whats everyones f.p. at??


New Member
Nov 7, 2003
dallas tx.
well ive been trying to fix this slight bucking an poping... i know its a lean condition since it pops through the intake... ive tried a new mam an nothing... so i increased pressure an bam it fixed the high end prob, but low end now suffers... if i run it at 40 with vacuum off it only does it slightly... any higher an theres no prob... but at idle with the vacuum on ive seen my pressure seep up sum when my car starts to surge... (freakin e303)
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38-40 is normal... popping through the intake is usually a MAF issue. Pro-M could never really get the curve perfect with the 75mm bullet and a 24# calibration.
The curve on a 19#,30#, 36# were all the same. for some reason the 24# had a slight issue...atleast that how it was. You will find a lot of guys that have some issues with the car rich down low, lean up top.

Remember adding FP with the regualtor only gives you the extra pressure at WOT, at idle and below 70% throttle the O2's and ECU will make it what what the Factory settings is for the A/F ratio. The ECU is adaptative....it learns as you mkae changes.

If you need more fuel down low you need a larger injector.

I had the same issue on my car with a 75mm Pro-M and 24# injectors, however my buddy uses my meter on his car with no issues...it's hit or miss. I went to a C&L 76mm and it went away with 24# and 30#, and went to a 80mm Pro-M with a 30# and it ran even better.
Ok I was having the same problem. My fuel psi was at 35 with vacuum off. any higher and the car would not idle for crap but it would run better at higher rpm's. I had a sense my ignition wasn't up to par. plugs,wire and cap and rotor had a very small improvement. So I put a performance distributors, high ouput coil and ignition module in. Wow set my fuel psi at 45 with vacuum off because I did a thread and that's the psi most everyone told me to try. Even with the stock engine. No problems and the car has more power that it ever has. My engine is all stock except cai, and hi flow exhaust. Just a thought about what fixed mine.