ImprezaObsNick
07-24-2011, 09:47 PM
I'm not at all taking credit for this post! I have been looking for these answers for my Hybrid WRX and didn't see any posts about this kind of issue on D.i SOOOO i'll link and quote what I found on Nasioc.
http://forums.nasioc.com/forums/showthread.php?t=1412230
WRX-17
NASIOC Supporter
Member#: 98725
Join Date: Oct 2005
Chapter/Region: RMIC
Location: FoCo, CO
Vehicle:
05 WRX
Aspen White
FAQ: STi 6MT Swap into a WRX
FAQ: USDM STi 6MT Swap into a WRX
Well I thought I would finally try to give back to nasioc by sharing this with everyone in the hope that others would appreciate a simplified page about the swap.
Front Differentials:
02-07 WRX: open
04 STi: “SureTrac” LSD
05-07 STi: “Helical” LSD
Rear Differentials: R160, R180
These were originally used in the Datsun 510, 610 and other IRS Datsuns. The "R" stands for Fuji Heavy Industries. The R180 was used in the front axle of Datsun 4x4 trucks (720, etc). The number represents the ring gear size in millimeters.
R160 – 52lbs. WRX rear differential. It has a viscous LSD which is no better than an open differential since the unit is so tiny in this diff.
02-05 have a 3.54 gear ratio
06-07 have a 3.70 gear ratio
R160’s on 2.2L Legacy/Impreza’s have a 3.9 gear ratio
R180 – 64lbs. STi rear differential. It has a mechanical clutch type LSD.
04-05 R180’s have a 3.90 gear ratio
06-07 R180’s have a 3.54 gear ratio
Center Differentials:
02-07 WRX: Viscous coupling type
02-05 has a 1.1:1 gear ratio
06-07 has a 1:1 gear ratio
04-07 STi: DCCD (Driver Controlled Center Differential)
04-05 has a 1:1 gear ratio
06-07 has a 1.1:1 gear ratio
Do I need different front axles?
02-early 04 WRXs have female axles and need to use stubs that go inside the tranny. Late 04-07 WRXs use male ended axles that slide inside the front differential so there is no need for stubs. For the female axles, you need axle stubs, circlips, and seals to reuse the WRX axles (check out the seal differences link for part numbers). You can use the stubs from your 5MT. For the male ended axles, they just slide right into place with the correct seals and circlips. 04 STi front axles will work too.
Will my WRX clutch and flywheel work in a 6speed?
-Yes. The diameter of the WRX flywheel is smaller (230mm compared to 240mm) than the STi flywheel. The bell housing on the 5speed is also smaller. There is less surface area with the 5speed compared to the 6speed but is not a huge difference. There are no issues with running a 5MT clutch and flywheel in a 6MT. See post #24
Will my WRX starter motor work in the 6MT?
-Yes. WRX and STi starter motors are the same part number.
What if I don’t have/use a DCCD (Driver Controlled Center Differential) controller?
-The DCCD defaults to open mode which is a 35% front/65% rear power routing in 04-05 and 41/59 in 06-07. There isn’t anything “wrong” with this, but if you are running the R160 with the 3.90 Ring and Pinion the compromise is in an even shorter life of the differential since more power is being routed to the rear. This of course all depends on the driver as some have a knack for blowing parts out even at stock power levels. The options for a controller are: Spiider’s (DCCDPro.com), Neetronics.com, RocketRally.com…
Is there a strength difference between the WRX and STi drive shafts and axles?
Subaru’s use 2-piece drive shafts. The WRX drive shafts are 2.5” longer than the STi and they use a ball-joint whereas an STi driveshaft uses a universal joint which is stronger. The STi axles are stronger because of a larger diameter bar and beefier CV joints.
What are my options for doing a 6MT swap?
-There are really only 2 routes:
1) Thanks to Bayley for pioneering this route so a 6MT swap was actually feasible for most. This parts list includes:
• Tranny
• 6MT clutch fork
• Auto driveshaft or STi ds and enlarge the holes on the ds and yoke or switch the yoke on the R160 to the bigger R180 yoke if you can get one.
• Put 3.90 gears in your R160 Differential (if using an 06-07 tranny with an 02-05 R160 there is no need to change anything with the differential)
• Reuse your WRX axles
• STi shifter linkage
• 6MT tranny mount (5MT and 6MT mounts are different)
• DCCD controller (optional, but recommended)
2) Here’s the expensive but stronger way:
• Tranny
• 6MT clutch fork
• STi driveshaft
• R180 differential
• STi axles
• STi hubs
• STi knuckles
• STi Brembos (calipers, rotors, pads) technically you only need the rear
• STi strut assembly (05+ knuckles)
• STi shifter linkage
• 6MT tranny mount
• DCCD controller
All of these threads helped me out:
Swapping in a USDM STi 6-speed for under $3000 (my story – long)
2006 STi Transmission Differences
Master swap list for 04-07 Sti 6 speed into WRX
Master 6 Speed Transmission Decoder Ring
Axle seal differences in recent years
Trasnmission FAQ
For those wanting to make their own DCCD controller
WRX 6MT swap (part 1)
WRX 6MT swap (part 2)
I created this because the information I found was spread out over many threads. I did a lot of searching for this and aftering reading it you should have a pretty good idea of what is involved in a 6MT swap. I will do my best to keep this updated whenever I find any new info or if anyone needs more clarification on something let me know and I can add more detail. If there is an error please send me a PM with the facts.
