Tracking the stock callipers

[stuntman]

I will send pics of the brembo rotor later. They were small cracks originating from the holes, which didn't bother me, except some of them extended to and up over the edge of the rotor. Over the edge was the deal breaker.

I agree both the pfc01 and the dtc are very streetable. Yes they dust, but it is a very fine dust. And it seems to me that any squealing originates from pads on the rear caliper.

And I remember your photos of the destroyed rb rotor. The more disturbing part was their lack of customer service. I've had good luck with their 1pc on the rear and their replacement rings for the brembo hats for the front. Billy $1200 for a pair Brembo rings is a rape job.

sent from my Evo4

Don't get into motorsports then. Also, the Brembo slotted rotors will last a very long time. Please do post the pics of the drilled rotors.

I streeted my DTCs (lazy) and they were OK. The bite left much to be desired when the weather was cold and you were starting out on a drive or had been cruising (not using the brakes for a while). The squeak got old and eventually they started to really make aweful noises when breaking hard at speed (despite enough pad material left they seemed past there lifetime...and looked a little crumbly when I took them off). I thought my rotors were trashed...but all was good again with new pads. If I go back to DTCs for the track I will swap with something more-reasonable for the street. I wonder (pure speculation - a hypothesis) if the deposits degrade over time given street driving and that with the one-lap you didn't have bite issues because you didn't go long. I have no complaints about rotor wear.

I just finished the One Lap of America and put over 4,500 street miles on DTC70s on a Roush Stage 3 Mustang. The Cold bite (40*) was very agressive, touchy, and hard to modulate. It required very little pedal pressure to almost engage abs. they were also harder to modulate IMO on track.

They do squeal but a lot of exotics (Ferrari F40, 430, Carrera GT, GT3 RS) and many performance cars especially those with ceramic brakes squeal. I find it cool but others are really irritated by it.

Still be cautious mixing pad compounds, significant shudder is a common byproduct.


0.02

 

[CL65 Captain]

Please do post the pics of the drilled rotors.

This was after two weekends (4 track days + ~ 1000 street miles to and from the track). Putnam and Autobahn CC. Running PFC01 pads. I pulled them because of the cracks that went to the edge and over the top of the edge made me nervous. Both rotors had about 3 to 4 cracks that went to/over the top edge.

Also, the Brembo slotted rotors will last a very long time.
0.02

At $1200 vs $400 for rings they would have to last 3x as long.

 

[e.pie]

Drilled rotors are pretty much universally bad news.

 

[Chris_B]

Drilled rotors are pretty much universally bad news.

For serious track work (other than qualifying), you are correct. Otherwise, this is a seriously under-informed comment.

Chris

 

[e.pie]

For serious track work (other than qualifying), you are correct. Otherwise, this is a seriously under-informed comment.

Chris

Unless you never use them, 99.9% of the time they will crack prematurely vs. a blank or slotted rotor.

 

[Chris_B]

Unless you never use them, 99.9% of the time they will crack prematurely vs. a blank or slotted rotor.

That is the quick, Internet myth reply. The reality is that properly drilled rotors (using quality blanks and good machining and finishing practices) are just fine for the street and light track or autocross use, which is why you find them as OE on many vehicles. Think: Porsche, Mercedes-Benz, BMW, Lotus, McLaren, Corvette Z06, etc. Except in cases of extreme abuse, they most often wear out before they crack.

It's when someone goes balls-out that it is time to move to J-Hook or slotted rotors. And, yes, I've had decades of experience with all types from mild street vehicles to IMSA and NASCAR teams. Of course, if one were to buy the cheap crap off of eBay, all bets are off. Let the buyer beware.

Chris

 

[stuntman]

Drilled rotors with 90* edges are stress risers. -Lead to cracking.

Tri-Point used Brembo's "Street" drilled rotors, i'll have to call my buddies over there to see why, but almost all motorsports applications use a type of slotted rotor.

