SICAMG

My fuel pressure is around 75psi .....is this a normal reading? I am used to american cars being around 45-50psi. Thanks

shardul

iTrader: (1)

Mine is 80 to 82 psi at idle and drops to 65 at WOT

SICAMG

Thanks Shardul! Since I took out the factory fuel filter in the tank I noticed it to be alittle higher so just wanted to make sure. By the way my Xentry is now working perfect! Thanks so much!! your IT guy is fantastic as well.

shardul

iTrader: (1)

welcome sir!

ben73

I am taking my 05 to the track this week and thought it was worth checking the fuel system first.
I found that mine also drops to about 68psi under load.
Has this been determined to be normal for these cars?
If anything I expected the pressure to be boost referenced and increase under load.
I guess I should hook up my WBo2, as that's what really matters


Thoughts?

BoostedAero

This is a returnless system, pressure at the rail is determined by a few factors.

*Pump Health, healthier pumps = more stable fuel pressure and
ability to keep up.
*Cleanliness of the fuel filter, drawing against a clogged filter gives you a lower starting pressure and lower overall pressure at the rail which will leave you running into a lean condition above 3k rpms

*Injector Size, larger injector = larger amount of fuel used in the rail
= lower pressure under WOT
Injector size doesnt really cause too much of a change with a healthy system so long as you are not trying to push the limits and run E85 or something crazy on the factory lines/pumps.

My minty fresh fuel system yeilded 80-82psi at idle and cruising while underload WOT I see 68-72PSI at the rail. This is with a new factory fuel system +60lb/hr (630cc) injectors.

ben73

Thank you, this tells me that this pressure drop is normal for these cars.
I installed my WBo2 today and happy to report that it shows in the low 11 range to the top of 2nd gear, so it appears to be getting enough fuel