The old school way is to jack it up, and see how many driveshaft revolutions it takes to make one full tire revolution. Example <3 = 2.73 gear. Almost 4 = 3.73 gear.

 

Mine in 1967 was a 3.08 single trac. Sure wish I had it back............

 

Look on the front of the passenger axle tube, there should be some stamped numbers there that will decode what gears were in it from the factory. My guess would be 3:08 gears.

 

Thx to all.

 

Checking numbers is one way, but someone may have changed the gears. The only real way to know is remove the diff cover, count the teeth on the pinion gear, (middle gear) count the teeth on the ring gear, (big ring). Then divide the ring gear teeth number by the pinion gear teeth number. Your gear ratio will magically appear in your calculator.

 

Mine is also 3:08 . 327 4speed 67RS

 

My still stock 350SS/RS drivetrain is an M-20, 3.31 posi- and right at a stock height back then of 25.3" to 25.5" tall tires.

327, 4-speed, I figure 3.36's.

pdq67