Ate gt3 slotted rotors on the 996tt
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+1 997 rotors + a spacer (I think vivid sells the kit that includes a longer bolt). Or just go straight to the 997 rotors and calipers.
My understanding is the offset of a 997 Turbo rotor has the same offset as 996 Turbo, although they are different in rotor size (350mm vs. 330mm).
Have you ever tried a 997 turbo stock rotor instead of GT3 / Cayenne rotor??
Also do you know if Vivid Racing sells the spacer kit separately or must purchase the whole upgrade kit, if so how much?
Have you ever tried a 997 turbo stock rotor instead of GT3 / Cayenne rotor??
Also do you know if Vivid Racing sells the spacer kit separately or must purchase the whole upgrade kit, if so how much?
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I am not a fan of using smaller pad surface on bigger face rotor. IMO causes premature failure of the rotor if you are using them on the track. My 330 MM rotors have lasted longer than 355 mm rotors of the same kind for this very reason.
Aren't 997 TT rotors like almost $500 or more for two of them?
Aren't 997 TT rotors like almost $500 or more for two of them?
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6 pods
just feeding this thread. I spoke with a highly trusted tuner in the North East today who suggested motorsport cup 6-pod calipers and ATE 350mm rotors wich together present no offset issues all for the cost of others two piece rotors, and the bonus is that the ATE replacement rotors are less than the ring replacements on any two piece rotors out there.
Seems like a good path. I am checking into it further as this tuner really seems to know his stuff.
Will report back on my final decision and the results.
Seems like a good path. I am checking into it further as this tuner really seems to know his stuff.
Will report back on my final decision and the results.
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[quote=heavychevy;3433856]I am not a fan of using smaller pad surface on bigger face rotor. IMO causes premature failure of the rotor if you are using them on the track.[quote]
I could not see how or why that would happen considering that the heat generated is relative to the size of the friction area but a larger rotors increased surface area lends itself to higher heat dissapation.
Plus no matter how you look at it a larger diameter rotor will result in stronger brakes.
I could not see how or why that would happen considering that the heat generated is relative to the size of the friction area but a larger rotors increased surface area lends itself to higher heat dissapation.
Plus no matter how you look at it a larger diameter rotor will result in stronger brakes.
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[QUOTE=Engine Guy;3434767][quote=heavychevy;3433856]I am not a fan of using smaller pad surface on bigger face rotor. IMO causes premature failure of the rotor if you are using them on the track.
I could not see how or why that would happen considering that the heat generated is relative to the size of the friction area but a larger rotors increased surface area lends itself to higher heat dissapation.
Plus no matter how you look at it a larger diameter rotor will result in stronger brakes.
Not really, no it doesn't. Your brakes don't get stronger unless you increase the pressure to them. It's the same brake system pushing 4 pots or 6 pots so even on the 6 pots the pressure is spread out over a larger surface area and more pistons vs more concentrated over a smaller one so the pressure is weaker per piston on the 6 pot. The 4 pots are pressing significantly harder at each point given the same pressure. And your car will not have any more braking pressure with the 6 pots. What it will have is more resistance to heat soak (soft pedal) and more durability. This is assuming the same type of caliper (Porsche vs Porsche).
The heat generated is exactly the problem, you have one part of the rotor expanding during heat and shrinking when cooling down and the other part not even hardly in the same temperature zone because it's freely spinning exposed to air the entire time. Inconsistencies in the rate of expansion and contraction are what cause metal to crack. I've seen rotors crack (huge crack) prematurely at exactly where the 4 pot caliper pad ended on the 355 mm rotor. I think there is a limit to how big you can go on a rotor disk and still maintain the integrity of the rotor with the significantly smaller caliper. I would not do it if I track the car hard.
There is a reason no one designs rotors with pad surface area smaller than the rotor friction area. Plus over time you're dealing with two different thicknesses of metal, and the thinner metal is soaking up heat even faster every time you brake. Again, my data on this is limited, and this is theory, but I'm willing to bet it happens again and again, while my same pad on smaller friction area, keeps on rolling.
I could not see how or why that would happen considering that the heat generated is relative to the size of the friction area but a larger rotors increased surface area lends itself to higher heat dissapation.
Plus no matter how you look at it a larger diameter rotor will result in stronger brakes.
