When my engine was relatively stock with an AFPR, my fuel pressure was set to 40 PSI.

I have since had the engine boared over 40 (30 and a cleaning bore) installed 22LB injectors, lingenfelter runners, lingenfelter cam (will look for the specs as I don't remember them off the top of my head) edlebrock manifold, 3 angle valve job and port and polish on the heads, holley high flow fuel pump... oh and the AFPR...

At any rate, what should I set my fuel pressure too ? I am currently running at around 45, and it bogs running too lean... what pressure should I run at ?

 

anyone?

 

7 hours and you give a TTT? That's kind of sad.

When does it bog? WOT? When's the last time you replaced the fuel filter?

 

Fuel filter was replaced at the same time the pump was installed.. no more than 3 months. The bog is around 2500 - 3000 RPM. It generally only happens if I am gradual on the throttle (regular driving) . If I am at WOT, it won't do it. Also if I shift manually ( 700R4 with a ratchet shifter), it doens't do it. I know that its going lean though because I watch my A/F ratio gauge and it goes all the way lean when it happens.

 

Are you still running the stock chip with that setup? If so that's your problem. Bumping the fuel pressure 5-6psi may help keep it from spiking lean, but it's also going to make it run too rich in other areas. You really need a custom chip to take advantage of things like head porting and cam changes. They change the characteristics of the engine and that throws the factory tuning (which wasn't that good to begin with) all out of whack.

 

I have a custom chip as well.. that lt1 guy at lt1intake.com burned it for me (I think that was the guy)

 

finding somebody local to tune your car is the way to go, you need somebody there to actually see what the car is doing. Most dyno shops can do it, and probably for the same price as what you just paid the other guy. If you really want it running full performance, get it on the dyno with a wideband O2 and have the dyno shop burn you a chip from the data they get with the dyno runs.

 

unfortunately, we don't have a shop with a dyno that is that reliable. Do you think I should be running a higher fuel pressure ?

 

No, we think you should have a custom tune.

Fuel pressure is a very basic tuning tool, with a cam swap and ported heads you really should have a custom chip.