Been trying to figure this out, ever since I changed to the 255 pumps (it may be before but never noticed) I see about 32psi @ idle and about 58psi @ WOT that seems fine to me. The problem is before boost the fuel pressure goes to 40psi then drops to 32psi and goes up and down. It seems fine in boost but not sure if the hoses are loose on the pump. Changed the fuel filter already. Want to know what you think before I drop the tank.

 

Will let everyone know what I find. Going under the L to drop the tank now.

 

When I first installed my pumps one of the hoses came loose and I had to drop the tank to replace.

 

Well I did not find any hoses off. I did replace all the ford clamps to be sure. Looking at pictures to make sure all my vac. lines are correct.

 

seems weird to me cause mines pretty steady throught out all the RPM's. I see aroundd 35psi at idle and 50 psi max with my gauges.

do you think maybe it could be the gauge? is it electric or mechanical? I could see electric doing stupid crap like that.

 

If it is when you are just starting to see boost it could be the the computer bypassing the dropping resistor for an instant and then putting it back in the circuit.The computer is on the fence so to speak.Because the bigger pumps have more cap. the psi regulator can not compensate for the added fuel.Stan

 

Mine is steady unless it is just in boost then it goes funny. I think it my be something like Ruslow is saying. The gauge is electric.

On another note, I have IT24 plugs in, the 255 pumps and 18# boost and my L runs nice and safe on the stock program. (running 94)

The funny thing is my L runs 13.5deg timing stock, I was told that 16 is more common. But with a chip my L runs more timing than it does in someone elses.

 

I know this is an old post, but this is the same problem I am having. What is the sollution for the problem?

 

I see 30 psi at idle and 50 psi at WOT... Without a boost a pump or regulator I have never seen 58 psi on a lightning...

 

Casey did you just install fuel pumps? Make sure they aren't to low in the tank and starving for fuel!

 

How is that possible. They sit in a holder with a bottom resting point to it.



My issue is the part throttle lean condition till the high speed relay kicks on then all is fine.

 

Give me a call and I will help you out.

609-567-5774

 

Why don't you help the people that are having problems with your built motors? This ***** is getting really old with you Tom. Just make right like you said you would in the first place.