Generation IV Internal Engine - LS2 Power Loss

what percent of power loss is it from the Flywheel to the Rear wheels ? I had an LS1 before and im going to the LS2 engine what do you think my RWHP will be putting the LS2 Stock Crate engine in my 99 TA with only Headers ? and no EGR

ummmm, Seriously... 420 * 80%= 360... well, that's a lil off, but should be close...