I have a 79 vette that runs hot. It has a new radiator, fan shroud, fan clutch, radiator seal kit, and radiator treatment mixed with the anti-freeze to make it run cooler. At speeds of 55 or greater the car will climb above 220. Driving 35 for a few mins will bring the temp down below 200. I have tried a 160 thermostat, and a ¾ restrictor plate in place of the thermostat. Would the timing be causing this, or do I need to switch to electric fans? Any help or suggestions would be greatly appreciated.

thanks
shark79

 

TIMING WILL MAKE YOUR CAR RUN HOT IF TO ADVANCED. ,HOW THE WATER PUMP,PUMP WILL MAKE IT RUN HOT IF NOT WORKING RIGHT,CHECK YOUR BELTS AND MAKE SHURE THEY ARE TIGHT,HOWS THE THERMOSTAT I WOULD USE A 180.WATER WILL MAKE IT RUN HOT TO.TRY SOME RED LINE WATER WETTER ADDITIVE.WORKS GREAT

HOPE THIS HELPS.

 

Does your car have the lower front air dam installed on the car? The air dam disrupts the air flow underneath and creates a vacuum, hence drawing the heated air behind the radiator out and down towards the vacuum. Next would be to check water pump flow, have seen impellers on the water pump rust off and not flow any coolant. Somethings to think about. [8D]

 

I have a front air dam installed on the car. It has a new water pump, but i guess i am going to have to check it, and the fan clutch. I have a 160 Thermostat installed on the car.

 

I DONT NO HOW MANY MILES ON YOU ENGINE OR IF YOU RAN IT HOT BUT YOU CAN CHECK YOUR HEADGASKET THAT WILL MAKE YOUR CAR RUN HOT TO IF IT IS BLOWN, JUST SOME MORE THINGS TO CHECK,DO YOU HAVE A STOCK CAM IN IT, AIR IN THE SYSTEM WILL MAKE IT RUN HOT TO,

 

The engine has 98k miles on it, but it was rebuilt at 96k miles. So the head gaskets are new, and it does not have the factory cam. It was after the rebuild i started having the problems, but when i reinstalled the engine, i put the new water pump, and fan clutch on. I have tried the water wetter in the coolant, and i have the correct coolant mix. I feel like there is something simple that is causeing it to run hot. Cause after 15 mins of running at 65 it will be at 220 and on its way over.

 

A couple of more things, was the intake gaskets the right ones? Some have restrictor or block off plates in the rear ports, another, are the head gaskets right and installed correctly? Easy questions to ask, hard to answer.

 

what size cam, lift and deration,stock compression?how many core raidator?are you shure you have no air trapt in the cooling system,?

 

My cam is 292. Timing is set at 32 before top dead center @ 2000 rpm. Eng was bored 30 thousands over, had big vales put in heads, heads were shaved, and motor is balanced. I am pretty sure their is no air in the system, and the radiator is the same as orginal.

 

Did you use your original temp sender? If you have access to an infrared sensor, check to see at the t-stat housing if that is your correct temp readings. Based on your descriptions, still think it is a slow water flow problem, in other words, the water is not circualting out of the block fast enough or in enough volume, since it overheats somewhat at speed. I'm running a 292 Comp cam in my '69 Camaro with a stock radiator with a/c and aluminum Victor Jr. heads and have no overheating probs at all.