F/R brake temperature?

Originally Posted by 2011 Nismo#91

If your not having brake issues then don't fix your brakes.

Originally Posted by cv129

Don’t know if Obender was measuring caliper or rotor temps.

For rotor temp measurement after a cool down lap, assume OEM Akebonos and no brake cooling ducts: the front rotors are just tiny bit bigger than the rear in diameter (355 vs 350mm), but thickness differs greatly (32mm vs 20mm). The front rotors carry a much greater volume of heat with not much more surface area to for heat dissipation. With a method like using an infrared temp gun, which measures surface temp, I would not be surprised there is a temp difference, even if the peak temp during braking may be the same between front and rear rotors.

Originally Posted by ValidusVentus

Indeed. To expand on that a bit; the ideal brake balance of the car is dictated by how much traction is available at either end of the car under maximum braking. The traction available is dictated by the tires, weight balance of the car, and the weight transfer that takes place at maximum braking. The amount of weight transfer is dictated by the wheelbase length, the weight of the vehicle and the rate of deceleration.


In effect this means that with grippier tires, more weight transfer will take place and the front brakes should be, and will be able to, do comparatively more of the braking work since they have more weight over their tires. Conversely, with less grippy tires or when its raining, at maximum braking, less weight transfer will take place (because you cant brake as hard) and a setup where there is less of a front biased braking force -still front biased though- will then provide the most overall braking ability. That's why, a bit counter-intuitively imo, racecars or cars with adjustable brake bias like mine need to run more rear bias in the wet than in the dry to maximize their braking capability.

Originally Posted by obender66

Yes, there was some cool down, and I agree, they cool off differently. My fronts probably cool off quicker as they are Wilwood 2 piece with aluminum hats and rear are off the shelf Z33 brembos.
I expect to see rears to be cooler, but question is how much cooler? Thank you for AP Racing link-they do not give precise answer, and it cannot be precise due to all the parameters mentioned by other posters. It's understood, but 40%?