I have a 97 trans am, with 3.42 gears 2800 stall, full exhaust and light engine mods, plus a tuner. If I were to get a Fuel Pressure regulator how much over the stock PSI should I go? Any input would help. Thanks

No more than 5psi above stock, and don't expect to see any gains from that either. GM's F/I is set up pretty well from the factory, they eeked out the most performance they could with the parts they used.