mprowe350

I finally got my car running after several set backs. It took getting a second Walbro 255 before the car started. The first never worked but made lots of noise. Now the second is installed and running strong with no noise at all.

I also spliced my fuel pressure sender into the stock fuel line near the frist dampener. The idle fuel pressure is 73lbs and under full trottle it drops to 50lbs. When the fuel gauge is at its lowest(50lbs) the boost gauge is showing 8lbs.

So far so good no detonation heard today unlike w/stock pump. Next is the SARD type R pressure regulator install. But first I will visit the Dyno next week for A/F results.

MIKE

Z1 Performance

iTrader: (564)

73 psi at idle?? Yikes

50 psi is lower than stock pressure at idle....I would definately not even bother going to the dyno until the regulator is put in.....your fuel pressure curve is going the wrong way!

Sharif@Forged

iTrader: (92)

Mike, I admire your determination to raise boost. I like it. I also bought the Walbro 255 and was going to install it without a reg for a few weeks. But decided it was not a good idea.... So I am waiting till I get my FPR.

70psi at idle is going to do nothing for you except give you a shitty idle, lots of black soot on your bumper, and a constant CEL. 50psi is actually ok for the Greddy kit at redline. Without the pump, you were probably around 38psi at redline....and you'd start running lean above 6.5psi But you need to do something about that rich idle condition.....

I agree with Z1...dont bother with the dyno just yet...in my opinion....unless you just wanna post some big peak numbers...and hide that terrible looking fuel curve.

Z1 Performance

iTrader: (564)

I would disagree about 50 psi being ok. That is less than the stock fuel pressure at idle!

Again, fuel pressure should increase 1 psi for every psi of positive manifold pressure (boost) you run - this is the only way to keep things happy for the long haul. So, assuming you run 7 psi of boost, fuel pressure at 7 psi should hit a peak of 60 psi (53 base pressure +7 psi additional), and stay there till you lift off the throttle completely - regardless of what rpm you are at.

It is so much easier getting fuel pressure where it should and concentrating on IPW/timing curves, rather than the other way around - you are constantly going to be fighting the computer.

SKiDaZZLe

i have the walbro 255 and get 75psi at idle. no check engine lights, no bad idle. car runs stioch at idle... i guess ecu can trim back stock injectors enough to make up the difference...

by the way, 75-80psi on stock injectors changes the effective flow rate from 290ish -> 380ish... obviously the car can handle this, as the PE kit comes with 380cc's and does not require an ECU flash (for stock 4psi boost).

now, if you are running 75psi on 440's or 380's (like i see in your sig)... it will probably idle like crap and run too rich...

i am going to take the 255 out soon... anyone want it? $45 shipped!!!

m

mprowe350

Idles fine, no smoke and yes I have 380 cc injectors. Feels rich through mid rpms but fast up top with no detonation. I haven't upped the boost yet I am still at 8lbs. I installed the pump to prevent detonation and it has so far. Before I couldn't boost above 5600rpms. Therefore the pump has done some good for me and the regulator willl be next. I am going to do a dyno run for the A/F results b/c some others here are running the pump and stock reg with the ATI kit. Those people are curious to see what happens before and after the regulator install. Others have had a good fuel curve without the regulator but I am just conducting some experiments for pressure readings verses A/F before and after reg install. I don't even care about HP numbers just A/F for now.

zimbo

iTrader: (4)

I love the fact that guys around here are willing to experiment and research stuff like this.

Mike, I live in Cary and would love to see your setup sometime once you get it all ironed out.

--Steve

mprowe350

Steve,
No problem I should be at CAM this week using jeffs dyno. Then the regulator will be next weekend maybe. I will let you know how things go and we should meet sometime soon.

MIKE

Sharif@Forged

iTrader: (92)

Looks like the TS Reflash and 380 injectors is helping the car run well at idle. With the Emanage and 440cc injectors, it's a total mess at idle...ask ETX.

Z1...50-52psi is stock fuel pressure at idle. Don't read too much into my post...I am not trying to describe "textbook" F/I fuel managenemnt strategy. I am just saying with with my stock fuel pump and 440cc injectors, I am very rich until about 5500rpm. Near redline, we have less than 40psi of pressure. So if I could at least get to 50psi...I would have plently of pressure and duty-cycle left to get to 11.5:1 at 8psi or so...maybe more....nobody has eperimented with this yet on the 440cc injectors.

My first step is to istall the FPR and return without running a vaccum line. If I can maintain 50-52 psi or pressure across the board, and still maintain 11.5:1, then I am leaving it alone. I am 95% sure this will work.

zimbo

iTrader: (4)

What day are you going to be over at Jeff's? I've done a lot of "stuff" to the car since my last dyno over there and I've been meaning to head over there sometime. PM me if you know what day and don't mind a bit of company.

--Steve

derek_i

I can't believe someone actually posted this here. You, sir, deserve an award.

HP numbers are good on paper, A/F numbers keep your car on the road.

-D

mprowe350

EXACTLY!

mprowe350

Steve,
I will PM you tom or the day after with a possible date and time. I am going to call Jeff and arrange something for early evening one day this week. I have read alot of your posts and would love to see your car. I will only make one or two pulls so I am very quick.

MIKE