Need help with an FI WOT lean spike in HPT
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You know I thought about fuel pressure yesterday, figured there was to many variables in the tune to warrant an FP test, I was wrong.
Hooked the FP tester up and it read 35psi at idle, a quick rap of the throttle in idle showed 25ish psi. So I guess that explains the problem. The tank is a Spectre performance EFI tank for A-bodies, it has a Delco EP381 pump internal which is stock in Vortec 454 trucks. There where some guys on tech that did the calculations and figured it was good to about 450bhp, guess that was wrong. I guess a Bosch 044 is going inline this week.
Thanks for the help.
Hooked the FP tester up and it read 35psi at idle, a quick rap of the throttle in idle showed 25ish psi. So I guess that explains the problem. The tank is a Spectre performance EFI tank for A-bodies, it has a Delco EP381 pump internal which is stock in Vortec 454 trucks. There where some guys on tech that did the calculations and figured it was good to about 450bhp, guess that was wrong. I guess a Bosch 044 is going inline this week.
Thanks for the help.
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Ok guys, This has got me thinking now. The dual channel wideband indicated #1 bank was rich. At 14.7 on channel /bank 2, bank 1 was 14.2ish I wonder if I have a stuck open injector in bank 1 causing a pressure bleed and low FP. When I cranked the car the pressure went up to 35psi and dropped to zero as soon as the pump stopped priming.
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FPR, check that fugger. Make sure the gasket is intact. I wouldn't guess that one is stuck open, you are showing 14.2 at stable driving, a stuck open injector would be more problematic IMO. Pull the plugs on bank 1. See if one of them is waaay nastier than the others. If so, then I'd go with an inj prob, otherwise...it is very odd you don't get some pressure held. Hmmm, I would guess if the fpr is shot or screwing up it could thoeretically let pressure bleed back to the tank as well.
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I could change it, its brand new from magnacharger but they arn't that much so i guess I'll change it out and see what happens. What would explain one bank running richer than the other at cruise/part throttle?
#15
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I wasn't aware that maggy supplies the fpr. The inj's are from maggy as well? If they aren't and they aren't flow matched, it is quiet believable that you have a 5% difference in banks. Is this kit new?
I guess an inj could be stuck open, it just seems to me you'd have a richer scenario. Pull the plugs.
I guess an inj could be stuck open, it just seems to me you'd have a richer scenario. Pull the plugs.
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Fixed the issue, it was the regulator. Holds steady PE AFR at all boost levels in all gears.
And holy crap this thing flies!
Your right, it did not come with the reg, I had to swap it in. I am going to do the IFR calcs and see what happens.
And holy crap this thing flies!
Your right, it did not come with the reg, I had to swap it in. I am going to do the IFR calcs and see what happens.
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Per dewmanshu's request, here is a quick video:
http://vids.myspace.com/index.cfm?fu...deoid=56296008
45-95mph in 7 1/2 seconds anyone?
AFR is set a little rich right now at 10.6:1, IATs where 135*, 17.5* timing, just a tick under 5psi on the boost gauge, only registered 88% TPS.
http://vids.myspace.com/index.cfm?fu...deoid=56296008
45-95mph in 7 1/2 seconds anyone?
AFR is set a little rich right now at 10.6:1, IATs where 135*, 17.5* timing, just a tick under 5psi on the boost gauge, only registered 88% TPS.
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