A lot of us actually tend to relate bigger brake size with better braking distance, and if you have a keen enough eye, you must have surely looked at the enormous size of the brakes offered on some high performance cars and possibly even thought that ''why not upgrade our stock brake setup to bigger brakes the next time, so that we can stop quicker?'' At the end of the day, size matters right?? Well, stick around till the end because we have something quite interesting to tell you about it.
Common Misconception
Bigger Brakes, as in, increasing the size of your brake discs, brake calipers or even your brake pads Do Not Reduce Your Braking Distance. This is contrary to our intuition because we tend to assume that bigger brakes provide increased surface area which means more frictional force being generated, translating into stronger braking force and hence a shorter braking distance. But if we talk physics, it decides to rather disagree with our assumption and instead says that no matter the difference in surface area or the sizes of the two surfaces under consideration, the frictional force remains the same, because the weight of the object remains the same and the frictional coefficient remains unchanged.
From a microscopic POV, one may find that objects are neither perfectly smooth nor evenly rough over their entire surface, and this is why surface area often matters in real life situations. But modern day brake pads and brake discs being machined very accurately, are pretty uniform over their entire surface, and hence increased surface area of brake discs and pads DOES NOT LEAD TO INCREASED FRICTION. Even if we were to factor in the increased leverage from a larger brake disc, first of all you cannot gain a significant amount of additional leverage because there is a physical constraint as to how much you can upsize your rotors, and the gains are anyways quite low and hence it doesn't change things much.
Bigger v/s Smaller Brakes
If you compare two identical cars, one with stock brakes and the other with upgraded 'bigger' brakes and drive them to their limits, they would brake equally well for the first few minutes. Only after several minutes of spirited driving and extensive braking cycles will the stock system start to overheat, causing the brakes to significantly fade and its braking performance to be dramatically reduced, while the upgraded braking system might retain the same braking performance with the same consistency for a much longer period of time. When you trying to stop your car with the brakes, what you are basically doing is converting kinetic energy into heat, and then the main function of the brakes dissipate that heat into the surrounding air. It's as simple as this: If you can't overheat your stock brakes, then you don't really need to upgrade them under normal driving conditions.
Do you really even need a Braking Upgrade?
A brake upgrade might be necessary if you make a remarkable increase in the weight of your car, because it is much easier to heat up your brakes in this case. Another scenario where you should probably upgrade your brake size is when you have significantly increased the power output of you car, so that the upgraded brakes would help to be able to hold up more consistently from slowing down your car from those higher speeds and acceleration levels which your stock brakes were probably not designed for.
Increasing the braking force further a certain point anyways cannot reduce your braking distance, and that is because your tires are the only point of contact between the your car and the road surface. Having more powerful brakes on a car with poor or even average tires makes 'ZERO DIFFERENCE', as the tires will not be generating enough traction to keep your wheels rolling upon heavy braking, hence causing your tires to simply skid and thereby causing the ABS to kick-in even quicker than before. Every single new, or fairly new car on the market in today's times has more than enough braking force to be able to lock-up the wheels, and this is why we have ABS as standard on all cars.
Braking Distances Compared- McLaren Senna v/s Maruti Swift:
How about an interesting comparison to put our claims to test? Let's take an example of two wildly different cars intended for two completely different uses and see how they are against each other. The first one is the McLaren Senna, an absolutely stunning 800 horsepower million dollar track focused hypercar, with a state of the art carbon ceramic brakes, and our second car is the rather very humble Maruti Suzuki Swift. Given below, is an illustration comparing how well these cars score compared to each other on a braking performance test (in ideal conditions with approximated figures).
As you can already make out from the comparison, despite the astonishing difference in the make and size of the braking systems, there is NOT A NIGHT AND DAY DIFFERENCE when it comes to their braking distances. The reason for this is that the modern braking technology has already reached it's sensible limits, allowing the vehicle to be safely slowed down without subjecting it's driver and occupants to excessive amounts of G-forces, and this is why the average braking distances across any car categories don't dramatically differ from each other. The sole reason why hyper cars have giant brakes is because they need those to maximize the 'surface area' for it being able to repeatedly dissipate the ridiculous amounts of heat that is generated when braking from the kinds of speeds that hyper cars are capable of achieving, THAT'S IT! Infact, most of the race cars like the McLaren Senna have drilled brake rotors, showing that manufacturers are willing to sacrifice surface area for heat dissipation, and that pretty much reverberates what we have already just explained to you.
Here's What will 'Actually' Reduce your Braking Distance
Given the fact that most of the cars are coming with either undersized or sub-par quality tires from the factory under the pretext of 'cost cutting', especially in the budget cars, the stock braking systems can suffice to almost all of the regular car users and upgrading to a set of better tires having better composition and tread patterns, and of the correct propositions according to your vehicle might actually be a more sensible and easy option. Wider and better tires will not only add to the aesthetics of your car, but will also offer more grip and better traction, but also somewhat improve the dynamics of your vehicle, they also give better and more consistent performance, all while 'actually' helping to reduce your braking distance.
Wrap-Up
We hope that we were able to clear off some of the misconceptions around this topic. You can browse through our website for more of such insightful blogs and honest ownership reviews. You might also be interested to checkout some genuine listings for used cars or you might opt for a paid car consultancy from Mr. Munish ji for any car related expert advice. Do consider subscribing to our YouTube channel and Thanks for stopping by!