Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
hello I can assist you . The Popping sound you are hearing can be caused by incorrect valve lash setting or a bad camshaft . Worn camshaft lobes on the exhaust lobes was a fairly common fault with some small blocks some years back particularly on cylinders number 5 and 7 . Not specifically on 327 engines but I would strongly suggest you start there . remove the valve covers and check the rocker arms for movement . Worn cam lobes will be quite obvious as you can visually tell that there is not " full " lift at the rocker arms . check that and get back to me . Aalso over tightened intake valves ( lash ) can give the same issue . Also double check the firing order to make sure it is correct .
how are you making out with your issue ?