I live in Houston, temp is always 95 - 99F with 70% humidity. My fan kicks on automatically at 90C so the temp never goes above that, if I overide and turn the fan on with the switch I stay at 80C on the cooling and 85C on the
oil. I have sat with the sun baking down in stop and go traffic for 45 minutes before and with the fan on cooling water stayed at 80C. Roush 427SR. Are you sure your fans are comming on? One thing I admire about the spf is the detail behind the scenes such as how the opening around the radiotor is completley sealed so as all the air must pass through the radiator ensuring cooling.