It's a bit of a long story...

Last summer I had to opportunity to put my GTA on the dyno. I discovered the car was very rich and proceeded to remove fp via the regulator. I removed 22psi of fuel! We then added a couple of degrees of timing and I picked up 100lbs and 40 hp at the wheels and the air/fuel ratio was pretty much dead on. That was great! However, the fp regulator I have came on my TPIS Miniram intake. I removed that much fuel pressure that the screw came out of the regulator and I physically cannot remove any more pressure.

This leads me to my lastest problem....

This summer, about a month ago, I installed a high flow Holley fuel pump. Since then my fp, according to my guage in the car, has increased by about 6psi at idle, and remains about 6psi or so higher through the enitre rpm range until it reachs WOT. Now the fp does not change from what it was before the new pump at WOT, it's has just changed throughout the rest of the rpm range. This, of course, has caused me to run slower in the 1/4 mile! I should mention that prior to the new fuel pump my pressure was 20psi at idle, and 30psi at WOT. Now it sits at 26 or 27psi at idle and 30psi at WOT. So I am asking this...

Should I look for a new regulator that will allow me to drop the fuel pressure back to where it was? Basically is there a regulator that will allow me more adjustablilty than what came on the Miniram? Or should I send my chip back to PCMFORLESS and have them change my injector pulse width, allowing me to play with the fp with my current regulator? I would also send off my dyno sheet to help with the tune.

What should I do? Any and all help/suggestions will be greatly appreciated!

 

You should not have to lower the fuel pressure that much. I'd suggest you have teh programming reviewd, and relay as much information as possible to the tuners. If you have dyno graphs with AFRs and fuel pressure readings, that would help them immensely.

 

Thank you Vader. I agree with you and that is what I am going to do. My dyno graph does have the AFR's on them. I will send that, my chip, and as much info as I can think of and have them reveiw the tune.

 

try using a smaller injector, so you have to raise the pressure up