Fuel Pressure Spike, but going lean

[DanielB]

Just installed the budget Lethal Performance return style fuel setup. My base pressure is set at 40psi, then when you floor it the fuel pressure steadily climbs. At 4800RPM the car spikes to 75psi and leans WAAY out then the car shuts down. My alternator seems to be fine also.

Anyone have any idea?

 

[black03]

Just installed the budget Lethal Performance return style fuel setup. My base pressure is set at 40psi, then when you floor it the fuel pressure steadily climbs. At 4800RPM the car spikes to 75psi and leans WAAY out then the car shuts down. My alternator seems to be fine also.

Anyone have any idea?

How many psi of boost are you pullied for and where are you reading the fuel pressure from?

Your fuel pressure should go up 1psi for every 1 psi of boost you are making. So if you run a 40psi base pressure and you're running 20psi of boost the peak pressure should be at 60psi. For you to be getting 75psi fuel pressure doesn't seem to be right unless you're running 35psi or you're getting an incorrect reading. Also to lean out with 75psi doesn't make sense as well unless you're out of injector. If pressure is there and the injectors are keeping up with the demand you shouldn't lean out. That takes us to the next question of what is your A/F and how are you getting that reading? Tailpipe sniffer or is the sensor installed in one of the bungs on your midpipe? Who's tuning the car?

Once you give me a little more info I can help you better.

Thanks, Jared

 

[DanielB]

My car has a 2.3 Whipple, with a 3.0 upper and a stock lower with Kooks LTs. For fuel I have the budget return setup with 60lb injectors and a SCT2400 Maf. Its doing 18lbs I believe. The tuner said that the car was at 11.6:1 A/F all the way up to 4800RPM when it shuts down and the A/F goes to something like 15:1. The base fuel pressure is 40PSI. I'm not sure where he was getting the reading, I'm pretty sure from the tailpipes.

I believe he is reading the Fuel Pressure from my Autometer gauge inside the car. I'm trying to get the data log from him so I can post up and have a better understanding of what is going on.

 

[black03]

My car has a 2.3 Whipple, with a 3.0 upper and a stock lower with Kooks LTs. For fuel I have the budget return setup with 60lb injectors and a SCT2400 Maf. Its doing 18lbs I believe. The tuner said that the car was at 11.6:1 A/F all the way up to 4800RPM when it shuts down and the A/F goes to something like 15:1. The base fuel pressure is 40PSI. I'm not sure where he was getting the reading, I'm pretty sure from the tailpipes.

I believe he is reading the Fuel Pressure from my Autometer gauge inside the car. I'm trying to get the data log from him so I can post up and have a better understanding of what is going on.

Based on your mods you should be making around the 600rwhp range which the budget system and 60lb injectors can easily support. The air/fuel looks great before your issue occurs. I'd try and get a little more info from the tuner though. Did he make sure both pumps are running? What did he mean by shutting down? The car simply dies at 4800rpms or does it slowly go lean. Who is the tuner again?

We definitely need more info in order to help you trouble shoot what the issue could be.

Thanks, Jared

 

[DanielB]

Can you PM me your email so I can send you the data log file?

 

[coketo]

was this issue fix? am really interested in the KIT but would like to know if it works, thanks

 

[black03]

was this issue fix? am really interested in the KIT but would like to know if it works, thanks

The budget systems are track proven and work excellent.

We've got customers running 9's making well into the 700+rwhp range with no issues at all.

Not sure what this customers issue was but we never heard back from him so I assume whatever was wrong has already been fixed. My guess would be a tuning issue.

Let us know if you have any other questions.

Thanks, Jared

 

[redfr03svtsnake]

Maybe a spike from spark blowout or bad cop....?