N1 Andy

So...I went to the dyno today, with Dave Lee, well respected local tuner. It was going well basically until the car started making 275 or so hp, the car started going lean around 6600 rpm's.

So after 5 hours on the dyno, 2 walbro pumps, a brand new fuel filter, 2 regulators and even trying massive duty cycle on the injectors, we gave up. Very frustrating, I'm tearing my hair out over this.

It can't be anything software wise, it has to be an electrical or mechanical issue.

Possibilities!?
-Injectors are bad? don't see how, precision 880's with 2000miles on them.
-Power supply weak to pump? didnt think stock wiring was an issue until closer to 500whp
-Regulator? Rail psi was at 45psi at one point and we watched it climb as boost came on, seems to be doing its job fine.
-Resistor box issues? 99% positive I have the wiring right.
-Clogged hard fuel lines? doubt it, but maybe?!

Setup is as follows:
Walboro 255
Precision 880's
Generic FPR
Innovative GT61s
Shitbird Manifold
Chingagate 38mm
Perrin MBC

Could you guys throw out some suggestions that I could try? because I have NO idea anymore.

Peeonu25

dave lee knows his ****, im suprised he didnt figure it out.

if youre fuel rail is getting good psi, theres only one last thing from your rail to the cylinders and thats your injectors. a faulty injector isnt that uncommon thats where id start.

pull out the noid light, ohms light... unless you have a flow tester for injectors you can always pull the rail and crank it over.

Peeonu25

oh... i also hate christine... the one im talking about is from ballard, i dont think it's the same one.

pettyboy69

iTrader: (2)

maybe there was something in the fuel and lines that broke up and is clogging the injectors filters? i know its a long shot but you have tried just bout everything also depending on where the injectors came from they might have gotten stuff in them from the car they came out of

good luck man

i had the same problem with mine but it was cuz i bought 880's and they shipped me 745cc injectors and the only way i found out was tuning tuning tuning and then finally i double checked the part number on the side of the injectors and thats when i figured it out

also maybe try double checking to make sure they are high or low impeidence

Turbo-LS

iTrader: (4)

even if they shipped him 745's thats still more than enough injector at that power level. you have a clog somewhere i would say and your not getting the volume or fuel that you need. sounds like a clogged injector or fuel filter or just bad injectors

pettyboy69

iTrader: (2)

thats true 745 is more than enough for over 250whp

Turbo-LS

iTrader: (4)

745 is good for 400 range easy

N1 Andy

From what I've seen, upgraded wiring is NOT needed until 400+. That is only from what i've seen though. They are 880's for sure, we ran the part number. And ive never seen high impedance 880's, they are low.

The only thing that bothers me is the fact that I relocated the battery and did a wire tuck and the possibilities of some wiring getting wacked out and improper sized is great. I think I will run new -8 from pump output to rail with 2 banjo's on it, and run a relay and 10guage wire to the pump directly from the battery just to eliminate all possiblities for problems, and get the injectors flow tested.

N1 Andy

I'm talking about the Governor lol, but if the one from Ballard's name is Christine, I probably hate her too.

Peeonu25

im with these guys, clogged injector or something, just grab an ohms tester, check the resistance etc for the wiring and if they all come out good, give presicion a call and tell them you have a faulty injector.

yeah shes one to stay clear of.

agreed. this time last year i was at chicago o'hare for load master training for airline SAS, ended up next to our old gov gary lock on the flight home. talked to that guy for 3 hours, definitly miss him as our gov.

N1 Andy

Locke was a good man, Rossi probably would have been a good man too. Gregoire is just a piece of ****.

locash

Have someone watch the fuel pressure gauge when making a pull to see if pressure is dropping up top.. That will at least narrow down the issue..

Peeonu25

Did you read the post?

Peeonu25

I'll be home on the 20th/21st, if you havnt gotten your injectors flow tested by then or if you havn't solved your problem. i have 4 in the box precision 680s for my h22 that ill let you swap in to see if thats the issue.

inspector01

That happened to me, precision 880s that I used for about 2000 miles, one took a complete ****, I had to send them to precision, they flowed them, one was bad, they charged me for flowing the injectors and a new injector. $180 to get a working set of injectors back.

HiProfile

Are you still using the stock fuel dampener? It's the white-ish bulb thing onthe pass. side of the fuel rail. Occationally they take a crap, and for some reason do stuff similar to this. It's usually only after a certain power or RPM.

extralargenog

iTrader: (1)

Glad I could help with figuring it out Andy.... Knew it wasnt the majic timing oogie boogie thing JD was trying to sell us on.... Made perfect sense when I thought about it and came up with what I thought was the issue... Just glad it was so simple...

Not some overly complicateted and totally left field ignition issue... The inlet to the fuel rail was hollow on the end... and it had a fuel dampener with the correct crush washer with the cutouts for the fuel to flow around (like this):



What the fitting DIDNT have was a pair of holes drilled perpendicular to the inlet barb that is located inside the banjo (the one in the barb that feeds the rail that the banjo goes over) drilled a hole in that ****er and took the revlimiter off of it to see whnat happened to AFs. They dove into the 9s at 9 PSI all the way out to 9k at 9PSI.

Soooooooo


We need to get that thing tuned :O) SOON... Hit me up when you gots some time!


SpikE