75Duster360

360 small block crate

it will make a ping/ knock sound for 3 seconds then go away

sounds like a backfire almost comes out one side of engine.

thanks for the help

TVLynn

Try backing the timing up 2 deg.. See if it still does it. May be a problem with the vacuum advance

Coronet 500

Good advice. I would also check all timing events with a light to know what I'm dealing with.

Knowing initial, mechanical, vacuum advance and at what RPM's they occur will help wih solving the current problem and any future troubles if you get into bad gas.

440roadrunner

If you run vacuum advance.......................

"All carburetors" don't have the same ported vacuum "kick in" characteristics. That is, even if you had timing and advance curve, and a vacuum can that was close, it might be that the carb vacuum might be coming in too soon.

I used to have this trouble with a Q-Jet on a 340 "back when."

moe7404

sometimes an exhaust leek sounds like pinging.

RacerHog

opcorn: I'll have to sit this one out....

75Duster360

This was the problem. There was a loose header fastener... Using a crush gasket caused the fastener to be too short and semi strip out.

Found a engine shop they said they can fix it better than using a HELIO COIL.
thanks for the help!

RacerHog

I'll Have to File that one for sure......