Hudson 6 Bolt Pumpkins

allan

here's a good discussion topic:  I have acquired a 6 bolt (pre 1938) pumpkin that I would like to put in place of my 4:11 in a 1940.  Will it fit?  Assuming I plan to drive like I'm driving an old car, will it hold up?

allan

actually this should be 6-bolt ring gears.

allan

The pumpkin setup I acquired is a 3-5/9.  it's obviously for an earlier car, but when I look in the parts book, that ratio was for a "service" vehicle.  I don't know what that means.  I'll have to check axle diameters further when the weather breaks.  But I am hoping to run that ratio behind an overdrive to make a 212CID road car.  Could be a pretty cool set up for going the distance,  all be it under powered - I can live with that!

Jon B

Allan, you might give Nelson a ring, he might know.

allan

you may be right Ken, but who wants to run 60 mph?  I want to run 75 giving me 2200 RPM - right in the power curve (on flat ground that is).  Lots to think about in the coming months.

Park_W

Allan, you'd be over-geared with the 3 5/9 and OD.  Tried it on my Hornet when I put the OD in it, and it was too "tall."  As mentioned above, you'd be considerably below the optimum RPM.  I'd run it with the 3 5/9 and no OD.

allan

what is the final drive with overdrive and a 4.11 vs. 4.59 as the factory would have done?

Jon B

Isn't that a simple matter of calculation?  4.11 rotations after an overdrive ratio of .7 (I think).  It would be 4.11 rotations at the rear axle in conventional 3rd gear (1:1 ratio).  Multiply that by .7 and you get 2.88 rotations per revolution of the engine.  It would be 3.21 for the 4-5/9" (standard) ring and pinion, in OD.  And, of course, 4.59 in conventional 3rd with no overdrive.  Going in the opposite direction, if you glommed onto a 3-5/9 gearset, your rear axle would turn 2.128 times for every revolution of the engine.

Keep in mind that math is not my strongest suit.

allan

Awesome guys, thanks.