Gen VI Cooling Problem
I'm a tad late to the party, but I took interest in this post. I have a very similiar setup.
I have a GenVI 502, running 9.75:1 compression. Meziere WP300U water pump (55gph model). I have a Northern Racing radiator that measures 31x19. Timing is 38 total, 1050 dominator carb, 89 jets, stock bleeds. dual 12" puller fans, no shroud. Nothing in front of the radiator at all.
I've pulled out the thermostat completely with no success. As long as the engine is running it continues to build heat with no stopping. Since it's drag only, I make a pass then shut it down to cool if off, which it will do alright. Where I run into problems is back to back runs when that happens. If I start at 190 for the first pass, by the time I get back to make my second run, I'm already over 220. I'm not comfortable running over that temp, so I end up scratching. I've got a head scratcher. Going to try bigger fans and shroud to see if that helps. If it doesn't, going to tear down motor to see if something internal is causing the problem.
Any suggestions are greatly appreciated.