What would be the point of bigger rotors...

[spidey07]

Originally posted by: randay
Um, your car will come with brakes strong enough to stop your car... otherwise why would it come with brakes at all?

Ever press down on the pedal and not be able to stop???

That's why you have bigger rotors.

 

[91TTZ]

Originally posted by: spidey07

Originally posted by: randay
Um, your car will come with brakes strong enough to stop your car... otherwise why would it come with brakes at all?

Ever press down on the pedal and not be able to stop???

That's why you have bigger rotors.

No.

Even the aforementioned Civic has enough braking power to skid.

Please list one car that has brakes too weak to make it skid (or activate ABS).

After repeated braking, they'll fade, though. But that's not what happens in an emergency situation.

 

[Viperoni]

A lot of brake fade has to do with brake pad selection.... the average $30 set of pads are worthless for anything more than a two hard stops in a row.

For hard racing use, yes bigger brakes will be better.

 

[BrownTown]

my rotor is bigger than yours! So is my stator.

 

[nineball9]

Heat dissipation. A friction brake works by translating kinetic energy to heat.

Friction is not a function of contact area for dynamic (kinetic) friction. Wikipedia

 

[I Saw OJ]

I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

 

[91TTZ]

Originally posted by: I Saw OJ
I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

That's because the show is sponsored by these companies. You can also find reviews that "prove" that the tornado, and other bogus mods work.

It most definitely will not shorten the 60-0 stopping distance, since that is a limitation of the tires. If you jam on the brakes with even stock rotors and pads, the tires will skid.

 

[I Saw OJ]

Originally posted by: 91TTZ

Originally posted by: I Saw OJ
I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

That's because the show is sponsored by these companies. You can also find reviews that "prove" that the tornado, and other bogus mods work.

It most definitely will not shorten the 60-0 stopping distance, since that is a limitation of the tires. If you jam on the brakes with even stock rotors and pads, the tires will skid.

I can jam the brakes in my Cobra, which has stock brakes, pads and tires and the tires do not skid.

BTW are you compairing the tornado to Brembo brakes?

 

[nineball9]

Originally posted by: I Saw OJ
I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

The custom brake pads/rotors may have had a higher coefficient of friction, or perhaps better heat dissipation, or possibly flatter surfaces than stock (to maintain constant surface contact). Maybe just better mechanical design; rotors, pads, calipers etc come in many designs.

Or perhaps, as 91TTZ noted, it's just that the show is sponsored by these companies. (Sorry, I know zilch about "Brembos")

 

[thedarkwolf]

Originally posted by: I Saw OJ

Originally posted by: 91TTZ

Originally posted by: I Saw OJ
I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

That's because the show is sponsored by these companies. You can also find reviews that "prove" that the tornado, and other bogus mods work.

It most definitely will not shorten the 60-0 stopping distance, since that is a limitation of the tires. If you jam on the brakes with even stock rotors and pads, the tires will skid.

I can jam the brakes in my Cobra, which has stock brakes, pads and tires and the tires do not skid.

BTW are you compairing the tornado to Brembo brakes?

Probably because you have ABS

 

[91TTZ]

Originally posted by: nineball9

Originally posted by: I Saw OJ
I watched a Hotrod TV episode a while back where they replaced a Camaros stock disc brakes with a nice set of larger Brembos. With just a disc and pad swap it greatly reduced the 100-0 and 60-0 stopping distance of the camaro.

The custom brake pads/rotors may have had a higher coefficient of friction, or perhaps better heat dissipation, or possibly flatter surfaces than stock (to maintain constant surface contact). Maybe just better mechanical design; rotors, pads, calipers etc come in many designs.

Or perhaps, as 91TTZ noted, it's just that the show is sponsored by these companies. (Sorry, I know zilch about "Brembos")

Since the tire ultimately has to hold the car to the road, if the stock brakes can make the tires skid, then stronger brakes will also make them skid.. the tire has nothing more to give.

It'll help with fade, but if you encounter fade on the street, you're either doing something wrong or illegal.

 

[91TTZ]

Originally posted by: I Saw OJ


I can jam the brakes in my Cobra, which has stock brakes, pads and tires and the tires do not skid.

BTW are you compairing the tornado to Brembo brakes?

Your tires will skid. The ABS system just is able to detect it and compensate so quickly that you don't notice it.

And I'm comparing the review of one product to the review of another, as far as magazine objectivity goes. When that company is helping the magazine pay its bills, it doesn't matter whether the product is legit (brembo) or not (tornado). They're going to get good reviews as long as they're paying.

Remember, Slick 50 used to get a lot of good press also.

 

[Thorny]

Anyone who says there are no benefits to larger rotors (or better made) is just plain wrong. Better control and resistance to fade are MAJOR benifits if you have a performance vehicle. There are several reasons you could benefit from them, such as towing heavy loads, living in mountain terrain where you can suffer from fade or having oversized tires and wheels. For those of you that say that stock brakes are sufficient, perhaps that is true for your car, but not for all. Stock brakes are matched to the car, and any modifications (such as improving traction with wider tires, or increasing rolling weight with mud tires )to the car can suddenly make your stock brakes insufficient.

