Gm 6.0 or 5.3fuel pressure question.

[skipnrocks]

I have a the lt1 regulated fuel filter and fuel pump for a 6.0. My question is what is your running fuel pressure? My efi system calls for 40 psi but the programmer says he can reprogram the injectors for the higher psi so I get correct fuel. But since i can't bring my rpm up enough to read at full rpm I thought I would ask you guys that run them. I was getting just over 50 psi at idle

 

[d_daffron]

Re: Gm 6.0 or 5.3fuel pressure question.

The regulated fuel filter type fuel system does not change pressure. If it has 50psi idle, it should have 50psi wide open. If your fuel pressure drops off you have a weak pump or a restriction. In your fuel system.

 

[d_daffron]

Re: Gm 6.0 or 5.3fuel pressure question.

But to answer your question, my 2004 tahoe 5.3l Vin Z (flex fuel) engine runs about 48psi idle and 58 psi with no vacuum to the pressure regulator (wide open throttle)

 

[skipnrocks]

Is it normal for fuel pressure to raise during wot? My computer is programmed to run at 40 psi so I am running rich at 50. I was going to have it reprogrammed to accommodate the higher pressure. But I didn't know If there was a flat rate it should run at or if it would operate on a curve so I could tell them how to program the system. I really don't want to have to run a regulator at the manifold and a return line to the tank.

 

[patooyee]

It should be a flat PSI at all rpm's. If its not something is wrong.

EDIT: After re-reading your posts I'm confused. You are running a 6.0 with what regulator and fuel system? A stock 6.0 should run at 58psi.

 

[skipnrocks]

I have a tpi 350 but running a 6.0 filter/regulator and fuel pump. So mine should run 58 constant?

 

[patooyee]

The 6.0 regulator should provide 58psi constant, yes. I know little to nothing about TPI fuel pressure though.

 

[skipnrocks]

Thanks for your help guys. I finally heard back from the programmer from Affordable. He will reprogram the flow rates for me. I cant wait. This will keep me from having to run a return line front to back. He told me doubling the pressure actually quadruples the amount of fuel being delivered. So that explains the running rich with lack of power. At 58 vs 40 psi I had to be dumping close to double whats needed?! Hopefully I will have the computer waiting on me when I get back from Kansas city. Its time to wheel this thing. Other than touch up paint and wiring the winch in it is ready to rock.