OEM drilled street rotors (porsche, ferrari, mercedes, etc...) IMO do not justify the performance of drilled rotors. IMO they are more of a marketing 'bling' than performance enhancing.

 

[Chris_B]

Drilled rotors with 90* edges are stress risers. -Lead to cracking.

Tri-Point used Brembo's "Street" drilled rotors, i'll have to call my buddies over there to see why, but almost all motorsports applications use a type of slotted rotor.

OEM drilled street rotors (porsche, ferrari, mercedes, etc...) IMO do not justify the performance of drilled rotors. IMO they are more of a marketing 'bling' than performance enhancing.

Properly drilled rotors do not have 90° edges. They are radius chamfered with a corner rounding tool. Those that aren't need to be peened with a ball bearing to put compressive stresses into the hole area.

Again, my comments about drilled rotors exclude motorsport use -- except for qualifying, where they have been used with success.

It has been proven in labs and on test vehicles (I've done some of that testing) that drilled rotors provide more initial pad bite than smooth rotors. They are slightly better than slotted rotors, depending on the slot pattern chosen. The great thing about J-Hook rotors is that they have practically the same bite as drilled, but none of the stress risers, which is why you see most professional teams using them. If people like the looks, then fine. But they do work!

Chris

 

[stuntman]

Properly drilled rotors do not have 90° edges. They are radius chamfered with a corner rounding tool. Those that aren't need to be peened with a ball bearing to put compressive stresses into the hole area.

Again, my comments about drilled rotors exclude motorsport use -- except for qualifying, where they have been used with success.

It has been proven in labs and on test vehicles (I've done some of that testing) that drilled rotors provide more initial pad bite than smooth rotors. They are slightly better than slotted rotors, depending on the slot pattern chosen. The great thing about J-Hook rotors is that they have practically the same bite as drilled, but none of the stress risers, which is why you see most professional teams using them. If people like the looks, then fine. But they do work!

Chris

Which drilled rotors are you referring to?

Regardless, for those buying replacement rotors, just go with slotted.

I know you're an AP dealer and continue to rave about the J-Hook slot design but show me data where they have 'practically the same bite as cross drilled and more than slotted'. You're talking micro/fractional gains anyway, something that even most pro drivers won't be able to tell a difference in a blind test.

0.02

 

[Chris_B]

Which drilled rotors are you referring to?

Regardless, for those buying replacement rotors, just go with slotted.

I know you're an AP dealer and continue to rave about the J-Hook slot design but show me data where they have 'practically the same bite as cross drilled and more than slotted'. You're talking micro/fractional gains anyway, something that even most pro drivers won't be able to tell a difference in a blind test.

0.02

Ones done properly, not the garden variety stuff normally sold by the cheap guys. For the street, slotted is nearly as good for most drivers, although many (including me) can easily tell the difference.

I'm not involved directly with AP Racing any longer, but still know the best and worst of what they make. No one brand is 100% magic for all applications.

Talk to your colleagues in Sprint Cup that have been testing brakes for the last 10 years or so. The J-Hooks were one of the few designs that showed promise on the brake dyno and were actually felt on the track. Many Grand Am and ALMS drivers will also concur. They definitely work, but, of course, not all pro drivers will notice the difference. Over the years, I've worked with some very sensitive brakers and some that thought the pedal was an anvil to be beat on. It really depends on who is behind the wheel when looking for small differences, as I'm sure you know very well.

Chris

 

[stuntman]

Ones done properly, not the garden variety stuff normally sold by the cheap guys. For the street, slotted is nearly as good for most drivers, although many (including me) can easily tell the difference.

Enlighten me You also must be a pretty good driver.