I will slowly be updating bits n pieces of information in the thread that will also help.
Enjoy D.i! :eyebrows:
http://forums.nasioc.com/forums/showthread.php?t=1412230
WRX-17
NASIOC Supporter
Member#: 98725
Join Date: Oct 2005
Chapter/Region: RMIC
Location: FoCo, CO
Vehicle:
05 WRX
Aspen White
FAQ: STi 6MT Swap into a WRX
FAQ: USDM STi 6MT Swap into a WRX
Well I thought I would finally try to give back to nasioc by sharing this with everyone in the hope that others would appreciate a simplified page about the swap.
Front Differentials:
02-07 WRX: open
04 STi: “SureTrac” LSD
05-07 STi: “Helical” LSD
Rear Differentials: R160, R180
These were originally used in the Datsun 510, 610 and other IRS Datsuns. The "R" stands for Fuji Heavy Industries. The R180 was used in the front axle of Datsun 4x4 trucks (720, etc). The number represents the ring gear size in millimeters.
R160 – 52lbs. WRX rear differential. It has a viscous LSD which is no better than an open differential since the unit is so tiny in this diff.
02-05 have a 3.54 gear ratio
06-07 have a 3.70 gear ratio
R160’s on 2.2L Legacy/Impreza’s have a 3.9 gear ratio
R180 – 64lbs. STi rear differential. It has a mechanical clutch type LSD.
04-05 R180’s have a 3.90 gear ratio
06-07 R180’s have a 3.54 gear ratio
Center Differentials:
02-07 WRX: Viscous coupling type
02-05 has a 1.1:1 gear ratio
06-07 has a 1:1 gear ratio
04-07 STi: DCCD (Driver Controlled Center Differential)
04-05 has a 1:1 gear ratio
06-07 has a 1.1:1 gear ratio
Do I need different front axles?
02-early 04 WRXs have female axles and need to use stubs that go inside the tranny. Late 04-07 WRXs use male ended axles that slide inside the front differential so there is no need for stubs. For the female axles, you need axle stubs, circlips, and seals to reuse the WRX axles (check out the seal differences link for part numbers). You can use the stubs from your 5MT. For the male ended axles, they just slide right into place with the correct seals and circlips. 04 STi front axles will work too.
Will my WRX clutch and flywheel work in a 6speed?
-Yes. The diameter of the WRX flywheel is smaller (230mm compared to 240mm) than the STi flywheel. The bell housing on the 5speed is also smaller. There is less surface area with the 5speed compared to the 6speed but is not a huge difference. There are no issues with running a 5MT clutch and flywheel in a 6MT. See post #24
Will my WRX starter motor work in the 6MT?
-Yes. WRX and STi starter motors are the same part number.
What if I don’t have/use a DCCD (Driver Controlled Center Differential) controller?
-The DCCD defaults to open mode which is a 35% front/65% rear power routing in 04-05 and 41/59 in 06-07. There isn’t anything “wrong” with this, but if you are running the R160 with the 3.90 Ring and Pinion the compromise is in an even shorter life of the differential since more power is being routed to the rear. This of course all depends on the driver as some have a knack for blowing parts out even at stock power levels. The options for a controller are: Spiider’s (DCCDPro.com), Neetronics.com, RocketRally.com…
Is there a strength difference between the WRX and STi drive shafts and axles?
Subaru’s use 2-piece drive shafts. The WRX drive shafts are 2.5” longer than the STi and they use a ball-joint whereas an STi driveshaft uses a universal joint which is stronger. The STi axles are stronger because of a larger diameter bar and beefier CV joints.
What are my options for doing a 6MT swap?
-There are really only 2 routes:
1) Thanks to Bayley for pioneering this route so a 6MT swap was actually feasible for most. This parts list includes:
• Tranny
• 6MT clutch fork
• Auto driveshaft or STi ds and enlarge the holes on the ds and yoke or switch the yoke on the R160 to the bigger R180 yoke if you can get one.
• Put 3.90 gears in your R160 Differential (if using an 06-07 tranny with an 02-05 R160 there is no need to change anything with the differential)
• Reuse your WRX axles
• STi shifter linkage
• 6MT tranny mount (5MT and 6MT mounts are different)
• DCCD controller (optional, but recommended)
2) Here’s the expensive but stronger way:
• Tranny
• 6MT clutch fork
• STi driveshaft
• R180 differential
• STi axles
• STi hubs
• STi knuckles
• STi Brembos (calipers, rotors, pads) technically you only need the rear
• STi strut assembly (05+ knuckles)
• STi shifter linkage
• 6MT tranny mount
• DCCD controller
All of these threads helped me out:
Swapping in a USDM STi 6-speed for under $3000 (my story – long)
2006 STi Transmission Differences
Master swap list for 04-07 Sti 6 speed into WRX
Master 6 Speed Transmission Decoder Ring
Axle seal differences in recent years
Trasnmission FAQ
For those wanting to make their own DCCD controller
WRX 6MT swap (part 1)
WRX 6MT swap (part 2)
I created this because the information I found was spread out over many threads. I did a lot of searching for this and aftering reading it you should have a pretty good idea of what is involved in a 6MT swap. I will do my best to keep this updated whenever I find any new info or if anyone needs more clarification on something let me know and I can add more detail. If there is an error please send me a PM with the facts.
I will slowly be updating bits n pieces of information in the thread that will also help.
Enjoy D.i! :eyebrows: