the pushrod itself isnt the prblm. its the o.d of the cup that the adj. screw sits in. this setup wrkd fine in the engine the rockers and pushrods came from only difference is the other eng. had a solid roller cam that had less lift. I had some Isky non roller rockers with the solid tappet cam and had no issues on the engine I switched the rollers onto. the other rockers look fine so i'm thinking maybe the lash was alittle loose and the pushrod came off the adjstrs ball.