the engine has a mild cam, has edelbrock intake, edelbrock carb, a free distributor with new cap and coil, new wires, custom exhaust; headers to mufflers thats it no cat, the problem is that i got it to where it would run alright but, it would always backfire out the exhaust when i revved it up and then let all the way off the gas. has anyone had this problem? could it be a carburetor problem? a distributor problem? i'd really appreciate some help with this, i havent been able to drive it in a while and its getting really disheartening. thanks guys!

 

What distributor? Where is the timing set? How did you set the timing? What induction was on the car originally (carb? TPI? V6?)?

 

im not really sure what brand it doesnt say on the distributor, probably delco-remy. i have no clue where the timing is set, btw the timing tab for this block is no longer on the block and it was the kind that was straight up and down, not off to the side. i never owned the car with the original engine, when i bought it it had a very clean 305 which was carbureted. the 350 that is in it now was a crate engine that didnt have intake on it. hope this helps you to help me! thanks a bunch man! oh by the way my grandfather seems to think that because it has a cam, the counterweights in the distributor may have to be different? is this true?

 

Check Firing order.
Check to be sure all plug wires are securely on the plugs.
Check continuity on each plug wire to be sure there isn't a break in a wire.
Timing is going to have to be checked somehow - I'm lost on that when there's no tab left to see against.

How is fuel delivered to carb? In-tank pump with regulator? Mechanical pump on block? What's the fuel pressure just before the carb?

 

it has an electric pump probably in the tank, and a mechanical pump on the block. no idea what the fuel pressure is. the firing order is fine, there's no issue of getting spark, just when it sparks.

 

maybe if you could explain why fuel pressure would make it backfire? anyone else have any ideas? do the dist. counterweights have anything to do with it? thanks... you know what REALLY bugs me about all this....? the fact that i paid a "mechanic" to do it, and when i picked the car up, it drove down the road like a drunk ox. ugh....

 

Get a timing tab on it and set the timing properly.

 

apparently this engine needs a timing tab that is directly above the h.b. instead of off to the side like most, where do i find one of these?

 

would it be possible that i would be running rich and the extra gasoline would be let out on the exhaust stroke and then igniting in the exhaust causing the backfire? also the engine seems to miss or hesitate

 

Check summitracing.com

Until the timing is set properly, there isn't anything else you can do.