Talk to your colleagues in Sprint Cup that have been testing brakes for the last 10 years or so. The J-Hooks were one of the few designs that showed promise on the brake dyno and were actually felt on the track. Many Grand Am and ALMS drivers will also concur. They definitely work, but, of course, not all pro drivers will notice the difference. Over the years, I've worked with some very sensitive brakers and some that thought the pedal was an anvil to be beat on. It really depends on who is behind the wheel when looking for small differences, as I'm sure you know very well.

Chris

I agree with part of this but to quote someone whose been around the block once or twice "you're dealing with fly sh*t". True performance impact is negligible.

While AP is probably currently the post popular choice in Cup at the moment, if you look at what has been winning last year's road courses and short tracks, you'll probably find they werent that brand.

0.02

 

[Chris_B]

Enlighten me You also must be a pretty good driver.

I agree with part of this but to quote someone whose been around the block once or twice "you're dealing with fly sh*t". True performance impact is negligible.

While AP is probably currently the post popular choice in Cup at the moment, if you look at what has been winning last year's road courses and short tracks, you'll probably find they werent that brand.

0.02

I see we are diverging pretty far off topic. Fun for a bar room discussion, for sure, but the OP was most concerned (as are others) about how far they can push the factory Honda equipment.

I stand by my statements regarding properly drilled rotors for street / autocross / light track duty. For more serious outings, J-Hook or slotted is the way to go, of which the J-Hook provides a little more bite when that is desired. I'm not a big fan of dimpled rotors due to the aerodynamic effects of trying to squeeze air into a trapped space with no exit. Yes, they basically work, but there is a constant, yet small, force pushing back on the pad under heavy braking. You can tell Darrick D. I said that! :tongue:

And as far as determining how much of a difference to pay attention to: When my stopwatch (or DAG) says it is faster and my driver claims to have more confidence in the heavy braking zones, whatever we are using is better. Period. The fact that I may or may not be able to also feel a difference is anecdotal as I'm not the one being paid to take the win. :wink:

Chris

 

[stuntman]

I see we are diverging pretty far off topic. Fun for a bar room discussion, for sure, but the OP was most concerned (as are others) about how far they can push the factory Honda equipment.

I stand by my statements regarding properly drilled rotors for street / autocross / light track duty. For more serious outings, J-Hook or slotted is the way to go, of which the J-Hook provides a little more bite when that is desired. I'm not a big fan of dimpled rotors due to the aerodynamic effects of trying to squeeze air into a trapped space with no exit. Yes, they basically work, but there is a constant, yet small, force pushing back on the pad under heavy braking. You can tell Darrick D. I said that! :tongue:

And as far as determining how much of a difference to pay attention to: When my stopwatch (or DAG) says it is faster and my driver claims to have more confidence in the heavy braking zones, whatever we are using is better. Period. The fact that I may or may not be able to also feel a difference is anecdotal as I'm not the one being paid to take the win. :wink:

Chris

I'm still interested in hearing which drilled rotors are 'proper'.

In regards to 'squeezing air into a trapped space' argument - J-hooks have the same problems as do any slot that does not exit radially to the outer edge of the rotor (which most dont). IMO its an irrelevant point. Besides, dimpled rotors are not that brand's motorsport application anyway.

Subjectivity and expected outcomes do stray even the best to agree that "its better". It just depends on the test methods but at the end of the day, it might make one driver feel more comfortable to drive faster, but another can drive just as fast on other equipment. Slots are still "fly sh*t". Pad compounds make a far bigger impact on feel, response, modulation, initial bite, etc... Even there with far bigger differences in characteristics, while it may suit one driver's driving style better, another is just as fast on something else with no clear dominant pad.

0.02

 

[Chris_B]

I'm still interested in hearing which drilled rotors are 'proper'.

Ones made from better iron compositions, in resin core tooling, with curved vane cores, on Disematic machines, followed with proper thermal post-processing, drilled with a full-sweep face pattern and with holes finished by radius chamfering. I know many of Stillen's sport rotors are done this way. There are probably a few others, but not very many. I've tried for years to get companies to make them this way, but the sticking point is that if done 100% correct, very few in the market will actually spend the extra money. People talk quality all day long, but they buy with their hands on their wallets.

