I have a 1.8tQ and I just installed the adjustable FPR with the gauge. The gauge with the original FPR was reading approx 48 psi at idle. I thought it was 14.5 psi per 1.0 bar, and the stock FPR is 4.0 bar so it should be 58 psi. My question is, how do you get the most accurate reading on the gauge and should it be at 58 psi at idle? Or am I using the wrong calculation?

-Eric

 

http://www.furnessfluidpower.co.uk/p...rsiontable.pdf

 

Ok so I was right as far as the amount of pressure, but the main question: Is that what the psi should be at idle?

 

You need to have the vac line pulled to get a reading at idle. If you have the vac line connected you will get a lower reading, which is what you got with the 45psi.

The reading at idle will be different depending on how much vacuum the motor is making at the time. The 13psi lower at idle with the vac line on is about right if your engine is producing 20+ HGin at idle.

The 4 bar fpr is 4 bar pressure at atmos pressure. With the vac line on the FPR allows more fuel flow thru and fuel pressure is reduced, when making boost the FPR lets less fuel flow thru and the pressure goes up. The FPR is a 1:1, so the pressure goes down/up for every 1 psi of vacuum/boost.

1 HGin = .49 psi

 

Ok cool. It was on a note to disconnect the vacuum line with the kit but I don't remember seeing it that much higher when I did it. I'll try again though, makes perfect sense. Thanks for your help.

 

Class dismissed lol

 

cant beat it.. the award for greatest single source for b5 information goes to... ohhhh surprise its Mike Hood! haha

hey mike, speaking of you.. i made the decision to start piecing together a tiny BT setup.. and thru all my research ive got it all narrowed down.. will PM with specifics.. thanks man