Are you talking about a boosted car? a single gt pump is not going to get you to 600. Not even with a BAP. I have a buddy with a mach 1 eaton and gt pump that made close to 450 and duty cycle was almost 100%...96 or 97% something like that. They backed off the tune to about 430 hp to lower the duty cycle a bit to stay on the safe side.
I'm going with dual gt pumps, dual fpdm's, 60's and wiring upgrade from battery to fpdm and from fpdm to pumps. Shooting for at least 550hp through my 2v with a D1SC.