But that would involve changing over to an open drive shaft and ultimately the transmission, amongst other major modifications. Changing your rig over to a 3.54:1 ratio on the rear will get you 70 MPH, clocking the engine at around 2500 RPM. This is the setup I have in my 54 3100 (with 4 speed). I am certain I can get 90 MPH out of my rig, if I wanted to (but don't), and still have the tach under 3K. There is no need to go to great lengths to get more speed when the 3.54:1 ratio in the rear works wonderfully. You can get the 3.54:1 ring and pinion gear set from Patricks Truck Parts. http://www.patricksantiquecars.com/ Patricks speciality is inline 6 cylinder speed parts.

Hope this helps.
Walt Williams
La Verkin, UT



Originally Posted by GMJager
Originally Posted by Whitelightning
I believe you can change out the pumpkin with a later 55-59 truck rearend (3.90) which they do make a 3.08 conversion for.

John

And if you DO swap out the pumpkin for an open drive pumpkin, you either have to weld up the pivot-style spring perches, or weld on new solid ones (something I'm working on now)

Last edited by 54Belair; 10/21/2013 11:53 PM.