst like an old garden hose.
Imo if you can lock your wheels and leave skidmarks then you need better tires. If you do experience brake fade however, only then do you upgrade your pads and rotors.
@@tjroelsma put so 10” wide race tyres on a 1300kg car and you’ll likely see a lack of braking power due to increased tyre grip.
The amount of times I've given up trying to explain to people that upgrading their brakes won't make their car stop any faster, it'll just make it easier to lock up their wheels when braking. People don't quite get it, even though everybody does understand tyres can only grip so much before they slip, it's like they know A and they know C but they can't quite work out how B figures into it.
Oh my, it's as though you understand physics!!!😮😂 Don't waste your time educating those who are so dedicated to ignorance.
You sir have consistently been my favorite automotive KZheadr for like 5 years. I seriously think you’re the best. Thank you
Big respect not only for posting a follow up, but for maintaining your professionalism when others couldn't. This is a huge reason why this channel is my #1 when it comes to understanding automotive engineering with the intent of educating others - your commitment to providing content of exceptional quality shows in every video! Keep up the excellent work, and I can't wait for the next one! 👍
He made another video because he had a serious mistake in the first video @ kzhead.info/sun/dt2BZdyHmqWOq6s/bejne.html He showed a cross-section of the tires without considering the other dimension. Skinny and wider tires have the same 2D contact patch area! Google: "discount tire contact patch" for an illustration. Performance vehicles often use wider tires. This does not necessarily increase the size of the contact patch but rather changes its surface shape. Reshaping the contact patch makes it more efficient for accelerating, braking and handling.
@@johngalt1199 Most people do not realize this. Of course tire pressure and tire sizes do have some effect. But for proper inflation pressures and similar tire construction it is only the shape, not the actual contact area, which really changes.
It is amazing to see how nervous and rude (to use polite terms) people can become when contradicted; but it is even more surprising to see your patience and kindness in re-explaining the arguments, despite all the insults given by uncivilized people
Totally agree. I was expecting something like "to everyone who called me an idiot, apparently you're all idiots" or else. But this coldblooded smart guy is incomparable to those "comment experts". Gentle, tactful, yet accurate and cogent. Love his vids
@@randomguyjustpassingby although,i bet some people would find it insulting to be told to seek help because they got worked up over a brake video. there are aways those kind of people that finds problems in any case or circumstance with another person,regardless of the topic.
Threat responses are never pretty
It's like some of those people vastly overestimate their knowledge on a subject, and don't want to learn if the facts are contradictory. It's their loss though ¯\_(ツ)_/¯
I started with the same counterpoint of larger = more leverage. But your explanation is one of a PhD haha thank you for sharing the truth and saving me money
I fitted larger brakes to my old, pre-ABS car and I can report improved feel and better braking - on the track! Vented and grooved rotors with newer style sliding calipers has made the car far better to drive on the track, but on the street, the difference in driving is negligible. Totally agree with the info in this video
And his explanation is wrong in the real world for a lot of reasons that he absolutely overlooks - or possibly deliberately ignores.
I am stunned by this video. I always had this curiosity but never searched for an answer. Thank you for doing this clip. Wow
A video about brake bias, master cylinders, etc. would be great 😊
Agreed!
Seconded.
Thirded lol
+1
Yes!
I appreciate that you don’t waste our time with jokes, or with constantly interrupting the video with other stupid and loud clips to make a joke. I appreciate that I can watch it without constantly bringing the volume up and down. And most of all, I appreciate the knowledge and fantastic explanations. Man you’re awesome.
Did you miss the hilarious people sliding on ice??? ;-)
Agree 100%, there are other channels which are good but too many unhappy jokes, channels with a lot more subs. I don't know if that type of humour appeals to Americans, but to my knowledge that doesn't work in Europe. This guy is from Europe and so am I. I don't find those jokes that funny and there's a time and a place. Following an explanation and hearing puns and cheap sex jokes every 2 minutes makes me want to change video
@@23max232323232323 absolutely! Once or twice per video is more than enough for an internationally accepted joke
I ended up on this video trying to figure out how my 37“ mudding tires work on pavement 😹 I learned so much and this was wonderfully done! Thank you for touching on the importance of learning your car stock first 😭 it makes everything so much easier!
This is a great video! I've had this conversation with so many people. Tires are more important to stopping than brakes, especially on a sports car. I only upgraded my brakes on my RX-7 once I improved my driving skills to surpass what my tire/brake set-up could handle. I upped the tires to a track tire, and then upgraded the brakes to match the upped grip. I didn't go BBK though, I only upgraded pads and discs to slotted.
Definitely make the video of piston size vs master size ratios.
I put a larger master And it was excellent improvement. Even such that when the reservoir is bone dry there is enough fluid in the cylinder for full-braking.
@@fastinradfordable I hope you have also increased the area of your pistons accordingly. Otherwise you now have less brake pressure than before.
@@kilianortmann9979 wrong
@@cornishcat11 Please elaborate. Pressure is the same at Master cylinder and Brake Pistons. Thus force is proportional to inverse Area. Increase piston area increase brake force, increased Master cylinder area decreases brake force.
@@kilianortmann9979 no the master is SMALLER then the caliper
Sometimes people can't accept the harsh reality 🤣🤣 Btw a brake system series is a great one
What harsh reality? You're drinking the click bait kool aid if you think your stock break system will be as good as a 3,000K big break kit because this guy says so.
@@Zeriel00 it will for the first 5 minutes on track, next!
