Here is the Allpar article, it concerns a 1951 DeSoto Suburban limousine which the owner bought new.

http://www.allpar.com/cars/desoto/suburban-1951.html

This is the best report I have seen on the potential long term life of a Chrysler/DeSoto flathead 6.

At the time of this writing (1975) he had put around 180,000 miles on it.

Much of it towing a trailer at speeds of 70 MPH.

He says:"Operation above 3600 RPM is avoided in the interest of long engine life, especially with such a long stroke. But continuous full throttle operation on upgrades at 3200 presents no problems".

75MPH in a DeSoto Suburban with 4:11 gears and 8.20X15 tires = 3600 RPM

3200RPM = 66 MPH

He also reports at 10,000 feet elevation, towing a trailer in the Rocky Mountains "at 70MPH the engine smooths out like a perfectly balanced turbine"

This is with a 4 3/4 stroke crankshaft, the longest stroke Chrysler made for this engine.

Last edited by Rusty O'Toole; 03/07/08 01:51 AM.
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