What benefits do slotted & drilled rotors offer?

That's normal that the pads don't sweep the entire rotor, not a problem at all. He has the pads correct, the larger ones arae for a front PBR caliper, JL9, J55 or 1LE. The rears are for the pbr rear parking brake combo calipers for the same brake options.
Front rotors are 13x1.1 rears are 12x.83
But doesn't that kind of defeat the purpose? I mean aside from a little extra leverage, why the hell would you want a pad that small on a rotor with that much unused surface area?
 
Brake torque from increased leverage is quite a difference, also the j55 rotor is a lot thicker so the bigger mass means that the mean running temp is lower.
Brake force is not dependant on pad size, if you look up the formula for friction there is no contact area in it. The only difference a larger pad makes is that it transfers the kinetic energy into heat energy over a larger surface and therefore the local temps are a lot lower and this reduces the chance of pad fade. Bigger pads -> less fade... but if there is no brake fade with a setup with small pads the bigger pads have no bonus if they both have the same coeff. of friction and clamping force (piston sizes, master size, pedal ratio and pedal force) in other words, if I were to stick larger pads in those calipers with the rest all the same, pads made from same material it would NOT!!! brake better unless the other pads are too small and allow for pad fade under the conditions you are using them in.
 
Brake torque from increased leverage is quite a difference, also the j55 rotor is a lot thicker so the bigger mass means that the mean running temp is lower.
Brake force is not dependant on pad size, if you look up the formula for friction there is no contact area in it. The only difference a larger pad makes is that it transfers the kinetic energy into heat energy over a larger surface and therefore the local temps are a lot lower and this reduces the chance of pad fade. Bigger pads -> less fade... but if there is no brake fade with a setup with small pads the bigger pads have no bonus if they both have the same coeff. of friction and clamping force (piston sizes, master size, pedal ratio and pedal force) in other words, if I were to stick larger pads in those calipers with the rest all the same, pads made from same material it would NOT!!! brake better unless the other pads are too small and allow for pad fade under the conditions you are using them in.

You just explained why dynalites are fine. You don't need big honkin calipers with huge pads.
 
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