First a little background. My car is a very low thirteen second car, that has run a best of 13.2 (twice), with numerous 13.3,13.4,1.5, etc. These runs were done with the cc304, Moroso CAI, headers, catback, panhard/LCA/SFC, and at the time I had 3.73. My best run on 4/10/02 was:
R/T: .826
60': 1.990
330: 5.577
1/8: 8.541
MPH: 83.74
1000: 11.092
1/4: 13.228
MPH: 104.91

My second best run and second best MPH was on 5/15/03, and looks like:
R/T: .717
60': 2.156
330: 5.736
1/8: 8.676
MPH: 82.94
1000: 11.192
1/4: 13.292
MPH: 108.80

Now on to why I want to blow my car up. I went to the track on 5/27/03 and the BEST run and MPH of the night was:

R/T: .652
60': 2.062
330: 6.070
1/8: 9.279
MPH: 76.74
1000: 12.045
1/4: 14.348
MPH: 101.33

The car seemed to be running strong but wasn't the case. This was the best run out of SIX . The car was struggling to hit 9.3-9.4 @ 75-76 in the 1/8 and did not want to go any faster than 14.5-14.9 @ a lousy 96-97 In fact I ran a 95 Impala that ran a 14.3 @ 97.52 to my 14.732 @96.87 and we both had similiar launches.
The car since the low thirteen has everything in the sig. The car now has 3.45 but is still programed for the 3.73, but I don't see that as a huge problem. When I got home I took my fuel pressure because these were the first run with the Walbro 255 and new fuel filter. At idle it is 39-40psi and 45psi without the vac. line on the FPR. When I rev the motor with the vac. line connected it drops to 35 psi, but returns to ~40psi as the motor revs. Is that right? Is my FPR bad. Do I have a blown head gasket?
I tried runnig the stock ignition but that was of no help. Could it be a burnt wire, bad plugs, opti? The car does have a slight miss/back fire if it is reved too quickly when it is in P, but that is a hit or miss thing. I had gone to the track with everything but the walbro and the car was stumbbling out of the hole and the best launch I had was a 2.4 but the car was still going 13.5-13.7 @ 104-106. ALL my runs ever have been at the same track with the same tires, with roughly the same weather conditions. The plugs and wires have ~10k, and the CAI has a brand new replacement air filter. I need help or any suggestions, or the car gets it.

 

Its either the fuel pump or fuel regulator.

I had the same problem with my stock pump.

I'm having a problem withe the regulator now.

 

Thanks for the reply. I think my problem is the fuel pressure regulator because the new walbro 255 has less than a 100 miles. How much is a fuel pressure regulator? What is the part # for a stock OEM regulator? I am going to do a compresion test on the car here soon, but any help or suggestions is GREATLY appreciated. HElP my car is slower than new GTs . LOL

 

I checked the local parts store and a stock one was only $20 less than a Holley adjustable one from Summit. Thats the one I got