Backfire

[geostang351]

Hey, I just started my car after a AOD swap. No exhaust hookup right now, just open headers
The gas tank is pretty much bone dry but it started and ran rough! Whenever I let go the accel. it backfired hard. What is the reason for the backfire? What exactly IS a backfire?

 

[grego37]

check all your vacuum lines, maybe you left one un-hooked

 

[geostang351]

I did have one open. It was the old C4 vacuum hose, but as usual, nothing is that easy and it still backfired.

 

[geostang351]

Could it be the old fuel?

 

[67coupestang]

mine backfires every year when i pull it out of storage. bad fuel it usually clears up after carb cleaner, new fuel and about 30 miles for me

 

[geostang351]

Thanks.

Does anyone know what a backfire is?

 

[69Rcode_Mach1]

A little Off topic but here goes.

Hey Geo stang what kind of power are you making with that combo? I am just curious as to where that cam really picks up since it is what I am putting in mine. I don't exactly know the answer to your question sorry.

 

[krash kendall]

Raw uncombusted fuel exits through the exhaust port and is ignited causing the backfire. This can be caused by overcarburation, bad ignition or points, or in your case little or no backpressure. When my points crapped out, both my new mufflers were destroyed when they unexpectantly (yeah right, like I didn't see it coming) exploded.

 

[geostang351]

Raw uncombusted fuel exits through the exhaust port and is ignited causing the backfire. This can be caused by overcarburation, bad ignition or points, or in your case little or no backpressure. When my points crapped out, both my new mufflers were destroyed when they unexpectantly (yeah right, like I didn't see it coming) exploded.

I'll say you've got two out of three. My mixture is definetly more on the rich side. I have a petronix module so points aren't an issue and obvious not exhaust right now. Its just SO scary when I start it with open headers and then it bafckfires. Feels as though the whole car is about to explode!

69 - It powers up at about 4000 rpm but I really don't get on it too often. Maybe afraid of blowing it up or something breaking and running off the road. I got this cam more for its bark then bite. It sounds awesome.... very throaty. I think if the dog "sounds" mean, it must be mean. In short, if it sounds fast (to others) it must be fast