Sounds like a radiator issue to me, I was running a Stewart pump, 180 thermo and a Flex fan and ran about 210 degrees, then I switched to the Ron Davis Racing radiator. After the install I needed to run a 195 thermo just to get the motor to run 180 degrees, which the stock EEC needs or it add fuel and retards timing. I just switched to a Perma Cool fan. I paid $269.00 for my Ron Davis through Tommie Vaughun or Downs FOrd also sells them.
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