Bomba_MC

Just looking for a general consensus on what is more apt to be the problem when the engine only after fires (or backfires) on deceleration. IF its isolated to the fuel mixture, is it because it is running too rich OR is too running too lean. Seems I get mixed reviews from people I have asked at car shows.

Nowhere Man

I double check your timing

Bomba_MC

Timing checked and is right on.

Greg

Bomba, is your backfire through the exhaust or up through the carb?

Frankie the Fink

After fire in the exhaust pipe is timing or a lean condition in most cases. Make sure your exhaust manifolds are tight. .

thoyer

Did you just check the initial timing or did you also check the advance curve through the RPM range. Double check your dwell at the higher RPMs also. If you have a vacuum advance, double check that the advance diaphragm can hold vacuum and not leak.

An old saying that I have found to be true more often then not - most carburetor problems turn out to be ignition problems.....

Tom

Mark Lovejoy

I'm with FTF, I would look at the ignition system.

Mechanical advance curve and vacuum advance. If you are not 100% sure of the two advance systems have your distributor checked by a competent shop.

My 2 cents

6D2148

Sounds like timing to me. You say timing is right on, but have you checked if tdc is really tdc when the pointer says it is? Chip

Bill Pilon

Look for a vacuum leak, back in the 50's we used to induce a vacuum leak, usually by pulling off the windshield wiper hose, to make it "rattle" off good when backing down.

Bill

63two

It sounds like a ford thing. my 55 ford vic would pop and pop going down a long hill. I"ts caused by an exhaust system that is not quite as tight as it should be. No harm ,Enjoy the noise . It is a sports car
!!