235 cam cores have flat areas between the lobes to account for the longer stroke, so that would be another option. Does the interference happen between the rod cap itself and the cam, or the bolt and nut assemblies? I'm planning to run the 261/Corvette cam in a 216 by turning the bearing journals down to 216 size. Those cams already have the long stroke relief built in. I'm putting 3/8-24 Helicoils in stovebolt rods, and using ARP style 12 point rod bolts that give the bolt approximately twice the thread engagement as a conventional rod bolt and nut. Obviously, I'll recondition all the rods after installing the super strong bolts to assure the bore is round and the right diameter.
Jerry

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