I recently took mine out for a 100 mile trip (200 miles round trip) to test my mileage under different throttle conditions, on the way out I drove between 70-80 mph (as traffic allowed). Now mind you I have a bit of a heavy foot and two 4 barrel carbs, and I run top grade 91 octane. On the way out 100 miles I averaged 12-13 mpg.

Coming back I dropped the speeds and was careful with my foot, ran between 65-70 mph for about 60 miles and averaged 13 mpg. But here's the surprise!, when I dropped the speed down and stayed at 50 mph for the remaining 40 miles I averaged over 40 miles to the gallon!

Course that's not making any allowances for the tow truck's mileage……………

Seriously Don, stop trying to analyze everything, drive the car and have fun!

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