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Ever since I switched to return style fuel rails and went to -8 feed, a/f is good but it just feels like there's somethin holdin it back now. I'm boosting the stock FPR that's on the rail. I've also eliminated the silver canister in the tank that has the stock FPR on it for returnless style. Does it just need to be retuned or could there be something else?
do you have a fuel pressure gauge on it? What is the pressure running? Hopefully you do so you can see what is going on since you've tampered with the fuel pressure regulator. Too much pressure and it will be running rich at startup and pulling a lot of fuel in the tune when in closed loop. Too little fuel pressure and just the opposite.
I see. No I don't have one, I'm only relying on wideband. I'm wondering what would happen if I plugged the FPR off.
Its really hard to tune a truck if you don't know what your fuel pressure is doing. It could be 58 psi at idle when you have lower voltage and jump to 70 psi when the engine rpm comes up the the fuel pump gets more voltage. the FPR is there for a reason and that is just one of them.
So that's probably why it felt so snappy before, even though I was running out of fuel up top, fuel pressure was slowly dropping when I hit the throttle. Right? I had a gauge on there for a little wile before I went return style and it was like 60 psi then dropped all the way down to 45-50 psi.
Have you gotten any fixes on this yet? Im having a dilemma about an intake swap because I have a deadhead/returnless type setup and need to go return style.
The injector tables are different for a non-referenced vs referenced FPR. The referenced FPR will have a straight flat line graph in the table since it keeps the pressure the same when the vac changes. A non-referenced table will have values that change related to the engine vac.
If yours isn't set correctly you will have fueling problems.
I see people using the vette regulators a lot with no correction in the tune, not a good idea.