@@Zeriel00 guy is really just trying to justify his purchase so he doesn't have buyers remorse anymore. only thing an expensive big brake system is gonna do is look better, have slightly longer lasting pads, and probably last longer for both rotors and calipers
@@Zeriel00 ok if you know everythjng, please explain how a bigger brake system will stop you quicker when the abs system is already reducing braking force in a panic stop with a stock braking system
@@Zeriel00 so we should ignore statistics and believe you, got it
I've learned more amazing facts about engines and cars from this Man in the last 3-4 years than basic to sophisticated knowledge since I was in my teens. Things that, as an engineering physicist, I should have known. Or figured out on my own. But "motorhead lore" and what seemed to be complicated but "common sense" had polluted my mind. If he says something about motor vehicles, I believe him. And then go back and figure out why I've looked at it wrong for decades. As an aside. I drove big heavy American V-8s from my teens (1974 -1987). Many were used and cheaper models and had front disk brakes and rear drum brakes. Although I started with a disc/disc 1953 Ford Flathead. I don't know if differential brake wear caused me a problem. I lived and went to school in LA for 4 years (1980-1984). To numerous to count times, I would come to partially blind freeway corner at ~65 mph only to see traffic at a dead stop ahead. I would stomp the brakes in my 350 V-8 1973 Monte Carlo. The rear drums would immediately lock up. But not the front discs. The car would end up, what seemed like, 80 degrees sideways with me steering into the turn. Totally in control directionally. Lots of screeching. I could, literally, control the sideways angle of the car by modulating brake pressure. I'd keep it sideways, in total steering control until I was pretty certain I would stop and gradually let off on the brakes. First slowly, and then immediately, it would snap back to straight forward. I was never trained at all in this type of driving. I just happened a lot in LA back then. The horrors of the 55 mph days. Going 55 mph on a LA freeway would get you killed. Many of you trained drivers are probably saying, duh? It happened often enough and was so amazing to me that I developed skills in using that technique. My previous cars were also heavy only with drum/drum brakes. This never happened with them. Obviously before ABS systems, did this mean that the proportioning valve was not correct or out of adjustment? Could I have corrected it to make rear lockup less likely? My personal observation is that a front heavy V-8 car stopped faster when controllably traveling sideways? Am I incorrect about this? I've always been leery of front disc/rear drum brake cars since then. Comments and thoughts are welcome. After that, I bought a used 1973 350 Corvette Convertible with front and rear discs plus 4 wheel independant suspension. Life was Grand. When I was 25 years old. Just Graduated Med School. I learned what a "women magnet" car really was. It was "chick magnet" back then. But I didn't want to offend any Karen's who police KZhead for micro aggressions. Only one more personal anecdote and a question. I promise. From 1982-1986, I also occasionally drove my girlfriends early 80s Toyota Tercel 4 cylinder low power and light weight 4 door. Narrow skinny tires on ~14" or less, steel rims. All factory parts. Not a "hotrod" car or one that inspired spirited driving ever. That car spun itself ( my interpretation) or I spun it >360 degrees on ~ 5 occasions. Always at normal driving speed. Every time, the road was coated with a wet watery mist on top of a normaly dry oily road surface. Never touched the brakes until it was out of control. I guess this is why F1 drivers get the Big Bucks? My first front wheel drive car, I realized that just letting off the throttle in a normal speed wide sweeping turn simulated only putting on the front brakes. The opposite of a RWD car. Instantly Initiating the out of control spin. I was lucky as no other traffic was ever around. An instant lesson in oversteer. I believe it was a dangerous vehicle. I've driven many later 1980s FWD cars without any problems. Any ideas on what was done to rectify this vehicle based design problem? Before ABS, traction control, etc.?
Really love your way of explaining, I was shocked when you said people in your comments thought bigger brakes helped stopping distance "under normal road use"
Towards the end I can definitely say that the single best performance part I've ever bought for a car were lighter wheels. Lower unsprung weight dramatically improves handling and lower rotating mass has an exponential effect on acceleration and braking at higher speeds. At legal speeds though it doesn't make much difference.
Should help with comfort too over high frequency bumps provided one doesn't have overly stiff springs and dampers.
This actually helps with fuel efficiency in urban areas a lot too. A lot of energy, therefore power and fuel, is spent on rotating the wheels instead of accelerating the car when you are accelerating. If you remove much of that weight you aren't going to use as much energy to spin the wheels up to speed. This has a compounding effect the faster you go.
That makes a lot of sense. Thats why magnesium wheels are more desireable? Is aluminum lighter than magnesium? I know magnesium ones are more expensive. Man this stuff is deep. I love learning about it. It helps with figuring out all my builds.
Best car mod I done is switch from 195mm wheels to 215mm. It does not sould like big change but improvement in handling is hudge.
The main rotating masses on a car, apart from brake rotors, wheels & tyres. Is: The Engine, clutch, flywheel, transmission/gearbox, Propshaft, diff & driveshafts!
That was the most genuine “seek help” I’ve seen😂 he really does seem like a cool dude.
I learn a lot of new stuff every time I watch your videos. Thanks for the time and effort!
Thank you for the support, I sincerely appreciate it
The laws of physics are the only ones one cannot break. They say: as long as the braking system is able to stop the wheels from turning, which is the case for all cars out there, “stock” or not, the only limitation to the braking force & hence distance is the tyres’ grip. Sticky, warm, broad tyres are the only ones which’ll do the trick, nothing else. Well done, mate, keep it up! 👍
Except that it’s not. Take any showroom car, drive it to top speed, slam the brakes and the ABS won’t kick in. By the time half the speed has been scrubbed the brakes will be so hot they start fading already and the ABS never kicks in.
I would love to hear about the master cylinder to brake caliper ratios. Love these videos.
yes plsss
Yes
That's basic physics/math. The difference in bore size vs piston sizes give leverage and multiply the force coming from the pedal. The pedal on its own do also multiply the force that's made by the foot
Yeah, bring it on!
yeah that would be an interesting topic.
Love your work. Love how you deal with people who have no idea. Please keep doing what you do. I really enjoy your videos.
This was suggested to me again for some reason. Once you modify the car from stock to make it faster with more grip it is possible to overwhelm the stock braking system where it will fade before you have thrown off all of the speed. For instance a giant truck where someone goes from 26" tires to 44" tires there may not be enough mass in the stock brakes to not fade in a panic stop from 120kph to 0kph.
A video describing an argument I've had it dozen times. And everyone telling you the bigger breaks are better have bald tires. You're the man liked and subscribed.
The first part and this video changed my perspective towards the ideas I had on what would improve the braking performance on a streetcar. Thank you. Appreciate your efforts on creating such high quality content
they wont stop you faster once.... but on the track, bigger brakes will stop you faster more than once.
