Contrary to popular opinion, the GM engineers in the 30's, 40's, and 50's were not a bunch of rubes who just fell off the turnip truck!
Jerry
Hehe! I wish we had the roll on floor laughing smiley on this forum!
This seems like a good point and I am a fan of the stock exhaust manifold coupling.
I'd speculate that hot air makes carburetor happy up until the point where the float bowl reaches vapor locking temps ~130°F ... assuming a hot day with a return system and 90-100°F fuel going into the float bowl, the worksheet indicates that intake air should be limited no higher than ~150°F in order to prevent gas from overheating in the float bowl. On cooler days when the fuel entering the carb is cooler even higher intake temperatures are no problem.
This supports the reasoning of later engineers adding thermostatic intakes, though not sure if the temperature estimates of this calculator are any good.
