HELP FUEL PRESSURE!!!

raininfire

Founding Member
Mar 21, 2002
96
0
17
Northern VA
Help stangers, I was going to go get my car dyno tuned, but the time and funds are not here yet. Please help me figure out what my pressure should be setup as, or atleast just a tad rich. I have and adjustable fuel press. reg. Here is my mods:
Engine: Edelbrock Upper and lower, 65mm Throttle body, 76mm C@L MAF, Cold Air.
Exhaust: Equal Length Headers, X-Pipe w/ cats, Side Exhaust
FUEL SYSTEM: 24lb injectors, MAF for 24lb, STOCK fuel pump, and AFR SET AT 29/30psi, when I floor it it goes up to about 38psi.

If i drive to dc and back from my house in vienna I am currently going through half a gallon. Thanks guys-J
 
Use the SOP meter...

Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have you buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in. Start the fuel pressure at 36 PSI, vacuum off and make a run. Turn it up to 37 and make another. Be sure to reconnect the vacuum every time you set the pressure. Keep turning up the pressure and making runs until you notice a drop off in time. If your bud was careful to record the results, you'll have a nice chart to use to find the optimum pressure.
 
I am not an expert on what your FP should be but I will tell you that mine is at 40psi at idle now. It was stock at 37psi and I just recently bumped it up to 40psi, at idle. Yours at 30 or so seems low, but you do have 24lbs injectors but I would not think that they would make that much difference. I am not sure that I was able to help you except move the message to the top of the list. :rolleyes:
Good luck :nice:
 
Hey guys thanks, the reason I know its at 30psi at idle is because I have a brand new electrical fuel pressure gauge from autometer. I am not trying to get my car to go faster per say, I want better gas mileage. This problem only started occuring after I had the 24lb injectors and maf put in, along with a new radiator, fan clutch, thermo. I do not floor it light to light. -J