The car in my avatar had overheating problems since it was first built about 15 years ago. I tried everything that I could (shrouds, mech fans, electric fans, high volume pumps, standard pumps) and nothing worked.

The car came with a massive 5 row custom built copper radiator when I bought it as an unfinished project.

Last year I got completely fed up with it and redid the entire cooling system. I used a Griffin 2 row aluminum rad (one of their Rat Rod series)and a Cooling Components puller fan. No over heating now. The CC fan requires either 2 40 amp relays or a single 70 amp relay. It moves a lot of air. I think the free air rating was 2700 cfm, but as said, that means nothing.

We did the Hot Rod Power Tour this year and that required lots (LOTS) of idling in stop and go traffic. The system did great. No overheating.

I actually think the original rad was the problem. I couldn't make myself believe that the giant rad wouldn't cool, but apparently it wouldn't.

BTW - If you do run an electric fan, make sure your alternator is up to the task. My old style (CS 12?) GM unit is supposed to be a 97 amp unit, but it barely handles the CC fan. Even though it charges, I'm beginning to think it's not putting out what it's rated for.

Mike