I have a 383 lt1 with le2 heads and cam with bored intake and 58mm throttle body. That said I bought 36 lb injectors and a walbro 255 fuel pump. the motor was set up for a 11.5-1 ratio. Do I need to replace the stock regulator or will the stock pressure work just fine? Cam specs if needed are 235/243 .579/0.597 lsa 110

 

36 #/HR injectors are good for at least 515 flywheel HP, running at the stock (43.5psi = 3 bar) fuel pressure. That assumes the injectors were flow rated at that pressure. If you feel you will exceed 515 HP, get larger injectors. 42's are good for 600 flywheel HP.

If you tried to make 600 HP on the 36's, you would have to crank the fuel pressure up to 59.2 psi. And the flow constants in the tune would have to reflect that increased injector flow rate.