Obviously from the results listed by others, we can surmise that “a very well tuned engine” running like new, is likely to give impressive performance.
Both Michel and I have 280SL’s that are running well, but I dare say we could both benefit from “a professional tune up”.
Below are the results of our 1600 mile true comparison round trip from Montreal to Blacklick. We consider this run to be about 95% highway at a conservative 60 mph,and "top down" 98% of the time.
Both cars were refuelled at the same service stations en route.
Michel’s 280 with automatic VS Tom’s 280 automatic & Borg-
Warner Overdrive
Date Distance Fuel gal. MPG Fuel gal. MPG
07/26 292.4 mi. 16.274 17.97 14.25 20.51
07/17 312.7 16.322 19.16 14.50 21.56
07/29 268.6 16.528 16.25 13.93 19.28
07/30 291.7 16.850 17.31 13.46 21.67
07/31 367.6 19.910 18.46 16.51 22.27
Total 1533.0 85.884 72.83
Averages: Michel’s 17.85 mpg VS Tom’s 21.05 mpg Thus we can confirm, for the identical run, a "net fuel economy of 17.9 %" that was achieved with the use of Overdrive, slightly more than I had previously reported in my update, under “Overdrive for Comfort and Economy”. Sincerely; WTF
W.T.Forsythe
