auto to 4 spd OD swap

1965 Abody 904 to A833 OD swap info

Flywheel

1963-67 flywheel must be used with a 1963-67 crank.

64-67 273 size 9.5 in. Part number 2463256 122 tooth ring

Clutch

A10” clutch can be used with special bolts.
The 10 1/4" slant 6 van clutch assembly will fit the early 273 flywheel.

Pedal and Fork

On the original 1964-66 A-833 cars, everything between the driver's left foot and the clutch release bearing (AKA the throw out bearing) is the exact same setup as the 1963-1966 slant six A-903 three speed cars. This includes the z-bar (torque shaft), clutch fork and push rod. On later A-bodies and other platforms, you may need to "mix and match" linkage parts. Be aware that the early bell housing used the small slant six clutch fork and the slant six z-bar needs to be used with it to get the correct movement on the release bearing. The later Overdrive bell housings used the longer V8 clutch fork.

Hydraulic Clutch

For those of you wanting to convert to a hydraulic clutch and use stock fork configuration DO NOT use a 5/8 " bore master cylinder!
There are several slave cylinders available with long travel that will do the job if you have a master cylinder that will move enough juice. The 3/4" is the absolute minimum to use and the 13/16 or 7/8 are needed on the larger bore slave units. The 84' Jeep scrambler slave has long travel and an interesting mounting flange. It has a 7/8 bore though so plan on using a large master cyl.

I am 99.9% certain now that the master cyl (13/16 bore) and slave cyl from a 1985 Jeep CJ or Scrambler (7/8 bore) will do the trick. The slave is at O'Reilly for $18.19 and the master at advance is about $57. Part #s CSA11956 and 39738 respectively.... Have to fab a bracket for the slave and get your flex line figured but no big deal. The push rod will be rather simple 3/8 bolt or all thread cut and rounded at proper length. Just figure out your pedal travel and geometry and it's a done deal.

Transmission

get an 833 OD out of a '75+ A body or an F body, that will have the "right" tail shaft and shifter mounting location.

1975 thru 1987 Overdrive 3.09:1 - 1.67:1 - 1:1 - 0.73:1 (Trucks used a 0.71:1 fourth)

A bell with a 4.80" opening will work if you have the input bearing retainer on the OD turned down, or you can also buy an "adapter" input bearing retainer that has the larger 4.16" bolt pattern and a 4.80" outer diameter.


Here are the start-off ratio calculations: (2.47 x 3.91 = 9.65 start-off ratio) and (2.47 x 3.55 = 8.77 . . .)
Note: as a general "rule of thumb" a 10 to 1 start-off ratio is pretty good for a "street - strip" Slant Six

Drive shaft




Floor Pan