As long as I brought this up, a little data for you guys driving cross country with your 4 cylinders. My car is wired and gauged for CHT readings. When I drive normally in traffic with the Raby kit motor the CHT is usually around 275 F. That is until you go to fifth gear. In fifth gear the temperature rises by 50 F. or so. Now with a stockish 2 liter the CHT is about 50 F. higher than the Raby kit motor. So just driving around you sit at about 300 F. Go to 5th gear at highway speed and your temperature rises to 350 F. These temperatures are at a fairly cool ambient of 70 F. and are compensated, so they are actual temperatures.
The take home message is if you are on the highway in high ambient temperatures and in fifth, be aware of your oil levels and try to spend some time in forth gear once in a while. I suspect you are ok having your temperatures rise by 50 F. but absolutely do not forget to downshift when you go up a grade.
You guys with stock exhaust will have higher CHT. Fan speed seems to have the greatest impact on CHT, but don't let your oil levels drop!
Isn't that kind of hot? Do you have a cooler?