how much can fuel pressure regulator hold?

[silver Mr2]

does anybody know what the fuel pressure regulator holds (psi) what's the max it could take?

[DWF Engineering]

I don't know about the MKII but the MKI's inspection tolerance is 33-38 psi and the optimum is 35 psi, I think. I know thats right +/- 1 psi though. If you get an adjustable FPR you'll be able to crank it to about 55 psi on the stock pump. When you go to the adjustable FPR your need to find a shop to make a fitting that eliminates the stock regulator. This is what I did with my MKI:

stock: 16.5 @ 84
de-catted: 16.4@ 84
Supertrapp: 16.1 @ 85
"powermax": 15.9 @ 86
cold/ram air box: 15.7 @ 87
adjustable FPR/tuning: 15.3 @ 89
web cams #577: 15 @ 92

A header would be a good mod to follow the cams; you can also get good results with a polished/honded stock manifold. I would do the same with the intake. I never went past the cams due to an engine compartment fire however; I wanted to cry.



P.S. If you have an older US spec 4A-GE don't listen to shops saying they can give you more power with port and polish; they don't know the 4A-GE head! It flows over 200 NA hp with bigger valves but you'll actually suffer a loss with porting. Port matching to the T-VIS and manifolds helps but enlarge the ports as little as possible !

[JekylandHyde]

From what I understand yo ushould not go over 65-70 psi on the OEM fuel lines/set up. Remember that for each psi of boost, the FPR adds one psi of FP.

I did my FPR as per this site:
http://www.trueleo.com/fpr.htm