In regards to 'squeezing air into a trapped space' argument - J-hooks have the same problems as do any slot that does not exit radially to the outer edge of the rotor (which most dont). IMO its an irrelevant point. Besides, dimpled rotors are not that brand's motorsport application anyway.

The J-Hooks don't trap the air. It escapes as they pass by the pad's leading edges and out of the ramped end of the "J".

Subjectivity and expected outcomes do stray even the best to agree that "its better". It just depends on the test methods but at the end of the day, it might make one driver feel more comfortable to drive faster, but another can drive just as fast on other equipment. Slots are still "fly sh*t". Pad compounds make a far bigger impact on feel, response, modulation, initial bite, etc... Even there with far bigger differences in characteristics, while it may suit one driver's driving style better, another is just as fast on something else with no clear dominant pad.

Agreed!

Chris

 

[CL65 Captain]

People talk quality all day long, but they buy with their hands on their wallets.

It's hard to justify the money when we are talking about consumables - especially for a weekend track junkie. I will pay extra for quality, but there is a limit. 2x$? 3x$?

 

[stuntman]

I wouldn't necesarilly say that :redface:

EXACTLY. Contrary to popular belief (even many people at the club and even pro racing level), braking lighter and longer is NOT easier on the brakes. Reducing the brake zone by braking harder/threshold braking at the limit for a SHORTER period of time will have LESS rotor temperature, pad wear, fade than braking earlier, longer, and lighter.

This should have been brought up a lot sooner and emphasized. Sorry I didn't think about mentioning such a crucial piece of information, but good job picking up my slack!

Billy

After further enlightenment from a few engineers, I no longer take this standpoint on braking.

Braking earlier and lighter results in less peak heat generated and is 'easier on the brakes'.

The equation is energy over time. Given the same car at the same speeds, it will take the same energy to slow the car down. Increasing the braking distance, increases the amount of time it takes to expel the same amount of energy through the rotor. In addition, with longer braking, there will be more time for engine braking - energy to be spent through decelerating the transmission.

While braking longer, earlier, and lighter, the rotor has more time to cool down and expel the same amount of energy that it does in a shorter and briefer time. Braking later, harder, and shorter expels the same energy in a short period of time, so higher brake temps, less time to expel that energy -thus easier to fade the brakes, and harder on pad wear and brakes.

Imagine going 200mph and slamming on the brakes, engaging ABS all the way to a stop. Would your brakes fade? Would they be hot? Now imagine going 200mph, letting off the gas, slowly going to brakes (by this time you will lose probably 10mph or more from drag alone), then lightly on the brakes for a long time like you do when exiting an off-ramp on a highway. More time for the rotor to expel the energy, energy expelled from drag from the drivetrain and aerodynamics, and thus the brakes are not has hot.


You learn something new everyday.

 

[Juice]

Actually, this thread has taught me a lot today!

 

[stevenlee]

I've been following this thread with great interest.
I'll be tracking my car for the first time at NSXPO in a few months.
I have turbos producing roughly 550 whp and am running '97 OEM calipers and calipers with Hawk HPS pads.
Tires are Bridgestone RE 050. 235's in the front and 295's in the rear.
I was hoping to simply swap out the pads for the Performance Friction 06 pads mentioned by Billy. I'm wondering if the OEM rotors and calipers will be adequate. And if the PF 06 Pads will work OK on the rotors that have been running the HPS pads. If I use the PF 06 pads on my existing rotors, how should I prep the rotors for the different pad compound?
One consideration is that I'll be driving 2,500 miles to NSXPO and 2,500 miles back.
Any comments would be greatly appreciated.

 

[R13]

After further enlightenment from a few engineers, I no longer take this standpoint on braking.

Braking earlier and lighter results in less peak heat generated and is 'easier on the brakes'.

