I checked the heat valve on my 65 283 after reading your disscusion, it is free and manually flips up and down, but it stays down even when its hot (need new springs I guess). Does this mean that the exhaust air continually heats the intake? Can this cause overheating? Also, I have noticed that my passenger side tail pipe (dual exhaust) is always cooler than my driver side tail pipe. Does that have something to do whith the heat spring valve being on the passenger side?
Bullhead
