Something I put together back in 2007 over on Nasioc. I figured it would be beneficial to post it here as well for those members that have not seen it. Ok, so I have read the FAQ's, read lots of threads and I would like to compile a list of what all is needed for the various years of Sti transmissions to be swapped into the 02-05 WRX. What I really have not been able to find is what is needed when you throw JDM transmissions into the mix. Here is what my understanding is so far. PLEASE feel free to jump in and add your knowledge. I know there is a large number of swaps that have been done with all kinds of year and there are some differences with each. I just think with a superior design the Sti transmission is a great option for those needing something that can hold some more power. While it may not be indestructible, it is still a HUGE improvement over the WRX 5 speed glass box. Other upgrades include the RA gear set for mild power, MTR gears, Kaz gears and of course PPG and M-Factory gears. There are a fantastic selection of products not only for the WRX 5 speed but also for the Sti 6 speed available from several different companies . So here goes: 04 USDM Sti 6 speed: -transmission -driveshaft from an automatic or from Sti with a yolk for a wrx -3.90 R&P gear to replace the 3.54 in the WRX OR -R180 rear differential and Sti hubs, rotors, brakes and axles* -6 speed shifter and assembly**** -front axles and hubs can be reused provided the transmission still has the axle stubs in it. -DCCD controller optional but recommended** -6-speed clutch fork and slave cylinder? -5speed or 6 speed flywheel and clutch 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 0.971 6th - 0.756 04 JDM Sti 6 speed: -transmission -driveshaft again -3.90 R&P gear to replace the 3.54 in the WRX OR -R180 rear differential and Sti hubs, rotors, brakes and axles* -6 speed shifter and assembly**** -front axles can be reused if it has stubs in the transmission? -some seem to be DCCD and others non-DCCD with Viscous LSD -6-speed clutch fork and slave cylinder? -5 speed or 6 speed clutch and flywheel 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 1.062 6th - 0.842 Final - 3.900 05 USDM Sti 6 speed: -transmission -driveshaft -3.90 R&P gear to replace the 3.54 in the WRX OR -R180 rear differential and Sti hubs, rotors, brakes and axles* -6 speed shifter and assembly**** -hubs or Stubs? Not clear on this one for the front but it seems there is extra that needs to be done with an 05*** -DCCD controller optional but recommended** -6-speed clutch fork and slave cylinder? -5 speed or 6 speed clutch and flywheel 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 0.971 6th - 0.756 05 JDM Sti 6 speed: -transmission -driveshaft -3.90 R&P gear to replace the 3.54 in the WRX OR -R180 rear differential and Sti hubs, rotors, brakes and axles* -6 speed shifter and assembly**** -hubs or Stubs? Possible using 03-04 stubs could work with the correct clip and seal like the 2006 tranny and then reuse wrx axles*** -Again not clear, but seems some come without DCCD** -6-speed clutch fork and slave cylinder? -5 speed or 6 speed clutch and flywheel 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 1.062 6th - 0.842 Final - 3.900 06 USDM Sti 6 speed: -transmission -driveshaft -Stock R160 can be used without changing the gear ratio due to change in 06 that makes the ceneter diff a 1.1:1 vs the old 1.0:1 -stock rear axles can be used on rear due to no need to change the rear diff -front...04 Sti Axle stubs can be ordered along with seals and clips that retains the WRX front Axles, hubs, etc? Special seals are needed. Axle Stub Part Number: 38415AA110 Circlip Part Number: 805329010 from Wrinkleboi's thread about this*** -6 speed shifter and assembly**** -DCCD controller optional** -6-speed clutch fork and slave cylinder? -5 speed and 6 speed clutch and flywheel 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 0.971 6th - 0.756 06 JDM Sti 6 speed: into wrx -transmission -driveshaft -6 speed shifter and assembly**** -6-speed clutch fork and slave cylinder for 2007 sti