Fuel Pressure

SamW · #1 (**permalink**) 02-25-2008, 03:41 AM

My GTV6 has some head work, headers, larger valves, etc. but I am still running the same old L-Jet (I have something for it in the future) but the car runs lean, I have been running the with the AFM adjusted about 12 notches for a year, and it was better than before, but could still feel the change in power as the AFR guage would move from rich to lean. Anyway, a few weeks ago DonG told me about playing with his fuel pressure regulator, said it worked pretty good. Since I already have a FP guage, I decided to give it a try. I installed a new FP regulator about a year ago, it gave me the same indicted 32 psi as my old one, so I got my old one out, measured it from tip to tip on the vacuum hose and fuel return tip and it was 87mm, out a couple of sockets on it to protect the tips, put it in the vice and got it down to 86mm, installed, now I am running 35psi at idle. Changed the AFM back to stock position and the car is running great! I need to do more road testing, but the idle is better than it has ever been (since the rebuild), I am sure this will screw with emissions, but I don't have any where I live, but I still have the new FP reg just in case!

karmat · #2 (**permalink**) 02-25-2008, 07:53 AM

Sam,

Do you have any photos? Without having a fuel pressure regulator out in front of me I'm having a hard time visualizing what you did. Sounds interesting (not for me, we have emissions) but could be good to know.

Cheers,
Karl

SamW · #3 (**permalink**) 02-25-2008, 04:19 PM

OK, this is a pic of my new one, it measures about 88.5 mm, don't go more than 1mm smaller. The way I have the caliper is the way you need to press it, drove her around today and she is running great!

karmat · #4 (**permalink**) 02-25-2008, 08:22 PM

Thanks Sam! So you literally just squeeze it in a vice length-wise. Simple and cool!

Karl