I just took my 95 12.8:1 compression 383 LT1 to the track today and for some reason my car would fall flat on its face when I floor it in first gear around the 6250 rpm shift point I have set on the shift light. Then I would shift it into 2nd and as far as I can tell it runs great.

At first I thought that it was a fuel issue. I was spraying 2nd and third gear progressively so I thought that maybe the added fuel from the nitrous was making up for it and it was going lean at the top of first gear. So I thought I will spray first to see if it still happens with the shot of wet nitrous, but it still did it.

My revlimiter is set at 7000 in the computer (fuel cut off)and the ignition is set to 6500 so its not hitting the rev limiter because I am shifting at 6250, its more like the engine just drops out for a second then I shift into second. I also ran a scanner while racing and came up with no codes.

I am running the stock 24lbs LT1 injectors at ~50psi with a 255lph fuel pump, so I tryed adjusting the pressure up for the hell of it but now the regulators seems messed up.

What do you guys think is it fuel related? Should I go with a new fuel regulator and bigger injectors?

Thanks

Update:
I agree my injectors are small, I have a 12.8:1 compression 383 LT1. but I ran this motor last year, very same set up but I did not spray the nitrous and it ran ok. I remember a little break up off the line at part throttle but that cleared up when I floored it. The only thing I changed on the motor is the coil, I went with a promaster Malory coil to match my Hyfire ignition.

Ok I do not think that it is the fuel pump. But I know that I have been pushing my 24# stock LT1 injectors with my 383 12.8:1 compression LT1, so I just bought a set of Ford racing cobalt or blue top 36#. My aeromotive afpr is also jacked up from when I tried to adjust it last Saturday at the track, now the internal spring seems bound up and does not want to adjust properly. So I am also sending that in for repair. Aeromotive also told me that their pressure regulators are not designed to hold fuel pressure for 20 minutes after shut down like stock ones and immediate fuel bleed off at shut down is expected with their unit which my car always did and I checked the injectors and had no bleed off. And the last thing I will also get an other tune for the new injectors.

I hope this fixes my problem what are your thoughts?
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Good evening,

I'm not Injuneer but I experienced a similar problem on a Stock Eliminator LT1 Firebird I drove at a race a couple of weeks ago. This car has a Big Stuff management system and 24# injectors. The symptoms were a complete shutoff at about 7100 at full throttle at about the 1275' point on the track. It did it on every run, sometimes with a huge pop (scared the crap out of me the first time it did it) or a couple of smaller pops but by the time I got my senses back, well past the finish line, it was running fine. The owner tracked down his tuner and the tuner said he had set the shut-off at 7800, plenty high enough to handle the car with 4.88 gears in a quarter mile. Eventually, I asked the tuner to humor me and set the shut-off up to 8200. That stopped the problem completely. I suppose the bottom line to the story is that sometimes software plays tricks. From now on, I will either eliminate that feature from the equation altogether or set the limit up to 10,000 or so.

Good luck with your problem. Hope you find a solution quickly.

Chuck Norton

 

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Definately too small of an injector, do a search and you will find alot of good info on sizing your injectors for your applications/hp.

Cody