pushrods

[Knarley Darley]

My eyes were opened to pushrod integrity during engine assembly one time. We were assembling a BB with 3/8 chromolly pushrods and rotating by hand while measuring actual valve lift at the valve with a dial indicator. Then we switched to a 7/16 pushrod and the lift increased .015 at the valve which means the if the smaller pushrod was allowing that much deflection at hand rotating speed, what was happening at 8000 rpm! I personally have Smith Bros. taper wall (1/2" at the thickest point in the center) pushrods with the special ends, and all the wazoo features, and when I rebuilt the engine this last time I noticed polish marks on some of them in the middle where they are about .050 from touching the head which means they are still deflecting at least that muchand hitting. The other thing I noticed is the cam belt walks to the rear of the cam sprocket when you rev the engine from cam deflection!!!! Yikes there are a lot of forces at play here

[squeeezer]

well i did order some 3/8 pushrods and raised guides

unfortunately (adam) they required a 7.700'' length