A31HPAxle, there's one thing you left out. Sometimes a FLAT (worn) EXHAUST CAM LOBE can cause backfiring, (at least on certain cylinders) because the flat lobe acts like a "cork" because it's not opening, and will cause the cylinder pressure to blow up back out the intake when that valve is open. This of course could be caused by other things like a bent/ broken pushrod.


Let me add a little to the "static" timing method. Someone else was indeed correct about the cam drive marks. When many V8 cam drives are "lined up" according to the book, they are "no 6 ready to fire" and not no 1.

Hell, when I got my first 57 Chivvy, I didn't even KNOW there was a "certain" way to install a distributor.

Pull no1 plug, Rotate engine with a remote starter or wrench, holding your finger in no1 and watching the timing marks. As the marks "come up" on the wheel, and as your finger gets blown out of the hole, THAT is approaching no1.

Stop the wheel, at , anywhere around 10BTC, 15 BTC.

Install the dist, and note where the rotor points, THAT will be no. one.

Mark the rim of the dist. to match the no1 tower

Rotate the dist COUNTER clockwise to close the points. SLOWLY rotate the dist CLOCKWISE while doing one of the following:

With a 12V test lamp from coil neg. to ground, move the dist until the lamp lights --or--

leave the ign on, and watch for a spark. Easy way to do that is stick a spare plug on the coil wire, to ground.

THIS METHOD if properly done, should allow the car to start right up and run.

ALSO, "spring" the rotor, to check fo proper freedom and operation of the advance and springs. You should be able to "spring" the rotor CCW and it should spring freely right back.

Also, you might find a troublesome cylinder by getting it running as well as you can, pull the boots loose at the dist. towers, and then push a prod--test lamp or small screwdriver, etc--down between the plug wires and a clip to ground. You can now ground one cylinder at a time, and it might tell you which "one(s)" are backfireing, then check them out for valve trouble, etc.