Totally stumped?????

[nastynavy]

My set up is a stock motor with a PT 54, CAS front mount, 50 lb injectors, 9/11 3200 stall, 3" downpipe with 3" exhaust with Ultra Flow bullit muffler, stock gears, stock heads, stock cam, stock intake and throttle body/plenum, with upgraded valve springs from the old Modern Muscle. My problem is the car just doesn't move like it should. It feels decent but it doesn't really go anywhere. I ran a 13.3 with this setup: Joe Lubrant race chip, 114 octane fuel, 21 lbs of boost with virtually no knock but not running rich. I ran 12.78 on about 19 lbs of boost with a 51 turbo and the stock intercooler with my boost going all over the place because of my ATR downpipe (problem was solved before I ran again). I am just tired of trying to figure it out. I am thinking maybe the cam is worn but I don't know how you would tell that. Any suggestions would be very helpful. I have also done the regular stuff like a fuel pump, k&n filter, fp regulator, volt booster, maf pipe, new O2 sensor. Thanks in advance for any advice and help you offer. The car has just turned 100,000 miles also if that helps anything.

Josh

 

[John Larkin]

You and I have a real similar combo. I am going to the track very soon and was given this advice: Crank up the boost. Apparently, the 54 or whatever larger turbo you use really doesn't see the sweet spot until above 22 psi or so, especially with unported heads which I have and so do you. My plan is to use VP16 and crank it up. If you have an EGT, I'm also told to start at about 1450° and check plugs, then work your way up with no knock. The first two trips to the track will probably be time consuming but a steady increase in safe performance should be the result. That and a high boost launch should help. Good luck to both of us.

 

[Berman]

Something is definately wrong. Your car should be way faster than that. Have you done a compression test? Your motor could be really tired. Checked your intake manifold for leaks at the gasket? Do you still have stock headgaskets?

I hope you get it sorted out.

 

[scgnx]

My GN was the same way, it wasn't responding to the bolt-ons stuff like it should. I was stuck in the low 13's forever. Until I change my Timing chain & gears. The original timing set was off from the factory. The timing marks would not line up and was off
by almost 1 tooth. Installed the new set and bumped the crank to line the marks up. Now its the beast it should be. Ran a 12.02 @113 which was my first 12 second pass!!