Josh

iTrader: (9)

What is the most accurate way to compare the fuel pressure rating (at the rail) of an aftermarket fuel system with the stock pressure rating? In other words, how is the stock fuel pressure rating of 58 PSI obtained? With the pump primed (engine off)? While the car is idling? At WOT?

Thanks,
Josh

WS6FirebirdTA00

iTrader: (33)

turn the car and and put a fuel pressure gauge on the schrader valve and see what she says

72ChevelleConv.LS1

iTrader: (5)

You should have 58 lbs when you turn the key to the on position and when at idle. I think if you have a real good supply system, IE big pump and big lines you will see less drop on your system than if it is stock. at WOT.

redmist

It should be 58 all the time, if not you have a weakness in the system. You should measure it as close to the fuel rails as possible.

WS6FirebirdTA00

iTrader: (33)

i get 62 psi at idle with a 255 pump

Josh

iTrader: (9)

I installed a Ractronix kit a few months ago, but when I put the pressure gauge on the fuel rail it bounces around so quickly I can't even read it.

Josh

WS6FirebirdTA00

iTrader: (33)

then you prob have that line in the tank too loose. the flex hose that you have to tighten with a hose clamp that is. if its too loose or you have a leak elsewhere, then the gauge will go back and forth and sweep about 4 psi range, looks likes its vibrating

slow

iTrader: (7)

LS1 f-cars run a static rail pressure, so idle, wot, and part throttle should be 58 psi at the rails.

Ryan

V8_DSM_V8again

I like to run a electronic fuel pressure gauge on forced induction FI cars...

I own a shrader valve type diagnostic gauge but I sure feel better seeing beign able to see that the pressure goes up the same # of PSI as my boost gauge..

WS6FirebirdTA00

iTrader: (33)

those damn things cost so much though thats what i hate about those gauges

V8_DSM_V8again

Cost alot less than a forged short block should you have a pump failure/weakening pump and lean out at 30+ psi...

WS6FirebirdTA00

iTrader: (33)

i agree, still hate that they are so much though

92CamaroReallySlow

I bought a nice diagnostic guage from Murrys. It was 40 bucks but it was worth it for me, even had a little purge. Its also nice because I have an adjustble FPR so I just hooked it up, set it to 58 psi, and I was done.

V8_DSM_V8again

Think fast


I saw NOS under hood mecanical for 15.99 with 46min left...

Some decent prices on electronic ones too..

Those with a cowl induction hood know what to do with a mechanical...