Anybody getting back fires?

[Silver03Termi]

Im getting some pretty good back fires now that I'm running e85. I havent had the car on a lift yet, but I think there is a small exhaust leak in the x-pipe, and the back fire seems to come from under the car. I dont know if this might be caused from an exhaust leak, i.e. the exhaust hasnt had enough time to dissapate heat and the fresh air at the leak is making the back fire. Maybe plugs? Im running Tr6's gapped at .028-.030. 21-22 psi. Car makes good power and the back fires werent happening like this on the dyno. It had a small back fire, nothing like this though. Could this be tuned out with out risking running lean? It happens when I shift 3-4 or when I let off in 4th. Basically on decel at higher rpm under good amount of load. Thanks in advance. All relevant mods in sig.

 

[DHGTerminator]

Im getting some pretty good back fires now that I'm running e85. I havent had the car on a lift yet, but I think there is a small exhaust leak in the x-pipe, and the back fire seems to come from under the car. I dont know if this might be caused from an exhaust leak, i.e. the exhaust hasnt had enough time to dissapate heat and the fresh air at the leak is making the back fire. Maybe plugs? Im running Tr6's gapped at .028-.030. 21-22 psi. Car makes good power and the back fires werent happening like this on the dyno. It had a small back fire, nothing like this though. Could this be tuned out with out risking running lean? It happens when I shift 3-4 or when I let off in 4th. Basically on decel at higher rpm under good amount of load. Thanks in advance. All relevant mods in sig.

Sounds like what my old KB setup would do at WOT between 2nd and 3rd if I hit close enough to the rev limiter. I had a tuner explain to me that the car was loading up on fuel and then not needing to use it all, and thus spitting out flames because of it. I know it was a pretty rich tune all-around. Should be something that can be fixed in a tune.

 

[Silver03Termi]

this is how it was explained to me to by my tuner, however, my a/f is pretty good up top. how do you remove fuel to avoid backfires, without running lean?

 

[Silver03Termi]

anybody else?

 

[DHGTerminator]

anybody else?

You may have better luck posting this in the tuning section, since it's very possibly a tuning related question.