ksk454

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.

CamBirdRacing

I have that problem every time I change engines out. I found out that the new engine (old block) rusts on the inside and after running it, the rust breals loose and plugs the radiator. I will get the radiator cleaned out and it fixes the problem.

Jordan1984

I had a over heating problem in my sbc before. Mine was due to a dead cylinder- I wiped the lobes off of the camshaft by not adjusting the valves right and the engine had to work harder, with more timing, to make power. I changed out the cam, added an electric water pump and it solved my problem. Just a shot in the dark, but it may run hotter than stock motor and bore due to the thinner cylinder walls from the .40 over bore.
JMO

cepx111

FYI .040 is not thin for a big iron.

Jordan, didnt you notice a dead miss with that cam wiped out?? Or did you think it was just hittin hard.

You just bumped the timing up and poured the coal to it huh...lol
Too funny.

StrokersGraphics

this is somthing i have seen several times, you must restrict the flow at the thermostat housing. i just gut a thermostat put it in.

NOW!! my real question is what pound radiator cap are you running? you need at least 18lbs. i run 22-24 lbs on my radiator. what happens is if you don't run a large enough cap the rad fluid evaporates and/or lets the fluid pass the cap and fill your overflow catch can.

if this does not work you might want to take the heads off and see if you have a blown headgasket.