@@reddyfreddy like after brake application number 5 from 200 kph to 0 kph in a row in 3 minutes
Thanks for spreading truth. It just shares how few people actually understand how cars actually work. They get so excited by modifying thier car, they stop using common sense.
I wouldn't really caulk this up to common sense. First thought of "how to stop faster" is "oh the brakes stop you, so bigger brakes must be better at stopping you".
Using "common sense" is usually the first, best way to get something (you know nothing about) all wrong.
@@apex107lrp Not if you know how to look at something critically. Shows most folks can't use critical thinking skills.
@@SturdivantRacing126 If that were true engineering degrees wouldnt take years.
@@Brandon_Tyr The time it takes to understand something and the thinking process to understand it are mutually exclusive. You can understand something new every day and take years to master the topic.
Tires and then suspension are generally going to be your biggest inprovements to braking time. Once youve improved the tires though, you add more traction, and thus it CAN help to improve the brakes (more pistons or more leverage or both). It CAN help. It probably wont in many cases, but hell, it wont generally hurt much of anything to my recollection, and a lot of the better quality brake kits, and pads, and such have better brake fade characteristics under heated conditions. (See also racing) Another thing you should take into account, if you throw on 20s or something ridiculous onto your small car youre adding a lot of extra rotational energy to those tires, and thus it is often worth it to throw in better brakes to handle it.
Firstly, thank you for the wonderful refresher of the technology I learnt at college, nearly 50 years ago. Right from the start I was thinking 'heat dissipation' and tyres' grip. The original 'classic' Mini had drum brakes, always capable of stopping the wheels turning if properly maintained. The upgrade to discs (from the Cooper versions) was unnecessary unless used for competition. The later fitment of discs by Rover was to remove the need for adjustment of the drums every 3000 miles, not for any additional braking effort. I must however take you to task. The most important feature of any car in amking it safer, is the driver. Sadly, that is the most difficult part to improve, so we go with ABS, EBA, etc.
Big brake kits will typically improve your brake feel and ability to modulate the brakes. People confuse this with "better" or "stronger" brakes. Like you said, the tire stops the car, not the brakes. Stock brakes have enough grip to lock up the tires. That is all the brake you need. Anything beyond that is all about brake feel, or ability to dissipate heat for repeated high speed stops (like track use).
Think you nailed it. Bigger brakes allow for more brake durability during track use - because of brake fad. So you can still stop at the limits of your tyres when brakes pads are working at 50%.
Stronger brakes are overrated, all it does is lock up your wheels faster. But they are handy (they don’t overheat as fast) if you’re slowing down from very high speeds. :)
@@angelgjr1999 Completely backwards, weaker brakes tend to lock-up after reaching a certain point. Stronger brakes when set up properly allow better modulation and control.
And they last longer due to bigger pieces of materials, force put through bigger area. Like for my brake pads I pay 10$ and they last damn a lot.
@@xorbe2 no, Angel is completely correct! As is this video.
I definitely want to see a comprehensive video on upgrading a brake system the right way. Seeing the ratios and what would actually increase performance. I am looking to upgrade my brakes, but have no reason to as of yet. I intend to do light track driving and would upgrade instead of replacing my brakes which are running about 10k miles from their end of life.
Brake pads. Maybe slotted or vented rotors but not really worth it if you are doing light track days; just getting some track pads on new stock rotors will do wonders (if you need them properly).
what you want to do is dissapate heat from repeated high speed braking. So things that manage heat better are brake pad compound, rotors with higher vent count (maybe a bit thicker as well), brake ducting, high quality high temp brake fluid. Now to take advantage of ur clamping force you need more traction, I.e a well setup suspension and proper tires.
If you do track driving bigger brakes might be beneficial to counteract brake fade by achieving better heat decapitation, also they look cool 🤷🏻♂️
If your doing track days get some high heat dot 3-4 brake fluid in the system, put the stainless steel braided brake lines if you’d like, there not always needed, go get your self a set of pads meant to handle the heat and abuse for a race track when you get the right pad you will stop incredibly faster than you thought your stock brake system could handle. I recommend ether getting the brake rotors lathed so there fresh for a new pad, or get a set of nice slotted rotors to help give a better bite into the brakes,
Upgrade your stuff in stages, your car is like a science experiment on the track, if you go and upgrade the tires and the suspension and then everything else all at once how will you ever know if your modifications actually made you faster on that track, star off by upgrading your brakes, if you notice that your out performing the tires then upgrade the tires, then you might find your out performing the sway bars upgrade those, but don’t do everything at once.
I remember discussing a fancy new air filter someone had bought, i explained to them that the car in question makes no more power with no air filter, as the intake was the restriction as such stock was not a restriction at all. They countered by insulting me and stating they could blow through the fancy filter with their mouth more easily so it was impossible not to make more power.
This has been illuminating! I'd love to hear more about brake bias and ask the other stuff you mentioned!
Do the brake bias video please! That would be fun to learn about
It's pretty obvious, really. The forward weight transfer while braking means that the front tires have more traction and can take more braking force. The master cylinder applies more hydraulic force to the front. If all wheels got the same, the rear wheels would lock up (bad) while the fronts are not yet achieving maximum braking potential.
Screw that! He should do a video on why my brakes get "Ring around the rotor" on spanking new pads/rotors on stock 4 pot Bremboa
Would love to see more videos in how braking systems work and how to calculate brake bias/ hydraulics etc!
100
Yes please!!!
+1
Thank you for the follow up video. I think you did a much better job, addressing why you won’t experience a big improvement by upgrading your brakes. Out of all the channels you are my absolute favorite for breaking down these normally controversial topics into very simple, straightforward concepts and data. I think a lot of people would have to just be ignorant or denial to argue otherwise
Thank you for educating people with proper arguments. I had opportunity to drive 2019 911 GT3 RS once on Grobnik track and I was brave enough to push brakes from 200kmh the hardest I could. That was out of this world and the most of the drivers are not prepared with what comes with strong brakes. And the example with bike brakes I know from my experience - just putting the money into high quality brake pads for rim brakes is way stronger and more responsive than disk brakes.
