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| Gearbox Swaps | |
| Types: 56 | 60 | 63 | 71 | 90 | R30 | |
| Transmission Swaps | |
| Identification | |
| 5-Speeds | F5C56A | Stumpy | |
| 6-speed | |
| Toyota 5-speed | |
| Manual/Auto conversion | |
| more: Transmission Modifications |
6-speed transmission gives you two (count 'em 2) overdrive gears. Or some have a close ratio direct-5th with overdrive, which is better for performance. 6-speeds can be modified to fit Datsun 1200. Just cut the bellhousing and weld on a fragment of A-series bell housing, then machine the input shaft smaller.
Contents |
Aisin AZ6
6-speed with A-series bell grafted on
Nissan R30A 81-series gearset 285 Nm R31A 85-series gearset 450 Nm
The basic Aisin AZ6 gearbox was made in several versions, with front cases for these engines:
- Nissan FS6R30A (source: Nissan pickup 2004-)
- Nissan FS6R31A for SR20DET (source: S15)
- Nissan FS6R31A for VQ35 (source: Z33 "350Z")
- Nissan FS6R92A for VQ35 (source: G35) 130 lbs weight
- Nissan FS6R92A for SR20 (source: S15)
- Mazda Renesys (RX8 rotary)
- Mazda Y16M-D F & B (1999-2005 MX-5)
- Toyota J160 for 1G & 3S (E10 Toyota Altezza/Lexus IS200)
- Toyota 86/Scion FR-S
- Subaru BRZ
A limited run was produced of custom front cases for Toyota T-50 bellhousing, so with this gearbox a Dellow kit might work to mate it to the A-series engine.
But other wise, use the Cut-n-Shut method.
FS6R31A
Nissan sells brand-new 350Z 6-speeds for $1700-$2000ᴳ (MSRP of $2300, so shop around. Your local Nissan dealer may charge the full price, but other dealers are selling for under $1800 as of June 2022).
Nissan RWD six-speed is plentiful in wrecking yards and inexpensive new ($1800) or used ($900). Use an adapter plate and bob's your uncle. Reportedly 3x stronger than an SR20DET 5-speed. It is a true direct-fifth gearbox + overdrive.
- Z33 "350Z" 2003-
- 2005- six-cylinder Frontier, Xterra, Pathfinder
FS6R31A F5C56A 1st 3.794 3.757 2nd 2.324 2.374 3rd 1.624 1.659 4th 1.271 1.291 5th 1.000 1.000 6th 0.794 -- Rev 3.446 4.046
S15 6-speed
The 1999-2002 Nissan Silvia S15 Strawberry with SR20DE/SR20DET had an optional close-ratio 5-speed + overdrive (6 forward speeds total). In AUS, the six-speed was in the Nissan 200SX Spec-R model.
S15 modified; A-series bell grafted on
- FS6R92A
- only 16kg heavier than a standard 1200 4spd
- Close ratio 1-5, with overdrive 6th. It is perhaps the best ratios for an A-series engine
Gear Ratio
Comparison with A-series 5-speeds
.model. First. Second Third. Fourth Fifth. Sixth. Reverse FS6R92A 3.6264 2.2000 1.5412 1.2132 1.0000 0.7674 F5C56A. 3.757. 2.374. 1.659. 1.254. 1.0000 ------ 4.04 F5C56Ac 2.676. 1.691. 1.398. 1.181. 1.0000 ------ 2.877 FS5W60L 3.513. 2.170. 1.378. 1.0000 0.846. ------ 3.764 FS5W63A 3.382. 2.013. 1.312. 1.0000 0.854. ------ 3.57
Comparison with S14 5-speed
.model. First. Second Third. Fourth Fifth. Sixth. Reverse FS6R92A 3.6264 2.2000 1.5412 1.2132 1.0000 0.7674
Comparision of various Aisin AZ6 models:
FS6R92A First. Second Third. Fourth Fifth Sixth. Silvia. 3.6264 2.2000 1.5412 1.2132 1.000 0.7674 RX8.... 3.760. 2.269. 1.645. 1.187. 1.000 0.843. MX5 99. 3.760. 2.269. 1.645. 1.257. 1.000 0.843. RS200.. 3.874. 2.175. 1.484. 1.223. 1.000 0.869.
Pilot Bushing
S15 5-speed FS6R92A
- 32202-B9500 BUSHING-CRANKSHAFT
- used on L, Z, VG, VQ, SR, KA, and CD engines (same as 71C bushing)
- Pilot Bushing Inside Diameter: 0.626 to .6300 inch (Length: .689")
- Pilot Bushing Outside Diameter: .814 to .815"
Since this is much larger in diameter than the A-series, machining is needed.
A-series crankshaft bore is for a bushing with 0.671" O.D., length .723"
- The FS6R92A input shaft end can be turned down to ~.671 O.D.
- Could the A-series crank pilot hole be bored out to .814" so the 71-Series bush can be fitted?
Input shaft end turned down to smaller diameter
Clutch Disc
FS6R92A clutch disc [all 240mm]
- 30100-85F00 9901-0011
- 30100-85F14 0011-
- Spline O.D.: 1'
- Spline: 24 teeth
There is an A-series clutch disc that is 1' x 24T: 30100-K0500.
Input Shaft Length
How far does the FS6R92A input shaft extend past the transmission face?
- 5-speed: about 17mm past the flange
- 6-speed: about 10mm inside the flange
Speedometer
S15 6-speed does not have a speedometer gear.
Clutch Release
How to connect up the clutch?
Gearshift Location
Comparision of Nissan 6-speed with long-5-speed and short 4-speed. The location of the shifter is close to the location of stumpy gearbox shifter.
Rear Crossmember
Use a generic crossmember to fit a 6-speed.
Propeller Shaft
The 6-speed overall length is greater than a stumpy gearbox, but not as long as a a longtail Nissan transmission.
6-speed vs 71C long vs 71B long vs F4W63 stumpy
Toyota J160
A limited run was produced of custom front cases for Toyota T-50 bellhousing, so with this gearbox a Dellow kit might work to mate it to the A-series engine.
Aisin AZ6 with custom front case for T-50 removable bell housing. A custom input shaft is used.
Toyota J160 dimensions
overall length: 740mm (not counting shifter) * including shifter: 870mm length front case: 270mm length gear case: 190mm length tail housing: 28mm