Joe, this is the combination I have: '49 3100, '56 235 (.30 over) with "848 head" (the last 3 #'s of the head ID casting indicating a slightly higher compression), '55 3 sp+od, '57 truck 3.90 rear. My former torque tube set-up-as-is when I purchased the truck imploded one day on the way to work, a 3 mile in town commute, so I did the changeover to the open driveline set-up by burning off the old pivot-mounted spring perch assemblies and replacing them with Buffalo spring perches and tube shock mounts for the rear and front (bye-bye knee action shocks). The '57 3.90 rear is from a truck, I pulled the pumpkin from a bone yard and after having it rebuilt by a man who had done "100's of these" with new bearings and crush sleeve, I measured the length of open driveshaft needed and I was good to go. The pumpkin is one of those plug-ins that fit the 10 bolt '49 axle perfectly. The overdrive for '55 is .70, so .7 X 3.9= 2.73; your final drive ratio in overdrive. I now can drive at 65mph @ around 2000rpm's in OD with my 215 85R 16 Michelin TRUCK TIRES,(30" tall). I don't have or seem to need any of that 'kick-down stuff' for the OD, I wired my solenoid to a two pole, push-pull switch in the never used throttle hole, complete with the "T" knob, also a light wired into my on-off switch from radio shack located in the left radio blank out hole to remind me NOT to start out in 1st OD! This is a note to self: NEVER start out in 1st OD, if you've ever been inside this tranny the reason is self evident. I've rebuilt one and am presently rebuilding another so I know of what I speak. I'm still 3-on-the-tree for a strange reason...people always ask me how I can shift from Park to Drive without the letters on the column, they think it's an automatic and many don't know what you're talking about when you say that "...it's a three speed pattern, it's just on it's side." Some would think this is a great combination, just as many are "living in 1949" which is cool but your're wound out with that 4.11 rear at 50, she'll be shouting at you at 55mph. Then there's the other side of the coin for those who desire chirping a little rubber in all four gears...for any of us that want to go that way we have to think about decreasing the weight of rotating mass (Aluminum flywheel, maybe Al driveshaft, lightweight wheels with low profile car tires,etc.) You have to consider a vee ate (misspelling intentional) and so on. I see this is your first post so may I extend a welcome to you from all of us with all kinds of goals for our vehicles. I've got a lot of info on the old od's if you want to contact me, right now my email carrier is all afoul. .....I got ten forward gears and a georgia overdrive, I'm taking little white pills and my eyes are open wide, There's a speed zone ahead allright, I been passin' everything in site, Six days on the road and I'm gonna make it home tonight... Cosmo
