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Join Date: Aug 2008
Location: Central Alabama
Re: misfire popping sound through exhaust help with plugs
I hope your carb guy checked for a ruptured power valve, a fairly common problem when it backfires through the carb. You may still have a vacuum leak, check torque on intake bolts and make sure your carb gasket is sealing properly to the intake.
Searching for vacuum leaks can be frustrating, here's my method: Get a can of Gumout choke & carb cleaner and spray any spot you suspect a leak while idling the engine. If idle speed goes up when you spray a spot, you've found your leak.
Your plug gaps look really wide, have you set them to the spec for the ignition system you have?
TC # 5401
67 Project SS Clone
Owning a Chevelle project is like having a giant-size piggy bank that you keep pouring money into....but you can't get it back out.