High Speed rear end gears

[jcrow]

Does anyone make high speed rear end gears that will fit a 1940 80 Series? Thanks for any ideas. Johnny

[1939_Buick]

A common question for straight 8 Buick's

Quick answer: probably not.

Relatively easy for series 40 & 60 using parts up to mid 50's.

But 80 & 90 diff's are different so more work needed. They are and not the same as series 40 & 60.

The ring & pinion part number is used for only 1940 S80, 1941 S90 [ratio 46:11]

Over the weekend will do more research on the housing & axle part numbers

Look here

http://forums.aaca.org/f165/swapping-rear-ends-354186.html

http://forums.aaca.org/f165/1941-crown-pinion-change-351659.html

Others

http://forums.aaca.org/f115/37-buick-90-a-356435.html

http://forums.aaca.org/f115/47-roadmaster-rear-axle-ratio-136421.html

http://forums.aaca.org/f115/ring-pinion-183118.html

http://forums.aaca.org/f162/ring-pinion-interchange-239662.html

http://forums.aaca.org/f165/series-40-60-ring-pinion-225553.html

http://forums.aaca.org/f117/4-10-ring-pinion-whole-pumpkin-311630.html

http://forums.aaca.org/f119/ring-gear-pinion-sets-289809.html

http://forums.aaca.org/f115/40s-rearend-gears-135370.html

http://forums.aaca.org/f165/40-ring-pinion-236959.html

http://www.jalopyjournal.com/forum/showthread.php?t=319814 [good detail]

http://www.teambuick.com/forums/showthread.php?20920-rear-gear-swap

http://forums.aaca.org/f165/37-special-diff-gears-upgrade-344831.html

Edited August 10, 2013 by 1939_buick
more links. Added ratio. Rernoved 1942 (see edit history)

[critterpainter]

Have you thought about having an overdrive installed. There are some specialty places that can install them in your torque tube.

[CHAD THOMAS]

Curious how fast you plan on driving your Buick? The gearing in my is fine around here, will keep up on the interstate if need be without being too busy.

[jcrow]

I appreciate everyone's help so far. Whatever gears the car has (1940 80 series convertible sedan) it is spinning too fast at 50 mph. I just restored the engine (car was originally restored around a 60k original engine) and the last thing that I need to do is strain the new engine. I do like to tour with my cars (Caravans, etc) so would like get it to run comfortably at freeway speeds. Price is not a major consideration. Thanks for the help and questions.

[FLYER15015]

jcrow,

Keep after it for the sake of those that follow.

I'm in the same position that you are but with a '40 series 90.

I've just begun my quest for a taller rear gear too, and the big series cars are different in many ways.

As a last resort you could consider converting over to an open drive line, which opens up a lot of Buick and other GM models rear ends. Nobody would know if you don't place mirrors under your car at the shows.

Mike in Colorado

[CHAD THOMAS]

I guess I need to check my spare axle and see what is in it. It maybe of some use to you. Came from a 41 Series 90 sedan. I understand your car having lower gears due to weight. My car is very relaxed at 50

[1939_Buick]

The ring & pinion part number is used for only 1940 S80, 1941 S90 & 1942 S90 (up to frame ??) [46:11 ratio 4.182]

ring 5.503 1302177

pinion 5.503 1313200

Axle shaft is common to 1938 1939 1940 series 80 & 90 and 1941 series 90

group 5.420 part 1394560 Shaft, rear axle right

group 5.420 part 1394561 Shaft, rear axle left

In the Torqetube magazine Vol XV Issue 6 ( www.1937and1938Buicks.com ) is an article where a person with a 1937 Limited (S90) replaced the diff with 1955 assembly, third member & torque tube (ratio 3.4:1)

Edited July 31, 2013 by 1939_buick (see edit history)

[1939_Buick]

Another link: http://forums.aaca.org/f165/37-special-diff-gears-upgrade-344831.html

Have yet to find any information on Series 80 & 90's