Anytime anyone is able to brake hard enough to cause the ABS to kick in, that means the car's theoretical limit of braking ability (for a given tyre size & particular road surface) has been achieved. ;) 15:45 at this video sends a very good warning as well. Fully second this. Always choose a good aftermarket BBK from a reputable mfg that makes a specific kit for your chassis. Universal mix-n-match brake system are best reserved for ground-up track car builds.
Now I kind of want a video about aftermarket air intakes! That would probably break the internet.
Simple answer to that is: only do it if your running a vacuum much higher than stock, ooorrrrr you have a car that was gimped by legacy emissions systems like carb and such. Which is not the majority of cars produced in the last 10 years or so.
Personal experience, If you only do the open air intake without heat shielding you will lose power. If you make it into a cold air intake with heat shielding, you’ll probably still lose power. If you have a turbo or compressor which you have upgraded, then an cold air intake will work. Noticed it myself when the stock new intake was sucked into the box after upgrading a supercharged mini r53 and the car needed a lot more air. In my mind it gave it a bit more torque and made it faster. Never did real tests though but the sucked in airfilter was for me a give away that it’s better to upgrade after putting a lot more horsepower into a car.
@@Vincentf30 all it does is increase throttle response by 1% but if done with a good cold kit it "could" improve top end performance....for about a week. sucking air from the fender is not all bad unless it sucks air from the engine already like a miata
Try Engineering Explained. He did a video on it like a decade ago.
@@thatslegit Its also about smoothness of airflow into the intake - the more the flow is disrupted and bounces around, the more the temperature increases and the less dense it becomes. A differing factor could be the air filter itself and what the type of setup it is (air box/pod filter etc) From personal experience, i had better results with an OTR (over the rail) intake from the manufacturers performance brand (Holden/HSV) in comparison to an aftermarket "cold" intake coming from the fender.
I've always known this. I've never been able to explain it to my friends cuz they're dumb. I'm glad we have you on our side to help us explain this
This channel is an absolute GOLD MINE to the world of automotive enthusiasts...
I would love to see a video on brake bias and other little brake system quirks like that :) It really sucks to see how negative people can get in the comments of your videos, you've been extremely informative, and I guess people sometimes take it personally when it turns out their mods were not that well thought out, this video was a very good response though.
But damn they look good stopping the same! 😉
Great Video! Track stuff is fun but the best reason brake upgrades is definitely TOWING. I upgraded our tow vehicle for just that reason. Quality vented/drilled rotors made a noticeable difference when trailering in the hills/mountains where you use your brakes a lot.
Very true. There you really see what heat does to the ability to brake
Yea but that's completely different and its exactly what he was explaining that bigger brakes are just larger heat sinks. Here you are not comparing stopping distance or power but the performance to reliably do that without fatigue. That's why you go for big brakes
You could consider an engine brake to prevent overheating your normal brakes (just like big trucks have) In hilly and mountainous terrain your engine is your primary brake source. Maybe a bit more difficult with an automatic tranmission.
Ive had brake fade down a steep hill, and its terrifying. Also a good reason to learn how to use gearing and engine braking. If you had to drop in to a lower gear to climb it, you need a lower gear to descend it on the other side.
@@str8xrippin It's actually directly related. Drilled and slotted rotors allow for gas venting and additional air flow to help with heat dissipation. Rather than adding more weight and brake equipment you can get better performance by going with better rotors. If you need a really serious brake upgrade for towing you probably want to examine your tow vehicle and probably go bigger. I was towing at max capacity for my Ford Freestar so the rotor upgrade was the most I needed, the next step would be getting a truck.
Haha, I'd hate to be one of the people who tried to call you out. So grateful to have someone who can share their in depth knowledge with the world :D
I love you man! Such a great teacher. Every video… I have the same reaction. I just delight and how you teach us the subject. Thank you man
I have to say, you are giving by far THE BEST explanations on mechanic and physic topics on youtube! So easy to understand with real word comparisons. Keep up the good work, you have a new fan and subscriber from Ljubljana. Svaka čast jarane!
Hard work you've gotten into trying to explain not so simple concepts to uneducated crowd... one of the best channels around for sure!!
That's literally what education is for. Problems start when some people are immune to knowledge.
I just swapped half defective, worn out shock absorbers with a brand new set. Now the new suspension forces the tires to stay more in contact with the terrain instead of leaving it to the springs to uncontrollably bounce around. I definitely think upgraded and if you are serious, adjustable suspension will give you more control for your money both in accelaration, cornering and braking.
I had a 1965 Impala with drums all round. Upgrading with discs up front and a dual circuit made a big difference.
I thought your last video was very well done. This one is superb.
Would be nice to have a video about brake bias depending on the weight distribution on the car
Too much braking force in the rear may cause locking of only rear wheels and loss of vehicle control (Oversteer.) Typical bias is front because of vehicle momentum shifting forward whilst braking.
almost all front engine cars are 70-30% the ABS module can vary this to zero rear and 100 front depending on many factors.
The issue about a video on brake bias is that it can never be objective.
@@vaerxxx3231 Yes there is weight transfer under braking but how much weight transfer is dependent on some vehicle physical attributes (such as the height of the CoG above the ground, weight distribution etc) but crucially weight transfer is also dependent on the rate of deceleration. Higher rate of decel will result in more weight transfer. And now it gets tricky because there are countless factors that can effect grip and thus peak deceleration (tyres, wet/dry road, weight etc). So in reality it is impossible for any passive brake system to achieve an optimum brake bias for all conditions. The result is vehicle manufacturers tend to opt for a 'safe' brake bias (i.e. forwards bias) because as you say, a overly rearwards bias would be like pulling up the handbrake every time you brake hard and that is definitely NOT the way to make a car fast.... However, since all manufacturers go for a very 'safe' brake balance, there is often performance to be found by shifting the brake bias marginally rearwards (e.g. by installing rear pads that have a slightly higher friction coefficient than the front pads). This will shift the brake bias rearwards towards a more 'neutral' brake balance which will reduce stopping distances. The tradeoff being the rear of the car will become slightly more unstable during braking.... A 5-10% shift REARWARDS in brake bias however is still very controllable for even a moderately skilled driver and could even further improve lap times by helping the car rotate on the brakes during corner entry.
