View Single Post
911st 911st is offline
Registered User
Join Date: Jan 2004
Location: Sacramento
Posts: 7,269
My guess is the stock FPR is a 1/1. That is for every lb manifold pressure varies, fuel pressure changes. This is pretty typical. Thus, w 7 lbs of boost, fuel pressure should increase about 7 lbs.

Thus, I think we are about a 2.5 bar 1/1. I think there Bosch FPR up to 5 bar and some that are 2/1 for a 2 psi increase per 1 lb change in manifold pressure. It has been a while sense I looked into this.

However, this is not enough to keep the stock injectors with turbo as they are not far from there limit on the stock motor unless fuel pressure is raised more than 1/1 as with Rising Rate FPR.

As we can see the factory FPR increases it's rate with boost. Thus, it should not be an issue if we use a FPR that increases at a factor of more than 1/1 as long as it is dependable and stable. It helps to over come some of the idle quality that comes with larger injectors, might save the cost of new injectors.

I guess the concern being we do not go so high on the FP that we create other issues.

The Bell RRFPR is the standard but again, we might want to look into the Synpase adjustable RRFPR.
Old 05-06-2010, 01:41 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #30 (permalink)