Revision as of 08:43, 19 February 2015

A stumpy transmission is 26.3 inches overall length -- the same length as a Datsun 1200 transmission. The classic 'stumpy' is the 71C transmission from a Skyline, although there is a 63-series version commonly called a 'shorty'. These are the right length for a 1200, and the shifter comes up in the stock location, though obviously they are much larger around. There are 4-speed and 5-Speeds in this length.

1 63-Series
2 71-Series
- 2.1 Stumpy Transmission
- 2.2 North America
3 Interchangeability

63-Series

See: 63-Series Transmission

FS5C63A: Mid-close ratio for Z-series engines
FS5W63A: Wide ratio for L-series and A-series engines

The 5-speed is commonly called the 'dogleg' box because it has a dogleg shift pattern. However, this is not a great nickname as some other Datsun transmissions have a doglog shift pattern like the 56A 5-speed which is the same length.

NOTE: 63-series 5-speeds came in both short and long lengths. Measure to be sure which one you are getting. The long version is 31.5 inches long.

63-series 4-speeds can be identified by the removable pan on the bottom of the gearbox.

63-series 5-speeds appeared starting 1976-1/2.

A-series Engine

1976-1978 HB210 (A14 powered B210) FS5W63A

L-series Engine

1977-1979 Datsun S10 (Silvia/200SX) 5-speed
1978-1979 Datsun A10 (Stanza/Violet/510) 4-speed
1978-1979 Datsun A10 (Stanza/Violet/510) OPTION 5-speed
1968-1973 Datsun 510 4-speed F4W63
1977-1978 Datsun 610 5-speed
1972-1973 Datsun 620 USA (early with L16 engine) F4W63
Datsun 710 4-speed F4W63
Datsun 521 with L16 engine has a shorty F4W63, but with flanged output shaft

Z-series Engine

1980-1981 Datsun A10 (Stanza/Violet/510) 4-speed
1980-1981 Datsun A10 (Stanza/Violet/510) 5-speed

Other

J-series and R-series engines used F4W63, length unknown. Bell pattern differs from L-series.

F4W63L (1976-1985)

1978-up 510
Bolted on bottom pan but smooth main gear case instead of the previous ribbed design

A14 FS5W63A comparo L20B FS5W63A

Z20 5-speed

S10 L20B 5-speeed (wide ratio)
1st 3.382
2nd 2.013
3rd 1.3121
4th 1.000
5th 0.854

S110 Z20S engine (mid-close ratio)
1st 3.170
2nd 1.921
3rd 1.312
4th 1.000
5th 0.854

Do not confuse the shorty with a long-tail 63-series 5-speed:

71-Series

71-Series Transmission

Skyline DR30 (FJ20 engine with 71B)
Skyline HR30 (L24 engine with 71B)
Datsun 720 pickup USA some models (71B)

Many Datsun transmissions are longer than a Datsun 1200 gearbox, so the shifter comes up about 4 inches aft of normal.

Or you can modify a L-series "stumpy" gearbox by swapping the front case with a CA front case. Then it bolts right in, shifter in the stock location for a 1200, and stock 1200 automatic driveshaft works too.

Stumpy Transmission

The stumpy Skyline gearbox commonly refers to the R30 Skyline Australia version with the L24 (six-cylinder) engine.

Plus: fits stock shifter hole and uses stock 1200 driveshaft (automatic driveshaft)

Minus: The stumpy is the same gearbox as the 280Z 5spd (but with shorter tail), and while those are known for their durability, they don't shift as nicely and don't shift easilty above 5,000 RPM.

You need a CA20 or CA18 gearbox to get the front case which will bolt to a CA18.

To use the gearbox on a CA18, you must switch out the front section of the gearbox from a longer S13 gearbox, or a more common CA20 (e.g. 910 Bluebird Series 3) gearbox. There are conflicting reports about some of the swaps needing a different sized bearing to make this 'gearbox surgery' a success.

Beware: if the bearing doesn't fit right, the box will not last a long time. If the bearing is spot-on it can last for years behind a CA18DET.

71B front case does not require a bearing swap
71C front case needs the bearing modification
CA20E front case on a stumpy box doesn't require a different bearing
CA18DET front case on a stumpy box requires a spacer (or bearing change)

Once modified, the "stumpy" transmission bolts right into the 1200, and the gearshift lever comes up in the right place. Other CA transmissions will require you to cut a new hole in the tunnel farther back.

See:

Ca18DET and skyline 5speed install

If you wonder why people go for the stumpy 5 speed - here is a comparison photo between (from right to left) a 56 series (A12 gearbox) a 60 series (A14/A15 gearbox) and the stumpy 5 speed.