R160 rear diff (02-05 wrx) 6 speed clutch and flywheel Circlips from 2004 sti, oil seals and axle stubs 1st - 3.636 2nd - 2.375 3rd - 1.761 4th - 1.346 5th - 1.062 6th - 0.842 Final - 3.900 07 USDM Sti 6 speed: into wrx -transmission -driveshaft -6 speed shifter and assembly**** -6-speed clutch fork and slave cylinder for 2007 sti R160 rear diff (02-05 wrx) 6 speed clutch and flywheel Circlips from 2004 sti, oil seals and axle stubs 1st: 3.636 2nd: 2.375 3rd: 1.521 4th:1.137 5th:0.971 6th: 0.756 reverse - 3.545 final drive ratio - 3.90 JDM 07 Sti 6 speed -transmission -driveshaft -6 speed shifter and assembly**** -6-speed clutch fork and slave cylinder? -no clue -no clue -no clue unknown ratios. *For those wanting to use the R180 but not switch out the hubs, Apparently driveshaftshop.com offers custom axles (pricey) that allow you to retain the wrx hubs while using the R180 rear end. ** DCCD controller options...seems a member on here Spider? is making one for around $150, others go up from there. Without going to an Sti ECU it does not appear to be able to be used as a fully automatic setting, but Spiider's and the Neetronic units seem to get close. Then there is the 100% lock up with a toggle switch. I am unsure as to how soon this could kill the DCCD, but who knows it could last forever! Some sites with controllers: www.neetronics.com www.gems.co.uk www.rocketrally.com www.motec.com www.dccdpro.com *** There may be a difference between the 05 axles and the 02-04 axles on the WRX. There may have been a change to the axle and some 05 wrx might be able to use their stock axles. I have not verified this, just read some threads suggesting it. ****The shifter boot is suggested, but not necessarily an absolute must. The old shift boot can be reused with some modification and work. Shift knob is the same, it can be reused if necessary, but not the best option. Thread about this located here see post #66. Parts and numbers for some of the parts: 32000-AJ350 2007 STi transmission 805329010 Circlips need 2 38415AA110 stubs need 2 806730041 oil seal Left and right side are different 806730042 oil seal Left and right are different C1010FE004 short shifter 35046FE010 -shifter joint 633046020-spring pin Thanks to WJM for the part numbers
i've read somewhere in the last 2 months, that you can install a STI r180 rear diff to match whatever sti 6 speed you are putting in and then (this gets a bit foggy) get legacy of some year half shafts, disassemble them, mate the outer portion that goes to your rear hubs with the inner portion from the legacy that goes to your new r180 diff. thus keeping your wrx hubs, brakes, struts etc and using a r180 STI rear diff that matches your STI trans. another option is to spend 1100+ dollars with driveshaft shop and buy custom axles that do the same thing. i've heard though that the axles have issues, dont last and/or are noisy.http://forums.nasioc.com/forums/showthread.php?t=1201152&page=15
I think Integroid said he had over $600 in axles doing the Legacy conversion. While it is a good bit more, you can get some custom axles that would probably hold up better if high hp is a concern. Another option is to build the R160 up or get 04 Sti 5x100 hubs. But if the car is going to see some abuse or track time switching out to the Sti hubs and the R180 is beneficial.
from what i understand, the WRX front knuckles/hubs are really an issue if you do track days and/or race. an upgrade to 05+ STI front hubs helps here or at one time you could get the 6gun stuff or there's some ultra expensive options available from Turn In Concepts who second source this stuff: i asked about this, seems like it was more than 10k to get this set up complete.
This is only for Legacys. You have to buy the rear axles from a 2007+ Spec B to mate with the R180 Rear Diff and the rear hub. NO ONE makes remans and no junk yard has them so they are $300 ea from Subaru.
Its not quite that bad, those parts are built by MSI. I'm looking forward to getting my Front Uprights (pictured above), Rear Subframe, and Spherical Bearings for the front control arm.