krahmlow

The rears are locking up under braking, and that's not even under really hard braking either. It started after I did the entire system--rebuilt all calipers, replaced all pads and rotors, replaced the master cylinder, and flushed the system with new fluid. I've bled the system again, just in case there was some air in the front lines, but no luck. Any ideas?

mmmbeer

If you were to put the front calippers on the rear hubs/brakes and the rear calippers on the front this problem would arise due to the larger pistons in the front calippers. At least this is true for the later 944/968 with Brembo's. I don't remember how it is on a 944 S, but I would imagine the front calippers to have a larger piston than the rears.

Eric_Oz_S2

What bias valve is on the master cyclinder? Should be 5/18 as standard. Perhaps it has been changed to a 5/33?

Have you lowered the rear suspension? Can cause slight change to brake balance.

krahmlow

Thanks for the ideas, but the calipers are as they should be. The bias valve is correct, too.... Any other suggestions?

JerryW

What pads are you running ? In the 944Spec cars we often see this when running the same pads (Hawk Blues mainly) front and rear. Solution is to run a slightly lesser pad in the rear (eg Blues front and HP+ rear or HT10's front and Blues rear)

However this is under hard braking.