SPEC'a new shim question
 

I just purchased a new SPEC 3 clutch. It came with a slave shim so the question is. Should I still do the drill mod or is this SPEC's answer to LS1 clutch release/engagement problems?

I was told by spec to still use the shim.

I figured on the shim part but should I still go ahead with the drill mod?

Yes, use the shim and do the drill mod also.

the shim and the drill mod are 2 completely different things, the shim moves the slave closer to the pressure plate so that engagement of the clutch is not on the floor, its their answer to install the clutch with the stock non adjustable master. the drill mod increases fluid flow and will stop the loss of pedal pressure at high rpms. do both :)