Frank Enstein
Best. Day. EVER!
I get lots of overheating calls @ work. I define overheating as running outside of 5 degrees +/- of the thermostat opening temp/fan engage temp.
#1 Too much antifreeze in the mix.
I recommend zero degrees F freezing protection or 10 degrees F colder than the vehicle will ever see.
You need some antifreeze for corrosion protection and water pump lubrication.
The radiator manufacturers I have spoken to do not recommend distilled water to cut the antifreeze but rather drinking/mineral water. They say the distilled water will leach metal out of the cooling system.
You can run a product like Redline "Super Cool with Water Wetter" or Royal Purple "Purple Ice" and just water with no antifreeze if the vehicle will NEVER see freezing temperatures. Those products do not have any freezing protection at all.
Those products will need to be replenished every other year. They will prevent corrosion and lube the water pump seals too.
Those products can be used with antifreeze and it still helps heat transfer.
#2 Not enough ignition timing @ idle
This is mostly carbureted guys that "my buddy" told them to get a mechanical advance only distributor because the vacuum advance is for emissions/will cost 50 horsepower.
#3 Overheating @ highway speeds
Often this is poor airflow management.
Make sure any air that comes in the grille HAS to go through the radiator to get out.
Make sure All the air pulled through the fan HAS to go through the radiator.
You would be impressed by how much the coolant temp will drop when an efficient air dam is fitted.
It's not as much shoving more air into the radiator but pulling the air out of the engine compartment by creating a low pressure area behind the radiator.
I fooled around with this on my Firebird a long time ago. I made a ridiculous air dam that nearly touched the ground out of flashing and duct tape and let it beat itself to death with normal driving. I then made a real air dam 1/2" shorter (less deep) and it dropped my coolant temp 15 degrees F on the highway.
I did the same with side skirts and dropped it another 10 degrees F. I learned lots that summer!
One of the problems with electric fans is there is no standard for how cfm is measured.
A 2400 Perma-cool fan that draws 10 amps Flex-a-lite will call that same fan 1050 cfm.
The only company that lists it correctly is Spal. They tell what voltage, amperage, rpm, and static restriction on their website.
As a decent rule of thumb 100 cfm per amp is generally correct.
I recommend at least 2400 cfm for primary cooling. I also sell the biggest highest cfm fan that will fit in the available space.
If you buy too much fan it won't run as long. If you don't buy enough fan you buy it twice.
If your vehicle runs hot @ idle but is fine on the highway an e-fan is a good choice. In most cases (NOT heavy towing) you don't need a fan above 30 mph if the airflow management is o.k.
If the engine runs at normal temps in traffic but the A/C isn't great @ low vehicle speeds an electric pusher fan can help.
Pusher fans are 20% less efficient than the same fan used as a puller fan.
If it won't keep cool on the highway you may need a more efficient radiator if all other factors have been dealt with.
#1 Too much antifreeze in the mix.
I recommend zero degrees F freezing protection or 10 degrees F colder than the vehicle will ever see.
You need some antifreeze for corrosion protection and water pump lubrication.
The radiator manufacturers I have spoken to do not recommend distilled water to cut the antifreeze but rather drinking/mineral water. They say the distilled water will leach metal out of the cooling system.
You can run a product like Redline "Super Cool with Water Wetter" or Royal Purple "Purple Ice" and just water with no antifreeze if the vehicle will NEVER see freezing temperatures. Those products do not have any freezing protection at all.
Those products will need to be replenished every other year. They will prevent corrosion and lube the water pump seals too.
Those products can be used with antifreeze and it still helps heat transfer.
#2 Not enough ignition timing @ idle
This is mostly carbureted guys that "my buddy" told them to get a mechanical advance only distributor because the vacuum advance is for emissions/will cost 50 horsepower.
#3 Overheating @ highway speeds
Often this is poor airflow management.
Make sure any air that comes in the grille HAS to go through the radiator to get out.
Make sure All the air pulled through the fan HAS to go through the radiator.
You would be impressed by how much the coolant temp will drop when an efficient air dam is fitted.
It's not as much shoving more air into the radiator but pulling the air out of the engine compartment by creating a low pressure area behind the radiator.
I fooled around with this on my Firebird a long time ago. I made a ridiculous air dam that nearly touched the ground out of flashing and duct tape and let it beat itself to death with normal driving. I then made a real air dam 1/2" shorter (less deep) and it dropped my coolant temp 15 degrees F on the highway.
I did the same with side skirts and dropped it another 10 degrees F. I learned lots that summer!
One of the problems with electric fans is there is no standard for how cfm is measured.
A 2400 Perma-cool fan that draws 10 amps Flex-a-lite will call that same fan 1050 cfm.
The only company that lists it correctly is Spal. They tell what voltage, amperage, rpm, and static restriction on their website.
As a decent rule of thumb 100 cfm per amp is generally correct.
I recommend at least 2400 cfm for primary cooling. I also sell the biggest highest cfm fan that will fit in the available space.
If you buy too much fan it won't run as long. If you don't buy enough fan you buy it twice.
If your vehicle runs hot @ idle but is fine on the highway an e-fan is a good choice. In most cases (NOT heavy towing) you don't need a fan above 30 mph if the airflow management is o.k.
If the engine runs at normal temps in traffic but the A/C isn't great @ low vehicle speeds an electric pusher fan can help.
Pusher fans are 20% less efficient than the same fan used as a puller fan.
If it won't keep cool on the highway you may need a more efficient radiator if all other factors have been dealt with.
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let me know if you want to know what fan that combo ran. (I "think" it has the fan?...)
