Well, i don't really know from 1st hand experience what was going on at the time the car overheated. He gave me a call and i went to help him out. All i really know is, the car overheated to the point where the engine shut down. I replaced the water pump and radiator for him. When we went to fire it up, no spark at the plugs. Replaced MSD box, fires up now, but will not remain running.
I was just as puzzled as you about the timing. The reason why i'm leaning toward the timing chain is that no matter how much i try to adjust the timing, i can't keep it running without holding the accelerator down a little. Also, it has a pretty good spark knock that i can hear at different rpm's. Knocking is not constant at all rpm's. Knock comes and goes as the engine is revved.