65 "389" temp runs at 190 no matter what I do?
I can't get the temperature on my 65 Pontiac "389", 4 speed, 4 barrel, to run at less that 190 degrees once warmed up! I have installed a fan shroud, clutch fan, and 160 degree thermostat. On very humid days, I get what we used to call "vapor lock", the car stalls out after it is warm and turn off the engine for a little while and then start it up again. It starts ok but stalls out and I have to press the gas pedal to the floor and hold it there until the engine refires. After reading the many posts on PY online forums concerning "67 GTO running hot", I am wondering if the problem may be the 410 posi rear end in my car? At 60 miles an hour I am tacking 3000 RPM's. One of the guys posted that 3.23 gears would make the car run cooler. What is the cheapest way to change the gears in the rear end?
|