My car seems to have a cooling problem at idle. At stoplights, the water temperature doesn't hesitate to climb to 210-215, even on a mid-80's day. However, if I revv the engine to about 1200rpm while stopped, the temp quickly drops by about 15-20 degrees and stays there. My water pump pulley is 6.5", and the crank pulley is also 6.5" in diameter. I have a very mild engine making only about 280hp, original 4 core radiator, fan shroud and flex fan which is 1/2 way into the shroud. I changed the thermostat from 195 to 180 to 160 with hardly any change in temperature. Coolant/Water ratio is 50/50.
Is my problem a matter of getting a smaller water pump pulley or a bigger crank pulley, or is there something else you can think of? Thanks
355, Comp XR236R Solid Roller, Air Gap, Pro Systems Double Pumper,
TKO, 10lb flywheel, 3.73 rear, Global West Suspension, Corvette C5 brakes
3098 lbs (and falling!)