I forgot to ask the most important question which is how hot is it running? is this with a known good mechanical gauge? I'm assuming you are on ported. what is your initial? when you are moveing what does the temp drop to? Was it OK before the original rebuild? (if that info is available). how far into the shroud is the fan located? how many blades? was the rad rodded out or a new core (which it sounded like).