The equation is energy over time. Given the same car at the same speeds, it will take the same energy to slow the car down. Increasing the braking distance, increases the amount of time it takes to expel the same amount of energy through the rotor. In addition, with longer braking, there will be more time for engine braking - energy to be spent through decelerating the transmission.

While braking longer, earlier, and lighter, the rotor has more time to cool down and expel the same amount of energy that it does in a shorter and briefer time. Braking later, harder, and shorter expels the same energy in a short period of time, so higher brake temps, less time to expel that energy -thus easier to fade the brakes, and harder on pad wear and brakes.

Imagine going 200mph and slamming on the brakes, engaging ABS all the way to a stop. Would your brakes fade? Would they be hot? Now imagine going 200mph, letting off the gas, slowly going to brakes (by this time you will lose probably 10mph or more from drag alone), then lightly on the brakes for a long time like you do when exiting an off-ramp on a highway. More time for the rotor to expel the energy, energy expelled from drag from the drivetrain and aerodynamics, and thus the brakes are not has hot.


You learn something new everyday.

As I understood it the argument for compressing the braking zone (harder on the brakes for less time) was to maximize the amount of time that heat is not being added to the system which allows the brakes to cool more prior to re-application.

Have you been able to bear out this theory in your driving? I'm not good enough to provide a definitive data point here, but the only times I've run into fluid fade issues are when I was either A) new and still braking on the track like I would on the street (earlier and more gently over more time) or B) in traffic where I had to brake earlier and feather into it. In comparison, using the here-to-fore widely accepted "harder/shorter" technique, I have never had an issue.

Is this possibly different with the greater ducting efficiency on a racecar perhaps?

 

[latzke]

As I understood it the argument for compressing the braking zone (harder on the brakes for less time) was to maximize the amount of time that heat is not being added to the system which allows the brakes to cool more prior to re-application.

Have you been able to bear out this theory in your driving? I'm not good enough to provide a definitive data point here, but the only times I've run into fluid fade issues are when I was either A) new and still braking on the track like I would on the street (earlier and more gently over more time) or B) in traffic where I had to brake earlier and feather into it. In comparison, using the here-to-fore widely accepted "harder/shorter" technique, I have never had an issue.

Yes, I'm also skeptical about the degree stuntman's new theory fits with the real world - despite being reasonable, championed by well-intentioned engineers, and now held by a respected driver.

 

[MvM]

After further enlightenment from a few engineers, I no longer take this standpoint on braking.

Braking earlier and lighter results in less peak heat generated and is 'easier on the brakes'.

The equation is energy over time. Given the same car at the same speeds, it will take the same energy to slow the car down. Increasing the braking distance, increases the amount of time it takes to expel the same amount of energy through the rotor. In addition, with longer braking, there will be more time for engine braking - energy to be spent through decelerating the transmission.

While braking longer, earlier, and lighter, the rotor has more time to cool down and expel the same amount of energy that it does in a shorter and briefer time. Braking later, harder, and shorter expels the same energy in a short period of time, so higher brake temps, less time to expel that energy -thus easier to fade the brakes, and harder on pad wear and brakes.

Imagine going 200mph and slamming on the brakes, engaging ABS all the way to a stop. Would your brakes fade? Would they be hot? Now imagine going 200mph, letting off the gas, slowly going to brakes (by this time you will lose probably 10mph or more from drag alone), then lightly on the brakes for a long time like you do when exiting an off-ramp on a highway. More time for the rotor to expel the energy, energy expelled from drag from the drivetrain and aerodynamics, and thus the brakes are not has hot.

I respectfully would like to disagree.
Not only from my own experience but from a technical standpoint as well.

When I first tracked my car, I would do exactly as you stated above. I would be (very :smile early on the brakes, not brake very hard. As a result, of course, my times were slow and yet, I would experience brake fade very quicly.
Then, someone with a lot more experience than myself, showed be a better way: Brake as late as possible and as hard as possible. The result: Your average (lap)speed goes up and brake fade almost dissapeared completely.

