18. Remember how we said these were Chevy connecting rods and pistons? Chevrolets use a different rod offset than Fords, so the offset on the big end of the rods need to be turned down in a lathe (using a custom fixture) so that they won't rub the cheek of the crank. This also means that the inside of the pin bores often needs to be massaged to keep the pin end of the rod from rubbing. It's a labor-intensive process, but one Charlie says pays off in both power and durability.