Just wondering if I really need a aftermarket adjustable pressure regulator. Or Should I just leave the stock one . I have a built 383 76 mm turbo looking to make 650/ 700rwhp. Have twin intank pumps with hobbs switch. If I need more or less fuel it would be changed in the pcm anyway wouldnt it ? Or is it best to have one ? thanks
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What year/engine are you asking about? You really need to make a "Signature" with basic info about your car - year, model, engine, tranny and any major mods. What you have there now is not very useful, and may explain why you aren't getting any help.
Let's assume you have an LT1. You need to decide what fuel pressure you want to run. Stock pressure regulator controls the pressure (difference between rail pressure and intake manifold pressure) at 43.5psi. With a high HP application you may want to run at a higher pressure. That helps you keep the injector size down. Also offers benefits in minimizing the changes in pressure resulting from sudden acceleration/G-forces (important for a drag application). It isn't unusual to run at 58psi (4 bar or higher), but your pumps have to be able to produce adequate flow at that pressure. Many pumps lose significant flow capacity above 45psi or so. To run higher pressures, in addition to an adjustable fuel pressure regulator, you need a pump that is "high pressure" rated, to insure adequate flow. You also need to have injectors of the correct type, that will tolerate the higher pressure. 58psi isn't really a problem - that's the stock pressure for the LT1 engines - but you still have to insure you have a pump (or pumps) that will continue to flow adequat capacity at the higher pressure.
Yes... you "tune" in the PCM, not with an AFPR. But an AFPR would allow you to run your system at higher pressure, with smaller injectors, and more uniform fuel pressure under dynamic conditions.
Let's assume you have an LT1. You need to decide what fuel pressure you want to run. Stock pressure regulator controls the pressure (difference between rail pressure and intake manifold pressure) at 43.5psi. With a high HP application you may want to run at a higher pressure. That helps you keep the injector size down. Also offers benefits in minimizing the changes in pressure resulting from sudden acceleration/G-forces (important for a drag application). It isn't unusual to run at 58psi (4 bar or higher), but your pumps have to be able to produce adequate flow at that pressure. Many pumps lose significant flow capacity above 45psi or so. To run higher pressures, in addition to an adjustable fuel pressure regulator, you need a pump that is "high pressure" rated, to insure adequate flow. You also need to have injectors of the correct type, that will tolerate the higher pressure. 58psi isn't really a problem - that's the stock pressure for the LT1 engines - but you still have to insure you have a pump (or pumps) that will continue to flow adequat capacity at the higher pressure.
Yes... you "tune" in the PCM, not with an AFPR. But an AFPR would allow you to run your system at higher pressure, with smaller injectors, and more uniform fuel pressure under dynamic conditions.