Ebay GT45 + 5.9 Magnum + E85 blow thru

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Was just searching around and some site like the supra forums say even though they are compatible with e85 the pump can prematurely fail and it's best to get a pump designed for e85 like the walbro 485. Not sure, never have done e85 convertion.
 
This latest one I bought is advertised for E85/E90. Somebody else suggested it was my placement of the pump. Too much uphill travel from the tank before it gets to the pump. Could be. Seems I never had this issue with my Walbro 255. Maybe the Walbro pulls better. Thanks again.
 
Oh maybe it is to uphill, maybe the 255 does pull harder, any chance you can install a in tank pump to help boost the fuel to your other pump?
 
Small injector CANNOT cause the fuel pressure to drop.
The injector duty cycle would max out and A/F will go lean but there'd be no drop in fuel pressure

The dropping fuel pressure is a fuel supply issue
 
True. Well either need to get another drop fuel pick and and weld it in lower and plug the higher one or see if a in tank pump can be put in.
 
Ok looked back in your thread and if your fpr is still connected by vacuum to the throttle body you need to change that. The boost reference should be coming from your carb hat directly to the fpr.
 
coreyg said:
Ok looked back in your thread and if your fpr is still connected by vacuum to the throttle body you need to change that. The boost reference should be coming from your carb hat directly to the fpr.
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There's 0 difference to the amount of boost getting to the fpr at WOT if the fpr vac line is connected to the intake, throttle body, carb hat or turbo.
Big difference out of boost, but that's not the issue.
 
myduster360 said:
There's 0 difference to the amount of boost getting to the fpr at WOT if the fpr vac line is connected to the intake, throttle body, carb hat or turbo.
Big difference out of boost, but that's not the issue.
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I'm just going off of what Bryce at fitech told me, said the reference should be coming from the carb hat.
 
coreyg said:
I'm just going off of what Bryce at fitech told me, said the reference should be coming from the carb hat.
Click to expand...

ok but think through as to why and it'll help you understand how the system is working.

Under boost there's nearly no difference. Its only at idle and cruise that there's a HUGE difference.
 
myduster360 said:
ok but think through as to why and it'll help you understand how the system is working.

Under boost there's nearly no difference. Its only at idle and cruise that there's a HUGE difference.
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I understand what your saying, I've had a few modified turbo cars (4 bangers) but this is the first tbi system I've used so don't know if there is a reason why fitech said to use the carb hat as the boost reference. Just throwing in something to try.
 
coreyg said:
Ok looked back in your thread and if your fpr is still connected by vacuum to the throttle body you need to change that. The boost reference should be coming from your carb hat directly to the fpr.
Click to expand...
Yes. Boost ref goes from carb hat to FPR, indirectly through a distro block. I've tested it, and the FPR get's boost signal no problem.
 
Fuel pressure issue is fixed. I moved the pump to the back and under the tank and replumbed my feed line. Pressure now builds and holds under boost and AFRs are more on target.

The Walbro 392 didn't have this issue 'cause it can suck a golf ball thru a garden hose but this AEM is a different animal apparently. I need to square away a few things and will start tuning and increasing boost. Shooting for 10psi with safe AFRs. Thanks again for all the suggestions guys!
 
subcom said:
Fuel pressure issue is fixed. I moved the pump to the back and under the tank and replumbed my feed line. Pressure now builds and holds under boost and AFRs are more on target.

The Walbro 392 didn't have this issue 'cause it can suck a golf ball thru a garden hose but this AEM is a different animal apparently. I need to square away a few things and will start tuning and increasing boost. Shooting for 10psi with safe AFRs. Thanks again for all the suggestions guys!
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That's good news. Keep us posted with some new track times and videos!
 
New pump mounting:
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Latest update. Ran at the track last Friday. Got 3 passes in and on all 3 the engine sounded like it was cutting out or missing really hard. My first pass was the best with a 7.30x at 92mph. I installed the 2-step firmware on the Fitech unit and wired up the 2-step to the brake light switch. I was able to foot brake it on the 2 step and get 5psi before the launch. Very promising. Car is hooking good, going straight. Unfortunately the track wasn't clocking 60 foots that night.

Fast forward a week, I discovered that the miss was actually a loose vacuum hose going to the blow off valve. The BOV was loosing pressure and flapping up/down creating the sensation that the engine was missing. I replumbed my vacuum lines from the turbo to the manual boost controller, waste gate and bov. I turned up the pressure and got it to around 10psi, peaking as high as 11.3psi and took it for a few test blasts on the street. It's running great, power feels awesome and AFRs and timing are right on the money with the Fitech. Next tnt is in 3 weeks.

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Bummer about the vaccum leak, but glad you found it those can be hard to find sometimes. Good luck at the next tnt sounds like it's all finally working out for you.
 
I also eliminated the on-board fitech fpr and blocked it off. This made all of the difference in the world with my issues at idle where it would load up or go lean momentarily and then wildly rich trying to compensate for the lean condition. Was killing off-idle performance and nearly killing the engine coming off a stop light. Details here;
FiTech EFI system
 
Thanks for the update! Glad to hear you got the FI tech working as advertised! You will be my “go to” for advice when I get mine installed on the duster. How much boost on the 7.30 run? I would think the mph would be higher but your said you had some ignition/missing issues.
Have you figured out how much power increase per pound of boost? It would be neat to find out. I’m hoping to help with that when mine is tuned more.
 
dusted said:
Thanks for the update! Glad to hear you got the FI tech working as advertised! You will be my “go to” for advice when I get mine installed on the duster. How much boost on the 7.30 run? I would think the mph would be higher but your said you had some ignition/missing issues.
Have you figured out how much power increase per pound of boost? It would be neat to find out. I’m hoping to help with that when mine is tuned more.
Click to expand...

Boost has never gone above 7psi when running off of the wastegate spring. My best ET/MPH was about 2 months ago when I was still dealing with the AFR going lean. That was a 7.2x/98MPH and a horrible 60' barely under 2 seconds.

If you want to play with the Wallace Racing calculators (and believe the results) they say my weight at ~3200 and 98 MPH in the 1/8 is 468HP. 1/8th Mile ET-MPH-HP Calculator

Can't wait to see your turbo results also. Best of luck with it.
 
Put my single plane Victor 340 intake on it after doing a gasket match. Haven't really tested yet but off-idle response seems a lot more crisp than the Air Gap.

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