My stock Nissan truck cannot lock the tires to skid, and the ABS has never kicked in on dry or wet pavement. My Z28 however will lock all four with precision, thanks to its huge rotors, even though it's got twice the traction of my truck.


Edit for clarification

 

[Minerva]

Increase in swept area as long as pad type and size match the increase. In the days of discs in front and drums in rear the drums always had more swept area but drums will fade faster. I had a 73 challenger with drums all the way around and the drums had fins on them. I was never a fan of ABS as I grew up on conventional brakes. If you're used to that and you brake with ABS by pumping/modulating the pedal it can cause a hazardous condition. Fortunately we rarely see the slick stuff here.

(but that never rules out the parking lot donuts!)

 

[loic2003]

Since brakes convert kinetic energy into heat, perhaps a larger 'rotor' (it's disk, you fiends!) would dissipate heat more effectively, thus allowing it to perform within optimal temperature ranges for longer periods of time?

PS Stop posting.

 

[TankGuys]

Surface area won't increase the friction at all. The only way to increase the friction is to use material on the rotor/pads with a higher coefficient of friction, or to increase the force with which the calipers squeeze. To the surprise of many, surface area does not matter

 

[spidey07]

Originally posted by: 91TTZ
No.

Even the aforementioned Civic has enough braking power to skid.

Please list one car that has brakes too weak to make it skid (or activate ABS).

After repeated braking, they'll fade, though. But that's not what happens in an emergency situation.

I was talking about when you're tearing up the twisties and your brakes turn to mush.

 

[Jahee]

Originally posted by: TankGuys
Surface area won't increase the friction at all. The only way to increase the friction is to use material on the rotor/pads with a higher coefficient of friction, or to increase the force with which the calipers squeeze. To the surprise of many, surface area does not matter

I find that hard to believe, very, take a rotor with a CM of useable braking surface, then take one with 10, i find it hard to believe they will stop the car in the same distance if identical force is used on the entire braking surfaces

 

[AdamK47]

Smoke em until the tires start dripping.

 

[Zenmervolt]

Larger rotors allow for several things. Foremost is leverage. Because the pads are effectively further from the rotational center, they are able to apply greater leverage against the wheels when braking. Larger rotors also allow larger calipers to be used, which in turn have larger pads. The large pads distribute the braking force over a greater area and, when coupled with multi-piston calipers, allow better control over the pad surface which decreases the likelihood of lock. As has also been pointed out, larger rotors have more area from which to dissipate heat.

ZV

 

[MercenaryForHire]

Originally posted by: spidey07

Originally posted by: 91TTZ
No.

Even the aforementioned Civic has enough braking power to skid.

Please list one car that has brakes too weak to make it skid (or activate ABS).

After repeated braking, they'll fade, though. But that's not what happens in an emergency situation.

I was talking about when you're tearing up the twisties and your brakes turn to mush.

Sinking Feeling
noun - sink-ing feel-ing
def: The disconcerting sensation of putting your foot on the brake and touching the floorboard.



- M4H

 

[Fern]

Originally posted by: randay

Originally posted by: Jahee

Originally posted by: 91TTZ

Originally posted by: Jahee

Originally posted by: giantpinkbunnyhead
My guess would be that larger rotors provide more surface area for heat dissipation, thus keeping brakes cooler and reducing fade. Plus, if you're going to bigger rotors, you'll probably have bigger calipers and pads as well.

You forgot the big one... Bigger surface area for friction!!

That's not really a bottleneck, though. Even stock brakes produce enough friction to make the tires skid.

Thats true... Though in high performance cars (which are most likely to have bigger rotors), the width of the tire increases aswell, as, generally will the weight, meaning "average" brakes won't generate enough force to lock the wheel.

Um, your car will come with brakes strong enough to stop your car... otherwise why would it come with brakes at all?

I assume this question is inspired by the Toyato Tundra commercials.

Hence I suspect that this has to do with increased payload capacity etc.

Fern

 

[eleison]

good point.. bigger pads only help with heat dissipation... didn't really think about this until now..

 

[andylawcc]

Originally posted by: slag
bigger rotors=more friction area for braking. Also bigger rotors dissapate heat better due to larger surface area.

the friction area is also depended on the brake pad size too

 

[andylawcc]

Originally posted by: Jahee
Thats not my point. Take, for example a BMW M3, with 500-700 extra pounds of weight + wider tires. over a small hatchback, for example a civic, will the civics brakes generate enough force to lock a wheel? im guessing not likely.

i can easily lock my wheel on my celica (which is roughly the same weight as a similar gen civic at 2500lb) at any speed. Just floor it hard enough.