@@adamfreeman3000 small corrections/notes factory brakes can also lock the rear wheels so no gain in stopping distance. Lap times might be improved as usually 'racers' like more oversteering behaviour. (Which is not really 'neutral' :) ) abs also does brake force distribution so it is not only hardware
Love this!!!! I've been telling people for years that just because you CAN do some mod or other, it doesn't mean you SHOULD! However, though you touched on it lightly, I think you need to consider that quite a lot of your audience (including, emphatically, myself) do NOT drive relatively modern cars with ABS and huge wheels that can accomodate huge discs. Some of us (NOT me, thankfully) may even be struggling with all drum brakes on 2 tons of 60s Americana with upwards of 400 BHP on tap (yes they really did sell such death traps!) My own case and that of many of my friends in the same boat (and the same car!) is similar, but not the same. We are cursed with a love of the 70s built Triumph Dolomite. It weighs around 1000kg, has 13" wheels and comes with a range of engines between a 58bhp 1300cc and a 127bhp 2000cc. But no matter what engine you have, you get the same 8.5" (216mm) solid front brake discs. Along with fixed, twin 48mm piston calipers. These are fine on the small engined models but totally inadequate for the HO cars, especially when tuned as well. The problem isn't necessarily size, per se, but as you said, it's heat dispersal (or lack of) and the fade that goes with it. The cure I and others have adopted is to retrofit the car with vented discs. These are slightly larger at 239mm (1" larger overall) and carry a 54mm single piston floating caliper, which are the biggest that can physically fit under the stock wheels, but the main point isn't the size but the heat dispersing capability of the vents Vs the original solid discs. The conversion is known well around the owners club and has no detractors. Over 150 kits have been sold which is pretty good when surviving cars number less than 1000 in ALL models. And whilst one person's experience is not, as you so rightly say, a statistical universe, 150 people are a step in the right direction! And we think that, in this case, with this particular type and model of car, that we DO actually know better than the OE manufacturer. The car stops a wee bit better, but more importantly, fade (which was always the biggest problem) has been completely eliminated, even under track conditions!
Thank you for this and all the other videos and lessons you summarised so well! This lesson was clear to me the first time you explained it, but it was necessary to repeat it for the ones who don't want to accept basic physics concepts. Btw. Besides learning with you, I really enjoy seeing Sarajevo sights in the background
Seriously good job on this. You managed to turn a contentious and quite hostile topic into something constructive and informative.
You are correct. Bigger brakes will not make you stop faster. The limiting factor is the traction your tires give you. It's pretty simple. However, at the track, you only need bigger brakes because small brakes will heat up faster and then become dangerous as they lose their braking power, and other things can happen too, like boiled fuild and such...
Not only will they be more reliable on track, they will also allow for less exhausting braking, due to the increased leverage and clamping force. But down the line every brake setup is capable of overcoming tyre traction.
This all was covered in the first video about this he made.
@@netts2315 Yes I know, yet people missed the point :(
@@netts2315 And yet, here we are, in a second video that had to explain the same thing again.
@@Phrew Well to be fair this video touched up more about stuff not presented in the original. My question was that wouldn't upgrading brakes matter once you upgrade the tires to have enough grip to not be able to lock up on stock brakes, and the answer is yes.
Thank you for putting this video out there for those car enthusiast who believe they know more than the engineers who designed them. Your video is well explained. Jason on Engineering explained has covered this as well. Thank you both for educating the community properly. Coming from an engineer in the automotive industry that specializes braking systems.
My only real scare on a public road with inadequate brakes was in an early 1960s car, small drums all round and an emergency stop from about 90mph. Massive fade and no servo made it scary. I did do a brake upgrade shortly afterwards as the car got treated to about 3 times the horsepower. (And might have to brake from significantly higher speeds). With more modern cars I have never felt a need for a brake upgrade, (for road use). The one scare with a modern(ish) car was on a track, the first few laps were fine but the fluid boiled in the front calipers after about 6 laps. This was after repeated massive deceleration from 150mph, something you would not do on the road. Well done on the video, absolutely accurate.
Fantastically clear and articulate explanations of these phenomena. It's a joy to watch a video that doesn't require figuring out the intended meaning in real time, even if that might be an excellent brain exercise, likely quite useful for fending off dementia! Thank yo so much for this fine work.
Some people live on a different earth with different physics I see, thanks for your 100% spot on explanation I really enjoy all your videos, I was binge watching your whole channel so looking forward to more content
I feel much better with the size of the brakes on my car. I’ve been worried about upgrading my car but not being able to spend thousands of dollars to get bigger brakes for it. Explaining high level science in a way the average jo bob in the garage can understand is a massive skill.
Yes please! hydraulic ratios, Brake bias, and proportioning (and metering) valve videos!
Man it made me so man every time a car reviewer slams the brakes on a nice car and goes "man these are nice brakes" then goes to talk about the brake rotor size. THANK YOU for helping put the right information out there even if some people are actively arguing with you.
yes! we want those videos about brake master cyls and brake balance plz!!
really appreciate the time you take to explain, and the respect that you afford to others in you response to criticism.
I think it makes sense that bigger/better brakes can stop your car more consistently after repeated stops. But outright brake distance will depend more on your tires. Very good analysis!
