Thread: Merc OD
View Single Post
Old 12-30-2023, 05:12 PM   #46
38 coupe
Senior Member
 
38 coupe's Avatar
 
Join Date: May 2010
Location: South Texas
Posts: 1,701
Default Re: Merc OD

Sponsored Links (Register now to hide all advertisements)
Glad to hear of the successful drive.

The factory 1950 Mercury rear axle ratio is 4.27 to 1. Combine that with the overdrive ratio of 0.7 to 1 and the overall ratio is 2.99 revolution of the crankshaft for every revolution of the rear wheels. If you have 28 inch tall tires you are running less than 2400 rpm at 66 miles per hour. Your engine is just fine at that speed. Unless there is a balance problem your engine should be happy to around 2700 rpm, which is about 75 mph with your combination.
38 coupe is offline   Reply With Quote