I have a problem that is driving me nuts. 1962 Chevy Biscayne, 283. The engine was starting fine until a couple of months ago. Then, the engine wasn't turning over so I replaced the starter with a rebuilt Delco and I replaced the battery. I cleaned the battery terminals and cable leads. After that, the car was starting fine when cold. After it is warmed up, it will not turn over unless it is boosted or if there is a battery charger hooked up to the battery. It has headers and a Moroso heat sheild around the starter. The mechanic at the corner is suggesting that the starter is being cooked by the headers. I tried a remote starter switch while the problem is present and that's not working either. How can i fix this? Do I need a heat sheild wrap around the starter? Is the battery too wimpy?(795 amps CCA, 1000 amps 32 degrees F) Help!