One thing that many miss is that massive, ultra powerful brakes also increase the unsprung mass of the car, possibly leading to worse suspension. (tyre+rim weight will, of course, have a bigger effect, but this is something many people don't think about) I was going to mention the brake feel aspect, but of course the video went into that! And yes please: videos on brake bias and all that other good stuff
Usually the stock single piston floating calipers on most vehicles are made of cast iron, while the fixed caliper multi-piston setups that most enthusiasts use for brake upgrades are made of aluminum, so usually brake upgrade mods get you unsprung mass weight savings. I have upgraded the brakes on my Mk7 GTI because it's my track car, and the stock floating calipers are perfect for street driving, but would overheat and fade after a couple of laps on a short track where the lack of long straights cannot cool them down between corners, especially when running on sticky track tires. The upgraded calipers (Audi TTS, fixed 4-piston aluminum calipers) even with the larger discs are about 40% lighter than the stock calipers & discs setup, plus the fixed calipers give a much better brake feel than floating calipers ever could, especially at the limit. Again, this is a track car setup, for street driving it would 100% be a waste, just like D4A says.
This.. I'm part of a car club for a specific vehicle model and in the early days of the club (early 00's) everyone was doing the "big brake upgrade" of pulling the bigger rotors and callipers from the sedan model and putting them onto the coupe model, but over the years it's become common knowledge that new oem coupe setups out-brake the sedan setups in every scenario, they were just made well enough that the heat dissipation advantages of the bigger rotors and callipers were completely negligible compared to the disadvantages of the unsprung mass increase even in track situations. So the only way to get better brake performance is to splash out on track specific systems that are lighter, which are few and far between for 25 year old Mitsubishis.. This really clicked for me when I went from 6.5" alloy to 8" steel wheels as a teenager.. I figured wider = wider tyres = more grip = better performance but in reality on a car that weighs less than 900kg (1900ish lbs) the 8" wheels were *that* much heavier that there was basically 0 performance increase. Currently sitting on a much lighter set of 8" alloys and the difference is crazy. Now the limiting factor is that the stock seats dont hold me straight enough to corner any harder lmao
Not only would larger breaks negatively effect the sprung/unsprung ratio, giving worse teaction, & actually negatively effecting breaking distance.. and everything else your suspension does, then there's also the spinning mass consideration. Anything spinning on a car has to be accelerated twice. Once to turn it, & again to move it forward. Twice as much energy is expended in moving a spinning part. Meaning that 1lbs of weight reduction on a spinning part is worth 2 lbs anywhere else on the car. Between that & the unsprung ratio, this is why lighter wheels is such an important modification in sports applications. This is true, of course, not only for accelerating the part, but also for decelerating it. More force is required to stop a spinning part than a fixed one.
Unsprung, ROTATIONAL mass. Which is the worst kind of weight on a vehicle.
@@mr.e8282 It's even worse than that! The angular moment of inertia for the brake rotors will increase with the square of diameter, i.e. doubling the diameter will quadruple the momentum needed to spin it to the same RPM. So a rotating part takes 2 times the energy to move as a non-rotating part, TIMES the square of the diameter!
Good explanation on clearing things up. I think a lot of people were thinking about the theoretical model of just increasing braking force instead of the application of bringing an actual vehicle to a stop faster.
You are absolutely right. My truck is over weighted comparing to stock, and I use mud tyres. Break distance has increased considerably and I was thinking on updating the break system. I had to run without abs and surprise: stock calipers has enough force to lock the tires immediately, regardless the extra weight, speed, etc.
I would absolutely LOVE a video on piston ratios and brake bias etc. I have yet to find a great video like you create on this subject!! Hook it up!! Thank you in advance!!
You are very good: 1) easy to listen to; 2) enthusiastic; 3) clear presentation of written and visual aids; 4) organized; and 5) 100 % factually correct. Thank you
Loved the video. What most people probably experience is that their new brakes bite harder after "upgrading", which hopefully feels nice, but does nothing to reduce braking distance at the tire limit. I also wanted to add that even for track day use, all you need is brake pads and fluid designed for track use. Because they work at higher temperatures, and maintain brake force even after repeated stops. Brake caliper and rotor upgrades may look nice, but sometimes actually alter the brake bias front to rear. This may or may not be beneficial depending on what tires you use, and how you prefer to drive into corners. And BTW, upgrading brake calipers and rotors and then still mounting street-type brake pads gets you nowhere for track use. It is really the pads, fluid and cooling that makes a big difference, not calipers and rotors. Unfortunately most brake pads designed for track use do not work well on the street, so you end up having to swap back and forth. Carbon ceramic brakes may be an exception to this.
Carbon ceramics are bad for track use, they fail quickly when exposed to excessive heat. But they're perfect for street driving, no brake dust and last forever
you hit on something there. a more intense bite is a negative on breaking performance, as it reduces ability to modulate the brakes. those who find that increased bite to be an advantage likely are terrible at using brakes in any performance situation
@@stevesamuel263 Don't forget they are ridiculously expensive. No one is tracking carbon ceramic rotors without having a trust fund or rich sponsor. Replacements are thousands of dollars.
if you have a japanese car dixcel makes some really good pads rated for both street and track use, but they are definitely not cheap even when not including shipping. dixcel z-type pads, bought them for my car after i had a bit of brake fade after some fairly hard mountain runs. these things can brake all day, but they do emit a lot of dust.
New breaks decrease braking distance. You start going into nuances which author of the video did not went. He talked about ABS, but omitted to tell you how ABS INCREASE braking distance. That is only natural, because they keep on releasing brakes during braking. And why you are concerned about emergency braking distance? Better brakes will no doubt decrease distance it takes to brake due to tire lockout, but it will come at a severe trade off of braking control. Either way, a skillful driver can replace ABS by just being good by simply disengaging brakes himself when he need to shift directions.
You’re a gift. Please continue doing what you do.
