I just purchased an adjustable fuel pressure regulator, and wanted to know if there are any recommendations on what to set the base pressure to. What is stock pressure, and if anyone has messed with this before and found a good setting for a slightly modified motor (open exhaust, and no smog equipment). Also, should I hook the Vacuum port up to the original vacuum line out of the fuel pressure solenoid or use straight vacuum? any help would be great,

Thanks,

- Josh

 

Stock is about 28psi at the rail with the car running (idle). I would hook the vac line straight manifold vaccum and just remove the vacuum solenoid. What the vacuum solenoid does is to make the fuel pressure regulator reference atmospheric pressure (instead of manifold vac) during hot starts (and just after a hot start). This bumps the fuel pressure to about 37 psi for about 1 minute, if I remember correctly. It is supposed to help prevent vapor lock, I guess.

Anyway, set it to 30-35 psi with the car at idle. That will get you a little more fuel to help feed it up top. You can then adjust from there as needed. You won't gain a lot of injector capacity by increasing pressure, but will gain some.

 

Perfect, I will start there, and adjust accordingly.

Thanks