Not really, no it doesn't. Your brakes don't get stronger unless you increase the pressure to them. It's the same brake system pushing 4 pots or 6 pots so even on the 6 pots the pressure is spread out over a larger surface area and more pistons vs more concentrated over a smaller one so the pressure is weaker per piston on the 6 pot. The 4 pots are pressing significantly harder at each point given the same pressure. And your car will not have any more braking pressure with the 6 pots. What it will have is more resistance to heat soak (soft pedal) and more durability. This is assuming the same type of caliper (Porsche vs Porsche).
The heat generated is exactly the problem, you have one part of the rotor expanding during heat and shrinking when cooling down and the other part not even hardly in the same temperature zone because it's freely spinning exposed to air the entire time. Inconsistencies in the rate of expansion and contraction are what cause metal to crack. I've seen rotors crack (huge crack) prematurely at exactly where the 4 pot caliper pad ended on the 355 mm rotor. I think there is a limit to how big you can go on a rotor disk and still maintain the integrity of the rotor with the significantly smaller caliper. I would not do it if I track the car hard.
There is a reason no one designs rotors with pad surface area smaller than the rotor friction area. Plus over time you're dealing with two different thicknesses of metal, and the thinner metal is soaking up heat even faster every time you brake. Again, my data on this is limited, and this is theory, but I'm willing to bet it happens again and again, while my same pad on smaller friction area, keeps on rolling.
Last edited by heavychevy; Jan 24, 2012 at 01:06 AM.
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It confounds me how some are willing to compromise the primary safety system of the vehicle by arbitrarily grinding on parts of it that they don't understand.
First, the pins on the caliper are what support the pads and transfer all of the braking forces into the caliper body. The length of them is such that at full pad and disc wear the pads are still supported.
If the disc is off center, this is no longer the case, and when the parts are worn, the engagement between the pin and pad can become small enough to damage the caliper, or the pad can move past the pin entirely causing much greater problems.
Furthermore, if the disc is off center, on the side where the gap is larger, at full wear the piston will have moved out farther than the system was designed for. If this change is enough to move the piston past the seal, then complete brake system failure is the result.
Finally, heavychevy is correct regarding unswept disc area. This increases the thermal stresses in the disc as the swept area heats up much more and much more quickly. Premature cracking can be the result.
First, the pins on the caliper are what support the pads and transfer all of the braking forces into the caliper body. The length of them is such that at full pad and disc wear the pads are still supported.
If the disc is off center, this is no longer the case, and when the parts are worn, the engagement between the pin and pad can become small enough to damage the caliper, or the pad can move past the pin entirely causing much greater problems.
Furthermore, if the disc is off center, on the side where the gap is larger, at full wear the piston will have moved out farther than the system was designed for. If this change is enough to move the piston past the seal, then complete brake system failure is the result.
Finally, heavychevy is correct regarding unswept disc area. This increases the thermal stresses in the disc as the swept area heats up much more and much more quickly. Premature cracking can be the result.
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Well where do I begin, or even do I.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
Not really, no it doesn't. Your brakes don't get stronger unless you increase the pressure to them. It's the same brake system pushing 4 pots or 6 pots so even on the 6 pots the pressure is spread out over a larger surface area and more pistons vs more concentrated over a smaller one so the pressure is weaker per piston on the 6 pot. The 4 pots are pressing significantly harder at each point given the same pressure. And your car will not have any more braking pressure with the 6 pots. What it will have is more resistance to heat soak (soft pedal) and more durability. This is assuming the same type of caliper (Porsche vs Porsche).
The heat generated is exactly the problem, you have one part of the rotor expanding during heat and shrinking when cooling down and the other part not even hardly in the same temperature zone because it's freely spinning exposed to air the entire time. Inconsistencies in the rate of expansion and contraction are what cause metal to crack. I've seen rotors crack (huge crack) prematurely at exactly where the 4 pot caliper pad ended on the 355 mm rotor. I think there is a limit to how big you can go on a rotor disk and still maintain the integrity of the rotor with the significantly smaller caliper. I would not do it if I track the car hard.
There is a reason no one designs rotors with pad surface area smaller than the rotor friction area. Plus over time you're dealing with two different thicknesses of metal, and the thinner metal is soaking up heat even faster every time you brake. Again, my data on this is limited, and this is theory, but I'm willing to bet it happens again and again, while my same pad on smaller friction area, keeps on rolling.