Right, your description of brakes as a heat sink is a really good way to put it! If your car can lock up all 4 tires with stock brakes then upgrading your brakes isnt going to decrease your stopping distance, the tire friction is the limiting factor. Somebody may subjectively think that upgrading their brakes made the car stop faster because it decreased how hard they have to push the pedal to lock up or stop fast, but the overall braking distance will be the same (or even longer for an unskilled driver who is now locking up the tires immediately). That said, if you are driving your vehicle at high speeds on a regular basis you may want that larger surface area to keep cool and reduce brake fade. Here in america it is more and more common for traffic flow to go 90+ mph on the highway. Still technically illegal but you see it all the time and it barely gets enforced. So remember, kinetic energy increases with the square of velocity meaning if you go twice as fast your brakes have to shed 4x as much energy to stop you. I would argue that most stock brakes will experience some degree of brake fade during a single emergency stop from 90 mph. Especially something like a massive 6000 pound american SUV with 300+ hp that feels totally tame at 90 mph but still uses fairly standard brakes. Brake fade is no joke and it can sneak up on you faster than youd think
A major point you missed here is that upgraded brakes look cool, hence, better stopping distances.😉 Good job, D4A. Looking forward to your next video.❤
Plus how much better it runs and handles.........after a wash 😁
Adds more horsepower than a turbo.
Red ones stop better.
Don't forget, every JDM sticker added to the rear window is an extra +25hp
🤣
Nowadays I just service my motorbikes by myself, yet I am still a petrol head. Your channel is definitely one of the best in taking time and delving very 'rationally' into the details. Learning or refreshing knowledge. Thanks for your great work!
I expected something totally different from the postings title. I was smiling as this video progressed, well done! Lbs. Per Square inch, tire and road friction capabilities are far understated in a proper aftermarket brake system change. It is physics and the posters arguments are solely with physics and not you. Very well done video.👍
I'm working in brake development at TMD-Friction (there were even a few clips of one of our test vehicle in your video). Every time some car forums go wild about brake theories I have to bite my tongue to hold my shit together 🤣 I feel this misery deeply, trust me. Much appreciated 👌🏻👌🏻👌🏻
Id love a detailed vid on Brake Bias, Master Cylinders etc. Keep on going
I agree with what you are saying. Once i increased the power of my stock engine to nearly double, on day to day driving around town i did not need a big brake updated. However once i started driving on track, i found out that after the 3/4th lap my stock brakes gave up and. my next investment was bigger brakes and disks which helped on track, but yet again on day to day driving i cannot see i massive increase in stopping in town with the bigger brakes.
I'm amazed that people disagreed with this. I've had various old cars with over the years and none lacked brake force (although some required a lot more pedal force to lock up the wheels). Example, a 1956 Morris Minor with tiny 6" drums all around and no brake booster... They were regarded as very average brakes even in their day, but you could lock up all 4 wheels no problem even with modern tires. The problem with the small drum brakes was overheating due to poor heat dissipation, and also uneven lockup and poor control in panic braking situations, not lack of brake force.
You are absolutely right about this, your brakes don't stop your car, they stop your wheels from spinning. What stops the car is the friction between the wheels and the road, and the maximum friction you will get to the road is when you are using barely not enough force to lock up the wheels. Once the wheels lock up, they start to slip, and friction is drastically reduced, so once your brakes are strong enough to lock up your wheels, making them stronger will not increase the friction to the road, and hence will not improve stopping distance. Just a nitpick however, Gs are a measure of acceleration, not force. One G means 9,81m/s^2, which means you accelerate/decelerate at the same rate as gravity.
I came across youyr channel a few weeks ago and i have to say, it is just what i need. Someone who obviously knows what he is talking about and presents it logically. we really need more people who think like this, look at the world and dont feel, but try and contrast. I love it, keep it up. It makes me really think. I love it. I love you, and its amaizing. Thanks Im a fan!!
Good video. Another thing to consider is that bigger brakes will often increase unsprung weight. And that has a negative impact on handling. Because of that, I would only use bigger brakes if absolutely necessary.
This is true and it often times is offset by much lighter aftermarket wheels. The overall weight though may still increase depending on the size of said wheel tire combo.
Very good point!
@@spartancrown I'll take adequate, lighter brakes *and* lighter wheels FTW.
I do not know how to call it proffesionally because English is not my 1st language, but the good thing you can do is to change your rotors to the ventilated ones of the same size as you had before. They will overheat less easily and weigh the same.
@@johngalt97 Agree, just look at the F1 in 2021 or 2020 vs now. Bigger wheels are slower.
This is very interesting, and makes a lot of sense.... I'm probably a slight exception in that my project car is almost 50 years old, and came with pretty horrible brakes. However, the first upgrade to the brakes I did was to swap 1985 small truck disks onto my 1975 compact car. This worked very well, but in the interest of reducing weight, I eventually swapped the stock truck brakes for a light weight "big brake" kit. This did reduce weight significantly, but didn't seem to change braking all that much. However, the only time I've lost control on the track (1/4 mile drag strip) was when running skinny front tires and hitting the brakes hard (trying not to break out while bracket racing). Thankfully I recovered before crashing, but it was indeed the front tires and not the brakes that limited my braking ability in that case. Brakes as a heatsink is a good thing to remember.
I'm glad you made videos on this topic. I wrote an article as part of a college physics project about static vs. dynamic friction covering the same topic, arguing that bigger brakes are only good for dissipating more heat and better tires would be the best solution to cheaply reduce the stopping distance of your average car. The professor wasn't really a car guy, but he was impressed nonetheless since he had never really thought about it in depth, never having needed to do so, and just assumed that better brakes would be the first thing to improve.
@@ss-mw9dj It's a marginal improvement at best. Did you not even watch the video?
@@ss-mw9dj No, you are confused. The automakers put those high end brake systems on their cars for all of the other benefits of big brakes. You can take your 911 GT3 RS straight off the showroom floor and flog it on the racetrack all day with no signs of brake fade. But you're not going to do that with your Chevy Cavalier. But either one of those cars can do a mighty fine panic stop and lock up the brakes, although the GT3 RS will be much less likely to lock up the brakes not because of the brakes themselves but because the tires are so much more grippy. You need to look at the entire car as a system instead of saying "bigger brakes stop more good!"
