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RACE5
08-15-2011, 09:15 AM
Here's the details:

Car runs great down the straight. Lift and rotate into the corner and then when you pick the gas back up the engine stumbles. It tends to get more pronounced as the race goes on and it doesn't matter if I let completely off the gas or if I just breathe it a little on entry. When the stumble happens, the car pushes and then my corner is toast, especially in the slick.

Now, the car wants to stall when coming off the track, seems to be loaded up wit fuel (you have to crack open the thottle to start it). Sat night, stumbled so bad it stalled the car in the heat (running 2nd with 6 more behind us "pretty scarey"!

We have replaced the carb, msd box, coil, coil wire, ignition switch, cleaned the fuel filter, checked the pick up in the tank, check the roll over valve, cleaned the grounds.
Has new plugs, fresh cap and rotor, float levels look correct.

Here are the vital specs : 377 cid, Garete carb / Steve Taylor PRC carb, MSD dist, MSd 6al box, Blaster 2 coil, KSE tandem rear mount pump wit Barry Grant Regulator (pump mounted) running on gas. Car / motor / wiring / fuels lines / everything is 1 1/2 seaons old. Fuel pressure seems good, 4 psi at idle and right at 9 psi wide open.

Basicly at our wits end, really sux to have a front runing car that can't crack the top ten now. Was told Sat night to do away with the regulator and go to a bypass system.
Have never used this before and not sure where to go next.....

Any ideas from acrossed our great racing community?

Thanks, Stacy
MHM racing, Houston Tx.

powerslide
08-15-2011, 11:08 AM
have you smelled the air cleaner to see if it really is loading up and flooding over?

Do you really need 9psi on gas?

missile07
08-15-2011, 12:20 PM
Earlier this season I had a similar issue...as soon as I come off the corner the car would stumble and then pick back up. I was told by a ton of people that I was getting too much fuel. So I cut it back and still the same results. I went through my carb & whole ignition system....finally one night at the track I decided to raise my fuel pressure to about 6-7 at idle.....now it never misses at all.

Might be worth a shot and was an easy fix.

RACE5
08-23-2011, 07:06 AM
Just FYI,

Fuel pressure regulator fixed the stumble problem.

HRJ
08-23-2011, 11:18 AM
LOL. Good job.