AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
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I run my system at 207*F with a 1973 radiator. This is a 195 hi-flow stat that appears to actually be a 200 to 205. That sets the minimum cooling system temperature.
The thermostic clutch on the fan, sets the max to 207*F, by cycling as may be required. Around 30 mph, there is enough ram air thru the rad that the fan goes into freewheel mode and costs me nothing in terms of power or fuel useage.
I have a seven blade direct-drive fan, that I use for diagnostics. I wouldn't spin that bugger to max rpm either.
IMO,Your fan is adequate, but it does need to be in a shroud to be effective at low speed and idle.
A lower temp thermostat will only delay the inevitable on a prone to overheating engine, and only for a few minutes.
Eliminating the heater core, if you don't need it, is IMO a good thing, as it eliminates the coolant going round and round inside the pump. I did that too, and furthermore severely restricted the flow in the bypass hose. This helps my alloy heads warm up in a hurry. Then the stat opens and I'm gone. It can still take 2 to 4 minutes, at hiway speed for the rest of the engine to warm up. I can always feel the engine surge ahead 2 to 4 mph when it comes on-line. Now it's GO-TIME!
One test you can do, engine not running, is to run water thru the fins from a regular garden hose with no attachment.Put it up tight and the water should run right thru the rad without any back splash.
A second test is to check the difference in temp between the water returning to the rad, compared to that entering the pump. I like to see 30 degrees there.
Make sure your engine has enough idle timing; I like 14* minimum make sure the all-in is not excessive for your gas; on a fresh iron headed engine,I like 34 at no sooner than 3400. After you get to know her, you can sneak up on it.
The thermostic clutch on the fan, sets the max to 207*F, by cycling as may be required. Around 30 mph, there is enough ram air thru the rad that the fan goes into freewheel mode and costs me nothing in terms of power or fuel useage.
I have a seven blade direct-drive fan, that I use for diagnostics. I wouldn't spin that bugger to max rpm either.
IMO,Your fan is adequate, but it does need to be in a shroud to be effective at low speed and idle.
A lower temp thermostat will only delay the inevitable on a prone to overheating engine, and only for a few minutes.
Eliminating the heater core, if you don't need it, is IMO a good thing, as it eliminates the coolant going round and round inside the pump. I did that too, and furthermore severely restricted the flow in the bypass hose. This helps my alloy heads warm up in a hurry. Then the stat opens and I'm gone. It can still take 2 to 4 minutes, at hiway speed for the rest of the engine to warm up. I can always feel the engine surge ahead 2 to 4 mph when it comes on-line. Now it's GO-TIME!
One test you can do, engine not running, is to run water thru the fins from a regular garden hose with no attachment.Put it up tight and the water should run right thru the rad without any back splash.
A second test is to check the difference in temp between the water returning to the rad, compared to that entering the pump. I like to see 30 degrees there.
Make sure your engine has enough idle timing; I like 14* minimum make sure the all-in is not excessive for your gas; on a fresh iron headed engine,I like 34 at no sooner than 3400. After you get to know her, you can sneak up on it.
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