Technically speaking, as you mentioned, when braking, the kinetic energy of your car is turned into heat by friction.
It therefore does not matter if you slow down from 100mph to 40mph in 10 seconds or in 5 seconds. IN BOTH CASES, the SAME AMOUNT of energy is transferred, ergo, in the end the SAME AMOUNT OF HEAT is being produced.
That said, of course, heating up your brakes in 5 seconds is probably harder on the material than doing the same in 10 seconds.
And also, of course, if you take 10 seconds to GENERATE THE SAME HEAT to your brakes, some of it will already have been dissipated to the air by the time those 10 seconds have passed.
The question is, just HOW MUCH HEAT you think will be dissipated to the air in just 5 seconds time while AT THE SAME TIME you are still braking.

Cooling your brakes does not happen when you are braking. It occurs when you are NOT braking at all.
Braking late and hard will in the end generate just as much heat as braking late and little, but especially taken over a few laps, the totale time your brakes will have to cool down will be significantly shorter.
Say your average track has 8 turns and an average laptime of 150 seconds (2.5 minutes). Say you take 8 seconds time for braking instead of 4 seconds.

Braking time long (8 seconds)
Total braking time (long): 8x8 = 64 seconds
You will be heating up your brakes for 64 seconds leaving only 86 seconds for them to cool off again.
So time are 64 heating up versus 86 seconds cooling down.

Braking time short (4 seconds):
Totale braking time (short) : 8x4 = 32 seconds.
COOL-DOWN time = 150 - 32 = 118 seconds.
Time are: 32 heating up versus 118 seconds cooling down.

Take your pick which scenario will lead to hotter brakes and more brake fade over a few laps.

 

[Chris_B]

After further enlightenment from a few engineers, I no longer take this standpoint on braking.

Braking earlier and lighter results in less peak heat generated and is 'easier on the brakes'.

The equation is energy over time. Given the same car at the same speeds, it will take the same energy to slow the car down. Increasing the braking distance, increases the amount of time it takes to expel the same amount of energy through the rotor. In addition, with longer braking, there will be more time for engine braking - energy to be spent through decelerating the transmission.

While braking longer, earlier, and lighter, the rotor has more time to cool down and expel the same amount of energy that it does in a shorter and briefer time. Braking later, harder, and shorter expels the same energy in a short period of time, so higher brake temps, less time to expel that energy -thus easier to fade the brakes, and harder on pad wear and brakes.

Imagine going 200mph and slamming on the brakes, engaging ABS all the way to a stop. Would your brakes fade? Would they be hot? Now imagine going 200mph, letting off the gas, slowly going to brakes (by this time you will lose probably 10mph or more from drag alone), then lightly on the brakes for a long time like you do when exiting an off-ramp on a highway. More time for the rotor to expel the energy, energy expelled from drag from the drivetrain and aerodynamics, and thus the brakes are not has hot.


You learn something new everyday.

I agree 100% with this post, based on both engineering theory and real world results. Energy has a time component built into it, which is exactly why torque and horsepower are related, but not the same thing.

Chris

 

[stuntman]

I respectfully would like to disagree.
Not only from my own experience but from a technical standpoint as well.

When I first tracked my car, I would do exactly as you stated above. I would be (very :smile early on the brakes, not brake very hard. As a result, of course, my times were slow and yet, I would experience brake fade very quicly.
Then, someone with a lot more experience than myself, showed be a better way: Brake as late as possible and as hard as possible. The result: Your average (lap)speed goes up and brake fade almost dissapeared completely.

