I found a '66 C10 in south texas that was in a barn on blocks. the guy who owned it parked it there 20 + years ago and says that it ran good when parked. We changed the oil, put a new fuel pump on it, put in new fuel and it fired up and sounded pretty good. Very good oil pressure and didn't smoke very much at all. It would pop through the exhaust and through the carb every so often. The enginie only has 80K on it. I have taken the engine down to a long block cleaned it up, put a .447 lift / 222 @ .050 camshaft into it with new lifters, roller rockers, and pushrods. New sparkplugs, new timing chaing, new edelbrock 4 barrel carb, new hei distributor, new wires, etc. I also put in umbrella seals on the valve stems, no broken valve springs, everthing looked good. I fired it up and broke in the camshaft and everything looks pretty good except for a couple things. It has periodic popping through the exhaust on the even side of the engine. I am guessing a sticking valve. The best vacuum that I can get is 13 to 14 inches that is pretty steady. I am guessing the long duration cam is the fault there. I have done a compression test and all of the cylinders cold registered between 120 to 150. I am thinking that it probably just needs some Rislone and driven a few miles to loosen everything up. I am sure that there is a lot of carbon build up in it. I have ran decarbonizing fluid through the carb and it really helped a lot, except for the periodic popping. When it pops it throws flame out. That is why I am thinking sticking valve. I have double checked the valve setting and it is right. I set them all a half turn past zero lash. (It is a hydraulic cam). Am I on the right track here or do yall think there is some other problem going on here ?
