BAck fire .

[sbcCuttY]

so i just got done ..well at last i thoght i was..with my 350 swap in my cultass...and i cranked it and right away it backfires....can anyone give mesome tips on what could be wrong........
the motor was running perfect before the swap...

 

[85 Cutlass Brougham]

Is your timing 180 degrees out? When you dropped in your distributor, it can either go in correctly or 180 degrees off. The fool proof way to verify this is by pulling the valve cover that is over the #1 cylinder and verify that the valves are closed when at TDC. It's a common mistake that everyone makes from time to time, even if you have done it a number of times before. Remember that rotor phasing is what is important relative to the position of the #1 plug wire on the distributor cap.

 

[megaladon6]

that's definately the most likely, also double check your ignition wire routing. i repetitively cross 5 and 7 for some stupid reason.

 

[85 Cutlass Brougham]

Yeah, that's true. He did not state weather it was a carb backfire or an exhaust backfire, weather it was running or not, etc. I just posted the most likely for a non runner thru the carb backfire. If it is a different scenario, please post what is actually happening within the set of parameters I listed.

 

[ryanwitski]

that's definately the most likely, also double check your ignition wire routing. i repetitively cross 5 and 7 for some stupid reason.

ha ha i did that too!

 

[sbcCuttY]

and its a carb backfire.....were about to look at it carefully..ill b back wit the reslts if we find anything....

 

[sbcCuttY]

well it is the carb.
somehow during th process of the swap it got discalibrated.....

 

[ryanwitski]

that's typical stuff. You always have to fiddle with stuff when doing things like that.

 

[bigdan]

if distributor was not removed but just loosen & wires ere at the right place ....you need more advance
Dan