The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - SBC 350 Engine Backfire Through Exhaust and Carb

belowme51 · 04-21-2011, 05:11 PM

I had the same back fireing issue under acceleration from the carb and it turned out that the cam was beating up 1 lifter and eventually made a small hole in the lifter. I would check the lifters and make sure they are ok and if you find one that is bad or getting worn down than pull the cam and replace it and all of the lifters...it only takes one. As far as the motor being a flat tappet motor its crucial to break in properly and keep a zddp (zinc phosphorate) additive in your oil. No synthetics. Just my 2cents from experiance.

04-21-2011, 05:11 PM	#25
belowme51 Registered User Join Date: Mar 2010 Location: roanoke va Posts: 582	Re: SBC 350 Engine Backfire Through Exhaust and Carb I had the same back fireing issue under acceleration from the carb and it turned out that the cam was beating up 1 lifter and eventually made a small hole in the lifter. I would check the lifters and make sure they are ok and if you find one that is bad or getting worn down than pull the cam and replace it and all of the lifters...it only takes one. As far as the motor being a flat tappet motor its crucial to break in properly and keep a zddp (zinc phosphorate) additive in your oil. No synthetics. Just my 2cents from experiance.