watch the video. just after the 2nd race when we are slowing down, right after the truck comes back past the A-pillar, a big flame shoots out my exaust

http://video.performancetrucks.net/p...1-B143C86A02E0

i am running pacesetters and the ORY, and i was spraying a wet shot. but i had long since gotten out of the nitrous and let off of the gas pedal.

what could have caused it? the cutout was open so it seems very odd to me that the flame would come from the turndown after the stock muffler....

 

I couldn't really tell from the vid., but was it when you let out of it? Since you got the ory I'm guessing it could just be a backfire.

 

Looks like fire to me Tony I don't know what it could have been if you had been off the throttle for a while?? Maybe trying to intimidate the LS1 truck?

 

If that's right after you let off, then its unburnt fuel burning as it hits the cold air. It happens with roundy-round cars everytime they let off the gas when going into a corner.

 

Unburned fuel and the nitrous and no cats probly doesnt help your little flame problem. Mine does it when i rev it up and let out of it while in Nuetral, and i imagine that it does it when im givin it a run. I think you should be ok as long as you dont catch your truck on fire

 

FullthrottleDan and I had something like this happen after our 1/4 runs, but the gas did not ignite. Just white smoke looking puff out the back. At night I have had guys tell me that my truck throws sparks after a race, or between shifts!? Maybe they are seeing just a flame.

BUT - I have ported stock manifolds stock Y-pipe and a 40 flowmaster dumped.

 

i thought about the unburnt fuel thing to but:
a) i had been out of the gas for a while. it had prolly popped (normal light popping i get when the cutout is open) 3-4 times already

b) would the fuel really make it all the way to the muffler with the cutout open? my cutout is a mere 4-5 inches in front the muffler but i figured it would leave through the cutout before making it to the muffler

it hasn't done it again, even one time when i sprayed it with the cutout closed, so i'm not all that concerned about it. now i'm just curious as to how/why it happened.

like white1 said, if i could reproduce it on demand it could be real intimidating

 

Undurned fuel and cold air in the pipe... With your cut out in place and open, does it close when off WOT or manually... Also straight pipes no cats and a little muffler at all. But the fuel is the ticket once lit gots to go somewhere... There is a company that makes a flame thrower add on kit... NOW that would scare the crap out of the other guy.
Ricky

 

Looks like unburned fuel to me.

Check this out, a stock STI with a catless turboback exhaust. He said this is mostly because the STIs are tuned so rich from the factory.
http://kingofimports.com/videos/Ben'...%20TBE%205.wmv

 

Unburned N20/fuel and a lean spike. Usually denoted by a pop upon lifting off the throttle rapidly.