The heat generated is exactly the problem, you have one part of the rotor expanding during heat and shrinking when cooling down and the other part not even hardly in the same temperature zone because it's freely spinning exposed to air the entire time. Inconsistencies in the rate of expansion and contraction are what cause metal to crack. I've seen rotors crack (huge crack) prematurely at exactly where the 4 pot caliper pad ended on the 355 mm rotor. I think there is a limit to how big you can go on a rotor disk and still maintain the integrity of the rotor with the significantly smaller caliper. I would not do it if I track the car hard.
There is a reason no one designs rotors with pad surface area smaller than the rotor friction area. Plus over time you're dealing with two different thicknesses of metal, and the thinner metal is soaking up heat even faster every time you brake. Again, my data on this is limited, and this is theory, but I'm willing to bet it happens again and again, while my same pad on smaller friction area, keeps on rolling.
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+1 what he said
Well where do I begin, or even do I.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
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It confounds me how some are willing to compromise the primary safety system of the vehicle by arbitrarily grinding on parts of it that they don't understand.
First, the pins on the caliper are what support the pads and transfer all of the braking forces into the caliper body. The length of them is such that at full pad and disc wear the pads are still supported.
If the disc is off center, this is no longer the case, and when the parts are worn, the engagement between the pin and pad can become small enough to damage the caliper, or the pad can move past the pin entirely causing much greater problems.
Furthermore, if the disc is off center, on the side where the gap is larger, at full wear the piston will have moved out farther than the system was designed for. If this change is enough to move the piston past the seal, then complete brake system failure is the result.
First, the pins on the caliper are what support the pads and transfer all of the braking forces into the caliper body. The length of them is such that at full pad and disc wear the pads are still supported.
If the disc is off center, this is no longer the case, and when the parts are worn, the engagement between the pin and pad can become small enough to damage the caliper, or the pad can move past the pin entirely causing much greater problems.
Furthermore, if the disc is off center, on the side where the gap is larger, at full wear the piston will have moved out farther than the system was designed for. If this change is enough to move the piston past the seal, then complete brake system failure is the result.
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I see a whole lot of theorizing, have you actually had both on your 996 Turbo??? I have. and the 6 piston actually take MORE pedal effort to achieve the same amount of braking effort. The 4 pistons bite harder and quicker. And this has been mirrored by others who have tracked both setups. And then again you are assuming I'm talking about stock rotors that are smaller in diameter. What about the SAME rotor, which will have a bigger weight gap to the 350 mm aftermarket rotor than it did with the stock rotor at 350 mm??? So even more unsprung weight loss..... I have them all, weighed them all.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
Well where do I begin, or even do I.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
These larger discs are actually better for several reasons; they are almost always lighter then the OEM discs they replace. So just due to the inertia alone there is a gain; plus there ability to shed heat and the extra time it takes to heat up
As per the braking force. Well that is a complex topic but I will simplify it and only cover some basics.
It is the same caliper and the same pressure yes, But where more braking force is gained is gain is in the diameter; the extra diameter acts like a larger lever arm. Larger lever, larger force or stopping power.
These rotors we are talking about generally do not have an un-touched braking surface area. The height of the swept area is the same on both the big rotors and on the smaller ones. There is a problem that does exist but it is not of a grave serious nature at anything but the elite levels of braking. And that problem is slightly decreased tag and crown surface contact due to the different shape requirements of each rotor size. Basically the top and bottom portion of the pad do not contact the rotor along the entire length of the pad in the same circumference arc. The arc of the pad does not follow the arc of the rotor so at the top and the bottom of the pad there is less pad contact or swept area in those spots, so you will have some slight uneven wear. Not a huge problem for a brake system that is not pushed to 100% all the time. And even if it was you would be dealing with items that would be thrown out very frequently so it would not be that big and issue.
Now is this design principle ideal... No it is not, but is a way for some cheap Porsche driver to get significantly better brakes on a budget. Yes it is.
If it were my race car and I had to make a living by taking care of every detail I would not do this. But on my road car that see's some track for fun then why not.
Companies like Girodisc know this, that’s why they will make a bigger rotor for the smaller caliper yet still sleep soundly at night know that they did not risk anyone’s life by doing such.
Last edited by heavychevy; Jan 27, 2012 at 03:02 PM.
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I am not theorizing, lets just say I have been around a few race tracks being a race shop owner and former automotive design engineer I understand this subject.
I myself was not talking pistons from four to six. I was talking 996TT brakes with both a 330mm rotor and also a 350mm.
