cooling problems on a hot rod.

I have a chaneled 26 t coupe with a 31 a grill shell.
The motor is a pontiac 400 w/ a 160 degree thermostat. No hood or fan. The radiator is a 64 mustang. I have a junk yard electric fan (puller) on it.
The car cools great around town, and stuck in heavy traffic. It runs right at 210-220.
If I try to drive it on the interstate at 65 mph , it heats up past 230+ within 5 miles.
Any suggestions, solutions?
thanks ,jon

 

post this on the main page instead of in the introduction's page...youll get more answers! and welcome to the HAMB!