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I have a 1964 1/2 coupe restomod that has an overheating issue that has me stumped.
Background info:
- Block year is unknown. I haven't taken off the starter to check.
- Heads are believed to be '70's era (5/8" plugs).
- Holly 4-barrel carb.
- Cylinder compression is 177-180 throughout the motor.
- Standard water pump (C80E-D casting).
- 185 degree thermostat. Installed correctly - I promise!
- C4 automatic transmission (later model based on shift pattern).
- 9" rear end, 3.00 gears.
- 2-row aluminum radiator (1" tubes). Leak-down test conducted and passed with flying colors.
- Derale elctric fan (16926) pulling 2200 CFM.
- Classic Auto Air a/c under the hood, 1965 Ford in the cabin. Runs great.
Issue:
The car gets to about 180-190 at idle and while driving around town. Won't get above 195 even sitting in traffic for long periods of time. When driving for over 5 minutes at over 2500 RPM, the temp climbs to 210 and over (that's when I slow down and let the temp drop). Fan on or off doesn't seem to matter at highway speeds - it still gets hot. One weird thing I noticed is that the UPPER hose was seen to collapse at 2600 RPM, so I inserted a spring. There was already a spring on the bottom hose. The heating issue continued.
I was told I was pumping almost too much water at idle, and not nearly enough at higher revs which may be due to the impeller slipping on the shaft(?) - replacing the water pump with a new (not rebuilt) unit this weekend just in case.
The only other reason for overheating I can think of is a block/head mismatch that is causing some sort of restriction in the water flow. That's going to be checked this weekend.
I'm out of ideas. Has anyone else see this problem before? Any solutions?
Thanks,
Dave
Background info:
- Block year is unknown. I haven't taken off the starter to check.
- Heads are believed to be '70's era (5/8" plugs).
- Holly 4-barrel carb.
- Cylinder compression is 177-180 throughout the motor.
- Standard water pump (C80E-D casting).
- 185 degree thermostat. Installed correctly - I promise!
- C4 automatic transmission (later model based on shift pattern).
- 9" rear end, 3.00 gears.
- 2-row aluminum radiator (1" tubes). Leak-down test conducted and passed with flying colors.
- Derale elctric fan (16926) pulling 2200 CFM.
- Classic Auto Air a/c under the hood, 1965 Ford in the cabin. Runs great.
Issue:
The car gets to about 180-190 at idle and while driving around town. Won't get above 195 even sitting in traffic for long periods of time. When driving for over 5 minutes at over 2500 RPM, the temp climbs to 210 and over (that's when I slow down and let the temp drop). Fan on or off doesn't seem to matter at highway speeds - it still gets hot. One weird thing I noticed is that the UPPER hose was seen to collapse at 2600 RPM, so I inserted a spring. There was already a spring on the bottom hose. The heating issue continued.
I was told I was pumping almost too much water at idle, and not nearly enough at higher revs which may be due to the impeller slipping on the shaft(?) - replacing the water pump with a new (not rebuilt) unit this weekend just in case.
The only other reason for overheating I can think of is a block/head mismatch that is causing some sort of restriction in the water flow. That's going to be checked this weekend.
I'm out of ideas. Has anyone else see this problem before? Any solutions?
Thanks,
Dave