But you are talking about an overall knowledge of just what you have used. I can start spewing formulas if you want, I know them by rote.
Clamping force comes down to not how many pistons a brake caliper has but to combined piston area and the area of the brake pad. This all is directly related to brake force and overall stopping power. Now Porsche may use any number of pistons and get the same overall clamping forces but it all comes down to system design and what you want to acheive.
As per the intermediate drive to a pro.. Well sure a pro running the same speeds or maybe even a bit faster than an intermediate will likely use less brake. But you get any racer up to speed then you have the good old glowing rotor moments.
In my opinion a not only are there some leverage ratio gains from bigger rotors there is also heat transferance... But and there are always buts; there are many other variables to consider in a complete system and I do not want to debate this Please share your vast experience with companies like Girodisc and Brembo and the likes; both of which make 350mm kits with spacers for OEM rotors for the 996.
Maybe you or Al are the brake riding newbs that scorched a set of rotors.... I do not know, also I do know that porsches stability braking system can place a high demand on a brake set up when used at the track...
All I know is what I have seen from many thousands of KM's on the track and in the shop.
I myself was not talking pistons from four to six. I was talking 996TT brakes with both a 330mm rotor and also a 350mm.
But you are talking about an overall knowledge of just what you have used. I can start spewing formulas if you want, I know them by rote.
Clamping force comes down to not how many pistons a brake caliper has but to combined piston area and the area of the brake pad. This all is directly related to brake force and overall stopping power. Now Porsche may use any number of pistons and get the same overall clamping forces but it all comes down to system design and what you want to acheive.
As per the intermediate drive to a pro.. Well sure a pro running the same speeds or maybe even a bit faster than an intermediate will likely use less brake. But you get any racer up to speed then you have the good old glowing rotor moments.
In my opinion a not only are there some leverage ratio gains from bigger rotors there is also heat transferance... But and there are always buts; there are many other variables to consider in a complete system and I do not want to debate this Please share your vast experience with companies like Girodisc and Brembo and the likes; both of which make 350mm kits with spacers for OEM rotors for the 996.
Maybe you or Al are the brake riding newbs that scorched a set of rotors.... I do not know, also I do know that porsches stability braking system can place a high demand on a brake set up when used at the track...
All I know is what I have seen from many thousands of KM's on the track and in the shop.
I see a whole lot of theorizing, have you actually had both on your 996 Turbo??? I have. and the 6 piston actually take MORE pedal effort to achieve the same amount of braking effort. The 4 pistons bite harder and quicker. And this has been mirrored by others who have tracked both setups. And then again you are assuming I'm talking about stock rotors that are smaller in diameter. What about the SAME rotor, which will have a bigger weight gap to the 350 mm aftermarket rotor than it did with the stock rotor at 350 mm??? So even more unsprung weight loss..... I have them all, weighed them all.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
Last edited by Engine Guy; Jan 27, 2012 at 07:31 PM.
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I see a whole lot of theorizing, have you actually had both on your 996 Turbo??? I have. and the 6 piston actually take MORE pedal effort to achieve the same amount of braking effort. The 4 pistons bite harder and quicker. And this has been mirrored by others who have tracked both setups. And then again you are assuming I'm talking about stock rotors that are smaller in diameter. What about the SAME rotor, which will have a bigger weight gap to the 350 mm aftermarket rotor than it did with the stock rotor at 350 mm??? So even more unsprung weight loss..... I have them all, weighed them all.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
Your comments about braking are false, because an intermediate at a DE will be significantly harder on brakes than an pro will because a pro will hit the brakes not harder, but later and far shorter because they will carry FAR more speed into the corner, and out of the corner down the next straight for cooling while the top speeds on the straights will be similar given the same car.
If Al still has his rotors I will post pics that SHOW what I'm talking about.
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None of what engine guy said is incorrect. You're simply talking about something else, pedal feel is a separate issue from system torque gain (i.e. Nm brake torque per unit of fluid pressure). As you have noticed, a 6 piston setup with the same piston area as a 4 piston setup will result in different pedal feel. This is for all kinds reasons, including caliper stiffness, total seal area, and piston displacement. Apples and oranges...
Let me ask this question since engine guy obviously has not tracked both. Have you tracked both on your 996 TT?
I have data also that shows earlier engagement of ABS with 4 piston system both with pedal to floor, or is that feel too?