I realized I "misspoke" when I used the word [backfire}. You are correct it is more accuratly applied to when the combustion pressure comes out the intake. Unfortunatly once you hit [send] it is too late to change anything! The point I was trying to make is the same anyway which, as you agree, the timming of either the valves or distributer is way off to allow the combustion to escape prematurely. This can become dangerous because it can cause pieces to come apart and go flying. It can also damage your hearing besides damaging parts of the motor. David Teitelbaum vin 10757 --- In dmcnews@xxxxxxxxxxxxxxx, "content22207" <brobertson@xxxx> wrote: > Actually, this was technically a muffler explosion, not a backfire. > Backfires go backwards towards intake (flames out of carburetor), > muffler explosions go forward. >