Technically speaking, as you mentioned, when braking, the kinetic energy of your car is turned into heat by friction.
It therefore does not matter if you slow down from 100mph to 40mph in 10 seconds or in 5 seconds. IN BOTH CASES, the SAME AMOUNT of energy is transferred, ergo, in the end the SAME AMOUNT OF HEAT is being produced.
That said, of course, heating up your brakes in 5 seconds is probably harder on the material than doing the same in 10 seconds.
And also, of course, if you take 10 seconds to GENERATE THE SAME HEAT to your brakes, some of it will already have been dissipated to the air by the time those 10 seconds have passed.
The question is, just HOW MUCH HEAT you think will be dissipated to the air in just 5 seconds time while AT THE SAME TIME you are still braking.

Cooling your brakes does not happen when you are braking. It occurs when you are NOT braking at all.
Braking late and hard will in the end generate just as much heat as braking late and little, but especially taken over a few laps, the totale time your brakes will have to cool down will be significantly shorter.
Say your average track has 8 turns and an average laptime of 150 seconds (2.5 minutes). Say you take 8 seconds time for braking instead of 4 seconds.

Braking time long (8 seconds)
Total braking time (long): 8x8 = 64 seconds
You will be heating up your brakes for 64 seconds leaving only 86 seconds for them to cool off again.
So time are 64 heating up versus 86 seconds cooling down.

Braking time short (4 seconds):
Totale braking time (short) : 8x4 = 32 seconds.
COOL-DOWN time = 150 - 32 = 118 seconds.
Time are: 32 heating up versus 118 seconds cooling down.

Take your pick which scenario will lead to hotter brakes and more brake fade over a few laps.

Braking late, brief, and hard will not generate the same peak heat as earlier, lighter, and longer. It will dissipate the same energy but spread out over time will result in a lower peak temperature. Despite a shorter time to cool the rotor in the early/light braking example, the rotor's starting temp will be lower due to the less heat generated from the longer and lighter stop.

The equation is energy over time.

Another example:

A proper racecar can slow down from 140mph in a very short time, glowing the rotors with rotor temps well above 1,000*F. The average joe going 140mph will probably not brake as late or hard (or have the tire to generate the decel rates) of the racecar and won't glow the rotors. Joe shmo on street pads going 140mph on the highway will not generate the same rotor temps trying to slow down which the stock street pads will not operate at anyway. Thus the same heat is not generated between braking early and light or late and hard.

 

[R13]

So really, the theoretical situation you're talking about isn't necessarily focused on an on-track situation, but rather a generalization regarding brake physics across all uses.

Since the fast way around would usually not involve earlier/lighter braking because the goal on a track would be to get from terminal straight speed to maximum possible corner speed as quickly as possible.

 

[MvM]

Braking late, brief, and hard will not generate the same peak heat as earlier, lighter, and longer. It will dissipate the same energy but spread out over time will result in a lower peak temperature. Despite a shorter time to cool the rotor in the early/light braking example, the rotor's starting temp will be lower due to the less heat generated from the longer and lighter stop.

The equation is energy over time.

Another example:
A proper racecar can slow down from 140mph in a very short time, glowing the rotors with rotor temps well above 1,000*F. The average joe going 140mph will probably not brake as late or hard (or have the tire to generate the decel rates) of the racecar and won't glow the rotors. Joe shmo on street pads going 140mph on the highway will not generate the same rotor temps trying to slow down which the stock street pads will not operate at anyway. Thus the same heat is not generated between braking early and light or late and hard.

I agree ABSOLUTELY with you that you peak rotor temperatures will be higher in the Brake Late/Brake Hard scenario than when taking it easy.

But I DISAGREE with you about the 'same heat point'.
Assuming that you will be slowing down FROM the same speed TO the same speed using the brakes (from 140mph to 40mph for example) using the brakes, you WILL generate EXACTLY the same heat.
Your car's kinetic energy is transformed into heat. Transform the same kinetic energy will generate the same amount of heat. Period!. It is what is called the First law of Thermodynamics.
Mind you, this says nothing about your peak temperatures off course.