I helped a friend with a high compression 327 on a 67 vette. His starter was right next to the headed and would heat up while the car was running. He'd drive 20 miles park at a store, and not be able to restart the car until the started and the engine block cooled down. We used a gear reduction model like Jerry mentioned from Summit Auto. Never has been a problem since then, also it's a hell of a lot smaller than the stock starter, i.e. more room to work with and larger clearance from hot exhaust.