Fuel pressure Reg. Question

[rbrthrly900]

Ok, so going to be getting an AFPR soon... Question is I have never messed with one before... So when I get it and bolt it in what am I looking for... I am assuming that it is not just direct plug and play... Some adj. will need to be made... But what??? It has a gauge on it... What should it read, and when??? I cant look at it when driving... so how do I check it, and make sure it is doing what it should be doing??? Thank you for your input... I am just very curious as to how these really work, and google does not give me a very good answer....

[RoadWarrior222]

Base pressure, with the vacuum hose unplugged (No boost or vacuum compensation) would be 55psi stock... when the hose is plugged in, that pressure compensates the fuel pressure, works against a diaphragm, that is spring biased so it goes lower in vacuum and higher in boost. The adjuster alters the spring tension, to alter base pressure. It maintains pressure by bleeding off excess pressure from the pump. Pumps tend to max at 100-120PSI IIRC.... so setting your base pressure higher than 65-70ish will probably not work too well as you'll max out the pump pressure and run lean at the worst place to run lean. Really they are good for fine tuning, not getting gobs more fuel. i.e. if you have stock injectors and want to run an output level that needs +40 injectors... get +40 injectors.

[rbrthrly900]

I have +20... Planning on one day in the future getting the +40s... So basically, when I get the afpr I need to do nothing but hook it up... should already be good to go...

[RoadWarrior222]

No, you'd have to set it to 55 for a start, then everything should run as it is now, then you can fiddle from there.