No chip or anything its all stock 93 computer stuff. Think the pro-m 83 can only go to 440rwhp? I would think it could do more than that. Half the people I talk to say pump is the problem and the other half say injectors are to small. Going down the road and getting on it I don't see the FP drop any. I know its one of the two just don't want to buy both if only one is the problem.
93 LX
R331/AFR 205/Vic 5.0/? psi
i made 460 with a proM 75mm bullit(plastic) it was at 4.7 volts that was with about 11lbs of boost from a novi 1000......my buds car made 460 with the same MAF but he was running 14lbs from a s trim and he was 4.98 volts
we both use 38# injectors
how much boost are you running?
what i would do is hook up a DIGITAL volt meter to the maf....get a friend...go for a ride....HANG on....and mash the pedal wide open throttle in 3rd or 4th gear...have your buddy read the DIGITAL meter.....then have him change is underwear!
Mike
Originally Posted by Forcedpower
Last edited by MikeyMustang; 06-05-2004 at 06:00 AM.
YOU NEED FP!!!!!
Did you turn it up to 50 psi then work it down?
See my sig? I have a little ProM too, the chrome one, and a GSS340.
SOLD!!!! 442.3 rwhp 421.2 ftlbs @ 10 psi SAE
87 Mustang GT
306, 10-1 comp., B303, J&P ported 6037's, ported fake Ebrock intake, 65mm tb, 70mm egr, 3.73, 1.7 RR's, Pro-M 75 S/C calibration, 42lb injectors, B&M RIPPER, BBK LT's, RACE MAGNUMS w/offroad! and Pretty blue TAYLOR's!
308.1 rwhp 327.6 rwtq -N/A
OK.......you need some feedback from the engine on whats going on. Do you have a fuel pressure gauge you can read from the car? if not can you rig one up for testing? If you have 42psi of fuel and 10 psi of boost, if your regulator is working correctly you should have 52psi. I have a FP gauge on the cowl for two reasons.
1. If the fuel pump "gives up" you can see it in an instant. Cause when they do they usually drop to 30 or so till you let off.
2. Easy to set Fuel pressure with nothing to unhook when your done adjusting.
MAF voltage is very important also. If the the fuel system "gives up" electricly, then it dosen't matter if you have a Weldon pump with 96# injectors, your not gonna have enoung fuel.
Try the few things that have been mentioned and see what happens.
IMHO i don't think you need more pressure, i think you've got a thorn in your side and when you pull it out you'll have one bad machine! ;)
GOOD LUCK!
Last edited by regattacoupe; 06-05-2004 at 11:29 AM.
89 Coupe with parts stacked inside of it and about 30#'s of dust on it with no end in sight. :weird:
Although I am collecting parts for a 12.5:1 393 :D
No he doesn't. FP is not the problem here. Either the pump is not up to the task (which is a fuel volume problem) or the MAF is maxing out. 42 psi of fuel pressure is plenty for a set of 42's. He shouldn't even be close to maxing them out...especially @ only 440 rwhp. I run a single GSS340, stock everything lines and rails wise and although I have yet to dyno it, I know for a fact I'm over 440 rwhp. My FP is at 40 psi vacuum off and I don't run out of fuel. My A/F is a rock solid 12:1 all the way to 6000 rpm and my duty cycle on the injectors is 75%...plenty safe.
Just a thought...make sure the fuel filter is clean...you'd be amazed how something as simple as that could cause a problem like this.
Rain is killing me. Anyway I moved my fuel up to 50 took the car for a drive and watched fuel pressure it went to 58-59 under full boost. Rule out the pump? Could really tell if it was any more power or anything.
Can someone tell me how to measure the voltage on the mass air? What wires?
93 LX
R331/AFR 205/Vic 5.0/? psi
how was the a/f????
According to the Pro-M tech section:
Pin B = ground negative
Pin D = output +
87gtNOS I don't have anyway to tell a/f other than the dyno.
Thanks TheHawk05 I'll be trying that next.
So my pump doesn't seem to be the problem and if my mass checks out then it can only be the injectors right? Or will turning the fuel pressure up really bring my a/f from 14.? back down to 12? Even then if I have to turn the fp up so high doesn't that mean the injectors are to small?
93 LX
R331/AFR 205/Vic 5.0/? psi
No...the 42's are not too small. They won't even be working anywhere near their limit @ 440 rwhp. I'm still going with an out of whack MAF or fuel system problem. You can see it in your dyno graph. Normally when you run out of fuel due to small injectors the graph for the A/F doesn't rise like yours did. Yours is all fine and dandy until 5200 and then it heads for the sky in a real hurry. Most dyno graphs I've seen where injectors are too small there is a progression in the A/F curve until the injectors go static at which point the A/F curve will instantly spike very sharply.
And cranking the fuel pressure up won't bring your A/F from 14:1 back down to 12:1.....2 points in your A/F is a huge jump.
Quick question: How much boost do you run and who's 42 lb injectors are you using (Bosch, Lucas, etc)
I see 9-10psi of boost and have bosch 42 with the lime green top.
What could it be in the fuel system? The regulator is working b/c fuel goes up with boost. If the fuel pressure isn't dropping under boost isn't the pump ok? Or not enough volume?
93 LX
R331/AFR 205/Vic 5.0/? psi
Pro-m site says the 83mm is good for 900hp. If thats right how am I pegging it? Sorry really don't understand.
93 LX
R331/AFR 205/Vic 5.0/? psi
If the fuel pressure isn't dropping at boost where it's going lean(and you verified this) then it's not a pump problem. This has to be electrical. The Pro-m site tells you that HP rating to let you know that past that power level the meter is a restriction.
89 Coupe with parts stacked inside of it and about 30#'s of dust on it with no end in sight. :weird:
Although I am collecting parts for a 12.5:1 393 :D
So if it is the meter than how do I fix it? With a chip or PMS?
93 LX
R331/AFR 205/Vic 5.0/? psi
He hasn't verified this. Eariler he mentions his fuel pressure only goes up a couple of pounds. Fuel pressure regulators work at a 1:1 ratio when seeing boost. If he is seeing 9-10 psi of boost, his fuel pressure should be at 51-52 psi when he does hit that boost level with a base fuel pressure setting of 42psi vacuum off. If it's only going up a couple pounds, he has a problem with his fuel system.
The MAF size is not a problem as 83mm is plenty big but it wouldn't be the first time Pro-M screwed up a MAF and had calibrated it wrong and had it hitting max voltage too early. You can determine if a maxed out MAF voltage is causing this problem by hooking up a volt meter to the leads mentioned eariler and go for a drive with a friend and floor it up to 5200 rpm (just before you know where it went lean on the dyno) and have your friend tell you what the voltage was. If the MAF is not right you 'll have to send it back to Pro-M
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