What we know right now
- Overheats at idle in 20 minutes, should not do that
- Overheats in 5 miles at speed, should not do that
- Op had same problem with and with out the shroud, not an airflow problem at speed, might be at idle?
- Op did not have the problem with a turbo
- Op gutted the thermostat which should have increased water flow
- Had closer to 1 to 1 pulley that was thought to be posable cause for overheating, smaller pulley did not fix the problem
- Op has a 20 percent overdriven water pump pulley now.
Am I missing anything?
There are two different issues at hand. Seems like the same issue but really it's not.
At idle very little heat should be produced, so a very small radiator should be able to cool the engine all day long assuming the water flow and thermostat and fans are working properly
At speed there is much more heat produced, there is also much more air and water flow. So a properly sized cooling system should be able to handle that situation as long as the thermostat and pump are functioning properly.
So if the cooling system is sized and working properly for speed it can easily cool at idle as long as it has a property sized fan
If the cooling system is undersized for speed AND the fan is undersized for idle then you could have the issue you are having.
