Alright, I've been noticing this recently, but I can't say for certain that this is a new issue. After I take a hard corner without using the brakes, later when I go to brake, the pedal sinks an inch further than normal before it builds pressure. After I hit the brakes once, they are fine. My master cylinder is a LS1 style, as are my rear brakes. Otherwise stock. Brake reservoir is plenty full Any ideas?

No one else has this happen?

Pad knock back. Happens for several reasons. Deflection in the brake mounting points will do it. Deflection in the axle flange allowing the rotor to 'tip'. Along with too much real axle end play.

Check the caliper pins and guides and such. Allowing the caliper to freely float helps in this regard.

RBob.

Ahh that makes perfect sense! Thanks

what he said. check the pins, make sure the calipers still glide on them and are not seized. Only takes 1 caliper to cause this problem

Also check front wheel bearings.