Funny that you replied today. I just returned yesterday from a 660 mile road trip, temp was between 80-85 degrees with mild humidity, double lane hiway so speed varied between 70 - 75mph, 3200 RPM. Car ran excellent and the temp was consistent.
It was fine on the around town cruzing as well but there was no extended idle time to worry about.
The 383 is pretty much stock with a few bolt ons.
The 14 - 15 MPG is a bit of an annoyance though.
