Hello everyone!! I am looking for some knowledge about 1966 340-4. My engine has started tapping right a 500 miles on the break in. This is the second time I have rebuilt this engine in 6 years. I broke the compressoin rings in four cyclinders by running to small a radiator. ou: This time around I put a performance cam, bored .060, heads reworked + shaved a little, Dish pistons. As far as the valve train. I replaced the lifters and pushrods from crane. I did not change the Rocker Assymbley. I can tell where the sound is coming from, it is my top driver side toward the front around the splash guard. My dad thought he pen pointed the first lifter to be bad. We order one lifter and put it back together. Yep still tapping but not as bad. The tap goes along with RPM. I called the guys at TA Performance and he told me that I had the wrong type of lifter and push rods. The pushrods I took out of the engine were solid at the ends, the ones I have now have a hole in the center for oil I guess. The guy at TA said for my engine I should not use crane Hydro. lifters. They sell at least three different kinds anti-pump, Fast Bleed, and a special race lifter. My rockers look worn a little so I am going to take some off a 300. I think the tap is between the lifters, pushrod, rocker assy. Someone give thier opinion please.
