[leeroy_25]

I am building an RB30 motor and hoping for around 500-600BHP gross.

I was thinking I needed an adjustable FPR of some sort but I seem to remember getting told a while ago that the stock one would be ample?? I am running an aftermarket pump of course..

Thoughts please.

Thank you
Lee

 

[Chris Wilson]

The FPR only RETURNS excess fuel to the tank. The only need for a bigger flowing one is if you have such excess fuel pump volume, at say idle, that the stock one can't return fuel fast enough, and fuel pressure builds to above the blow off spring pressure in the valve. An adjustable one may help with a mappable ecu if you want to run injectors at a higher or lower line pressure than the stock regulator supplies. Probably in 95% of cases a stock regulator is fine.

 

[leeroy_25]

Thank you for that sir! I remember the FPR is on the return side. Now I have just twigged exaclty why that is! As well as helping to keep a constant pressure accross all the injectors easier as well I guess?