[INDENT]Like it says LEAN as hell in first gear when I lay into it.It is ok in other gears up to the top of 3rd.It has done this about 3 times in the past,now it does it any time i step into it hard in first only.I can't keep shootin in the dark to find out what it is.I have a t-rex boost a pump .Anyone have any suggestions.Also I want to get some 50# inj. where is a good place to buy them?Thanks for any advice

 

You have enough Fuel ?
Check the pump and connections
With 500rwhp to the wheels you should be at the limit of those injectors or beyond
Have you scanned the truck to see what the duty cycle is on them ?
I would condsider upgrading injectors and pump for your setup somthing like a 42lb at least ..try racetronix for the injectors
Do you have a Fuel Pressure guage ?does the pressure stay up ?
what pressure are you running at idle and wot ?

 

Since it's ok in 2nd and 3rd gear I don't think it's fuel pump related although at 500+rwhp you have to be pushing the limits of the stock pump.

Maybe it has to do with the PE delay setting.

 

It could still be a fueling issue. In 1st gear he is seeing a greater load than he will be in 2nd and 3rd since he is now already rolling. If you are dyno tuning and run it in the 12.5+ range in 3rd gear then on the street you can run into lean spots in 1st or after shifts and such. That's why I like to dyno AND street tune

What's your AFR on the wideband say and where are you placing the wideband?

 

F8LPONY just what i was thinking
Are you running the lm1 wideband ?

 

Yeah, that sounds right but, I'd think it would do it at the top of 3rd also. That's a lot of load pushing all that air at over 100mph with a truck.

It's probably just a fuel pump and injector at the limits issue though like these guys mentioned.

Racetronix can take care of you for both.

If you think you might use them one day go for the 57# Siemens injectors that Racetronix sells. They idle nice and are pretty easy to tune in. You have Fbody style injectors already?

 

After I posted last night, going home it did it in second, but not as bad.I tend to agree with ya'll, I think my pump is the culprit along with the inj.I'll be in touch with racetronics today . I do have the LM-1 installed drivers side ,where the cat was. I need to get a longer hose for my fuel pressure gauge, at idle it's about 43#.When it acts right it will go about 9-1 and climb to around 14-1 at the top of the gears.So I'll get a new pump and inj, and try and tune them in.My buddy that was tuning for me moved to Dallas ,so I'm kinda up the creek with out a paddle.I really appreciate the help.

 

Ok I cleaned the MAF, checked fuel pressure it's good, rises with boost.But the problem stiil exists Guess I'll get some 50 or 57# inj and go from there.

 

I am assuming you have ls1 edit, what are your ltft's? You can change the fe vs rpm tables. You should have your ltft's set from -2% to -6%. What is your log data showing?

 

Don't forget a fuel pump. Injectors aren't going to help if the pump can't supply them. At 500+rwhp the stock pump has to be getting wore out.

Talk to Racetronix on the fuel pump deal to. They can help.