@@ss-mw9dj "You're saying that if you can lock up your tires then your stopping distance is capped" Yes, that's what I'm saying. That's what driving 4 answers is saying, too. Locking up your tires means you exceeded the static friction coefficient of your tires. That is the maximum limit of grip of your tires. Grippier tires have a higher static friction coefficient, therefore they help you brake harder. Once you exceed that static friction coefficient by locking up the wheels, you will either start sliding (sliding coefficient of friction is lower than static coefficient) and/or ABS kicks in to help you brake more effectively by unlocking the wheels to get you back to the static coefficient of friction again. A highly experienced driver can figure out the limit of grip, i.e. staying just below the static coefficient of friction without exceeding it, therefore getting the maximum braking power without sliding or activating ABS. It's called "threshold braking." Again, you are missing out on the whole picture concept here. That 911 GT3 can outbrake a Chevy for many reasons. The chassis/suspension geometry is one factor. The grip of the tires is another factor. The brake *balance* is yet another factor. Aerodynamic braking is yet another factor. And if you put some super grippy tires on any Chevy, it's likely to be able to do a single panic stop in almost the same distance as the Porsche, mainly because the brakes themselves really aren't the main factor. Big brakes are designed to convert the kinetic energy of a car into heat energy and dissipate it to the environment, and better brakes are just more efficient at the dissipation part. I mean, seriously, you're acting as though you didn't even watch the video that you're commenting on. driving 4 answers gives a great example starting at 8:00 of a McLaren Senna vs Mazda MX-5 vs Toyota Aygo, and their braking distances from 100km/h to a stop are very, very close despite the Senna having a braking system that probably costs more than the other two cars combined. driving 4 answers covers all of the pertinent info in this follow-up video and in the original video, so why don't you go watch them both a few times until it sinks in?
@@ss-mw9dj Modulating throttle has nothing to do with braking, so I have no idea what you're going on about. I didn't say a "1cm wide brake can stop a car better than a 30 cm wide rotor." driving 4 answers said that typical braking systems on normal cars are absolutely sufficient for bringing the car to its maximum braking abilities i.e. exceeding the maximum friction of the tire and locking up the wheels, and I agree with him on that point. You need to take a few physics classes, specifically in a topic called "statics," which will give you all the information you need. I'm sorry that you're uneducated on the topic, so just go ahead and stop arguing.
@@ss-mw9dj "modulate throttle" You must mean modulate brake pressure? Throttle is a valve that allows air into the engine to make the car accelerate. Again, the throttle has nothing to do with braking, unless you're using engine braking, but that's way, way less powerful than what even the most basic, crappy brakes are capable of, and really irrelevant in this discussion. And I absolutely agree with you if you're running your car on the track at all: bigger brakes would benefit you greatly since you'll get much better feedback through the brake pedal, much better fade resistance, etc.! But for normal street cars, upgrading your brakes is just a waste of money! The "brakes are everything" crowd are just cringe and think that you can't attribute anything to anything other than brakes. Btw, this opinion only exists on Reddit or places where people don't actually track their cars. Go figure.
I seriously can not thank you enough for how much you have helped me with understanding cars over the years. You alongside with Engineering Explained have incredibly informative videos, that are short, brief and straight to the point, I'll be it with some skits here and there but that's always fine :). If you were to read this, I would recommend doing some videos on race/street suspension, how it works and how it could be improved. Also, maybe more videos on rotary engine dynamics? Could be both interesting choices, just a recommendation though! Have a great day/night!
he's store brand jason from EE. great guys, both of them!
This is so true d4a and ee ate the best
EE is incorrect so often that I unsubbed. He uses "math" to 'prove' incorrect positions. Take the hydrogen fuel video from a while ago. "Oh, the fuel tank volume of a GTR gives the car 50mi range" GREAT its designed for a DIFFRENT FUEL. No shit its not optimized for hydrogen, its designed for gasoline. The hell does that prove? Li-ion is 0.08kwh/L and hydrogen is 1.1kwh/L(@500bar, not unheard of. Can go up to 2.3kwh/L) So all battery cars are invalid? He argues that hydrogen cars are mathematically impossible, and while BEVs are less than hydrogen. What a shill and a clown.
@@thenewhalogod Glad i'm not alone. Guy annoys the fuck out of me.
And Unlike EE, this guy doesn't have the voice of Kermit The Frog, which makes his points much easier to follow.
It makes perfect sense. I'd like to see a video where you teach us how tire width changes the braking distances and how they affect cornering.
I would add "and a grip on the snow etc"
we definitely need a video on tyre width and it`s effects on grip, especially. There seem to be many missconceptions floating around.
I put urethane control arm bushings on my 1998 Camry, upgraded the steel 14-inch wheels to 16-inch Lexus ES330 wheels, and put wider, lower profile tires on the car. The tire size was carefully calculated to maintain the same outer diameter and circumference to about half a percent, IIRC. With that, I also kept the stock front brake calipers and rotor diameter, but upgraded to drilled & slotted discs sandwiched between ceramic brake pads. Later I ditched the rear drum brakes (5S-FE 4-cylinder) and installed the rear disc brakes from a V6 Camry of the same model year. Acceleration with that 130 HP 4-banger was "meh", but the car cornered and stopped quite well (even with a loaded trailer).
Being a biker, too much tyre width on the front just screws up the steering. Which leads me to also favouring a softer compound for the front tyre.
i think people forget that if u can lock up ur wheels with stock brakes, you wont be able to stop faster with big brakes.
Best video yet! Personally, all I've ever done is steel braided lines for pedal feel and knowing they're new, nice sticky tyres (I'm partial to Nitto Invos), and Carbotech XP8 pads with a friction coefficient of ~0.58-0.60, you're avg brake pad typically have a friction coefficient of ~0.3-0.4. With that setup you'll need to relearn all your braking points and thresholds otherwise you'll be stopping way farther away then you expect! 😆
Brakes get me super emotional !!😂
I absolutely need more of this on brake ratios, master cylinders, and everything you know about it
Thank you! I've always said this and got the same responses as you. I'm bookmarking this link as my future response.
The TL;DR is that if your brakes are capable of locking up with the tires you're using, they have more than enough force. You can't stop faster without increasing grip. Big brakes are primarily for fighting brake fade from overheating due to heavy, repeated use. There's one sort-of-exception: if you switch a car on stock brakes to racing tires, the stock brakes might no longer be enough to lock up with the increased grip, meaning you do need more force from the brakes themselves.