6MT parts shopping list
 

Ok, swap time draws nearer, and now I have to start gathering parts for the swap. This is just as much for my own mental recordkeeping as it is for public benefit, but I need to know if I'm missing anything...

Stuff I can just buy
- 6MT unit
- shifter linkage & boot
- starter & bolts
- R180 rear end
- pedal box
- halfshafts/axles (do I need the hubs too?)
- clutch
- clutch master & slave cylinders, hydraulic hose
- flywheel (lightened?)
- rear subframe bushings
- DCCD controller

Stuff I need to have made/done
- transmission mounts
- pedal box modification
- wiring harness for transmission
- pedal box modification


Stuff I don't need, but want
- lightnened crank pulley
- upgraded brakes (and possibly new wheels to fit over them)
- new springs/struts

I fixed some stuff up there... take a look. Did u ever get in touch with the guy I told you about for the parts?? $3600 is a steal for those parts

Tom

Thanks for the help with that. I'm sure if we run into problems I'll be posting here with it.

When you say that the R180 rear end needs modification, what kind of modification are we talking about?

Yeah, I did. I'm not sure if he still has them though. When I contacted him last, I wasn't sure if I was going 6MT or just 5MT, and hadn't found anyone to do the work. Now I've decided, and found someone that wants to work on it, so I will contact him again to see if he still has it. It was a JDM unit, and the JDM 5th/6th ratios probably have a higher resale value for when I swap in my Forester STi gears...

i am curious about the mods to the 180 as well... is it like just the pinion flange or worse?

well the R160 flange(pinion flange) needs to be changed over. The longer studs need to be taken from the R160 and put on the R180. There is also a notch that needs to be cut in the side so it will clearn the exhaust hanger. The strap that runs on the underbelly of the rear also needs to be cut.

Tom

None of those things sound like a superbigdeal.

Besides the fab work, is there anything crazy difficult that will possibly mess up an experienced Subie mechanic?

it's not too tough to figure out. An experienced mech should be able to figure it out

Tom

That being the case, all I need to get a hold of are the modified parts and the fabbed up crossmember... the other stuff is all pretty easy to get.

If you want to save some money, its also possible to do the 6MT conversion without using the STi half-shafts and the R180 rear diff. Just use an R160 rear diff with a 3.90 diff ratio from a late '90's Impreza.

Be sure of what 6MT you're getting. The 6MT comes in several USDM variants and several JDM variants. The JDM 6MTs (with the exception of the Forester STi 6MT) are all geared pretty low. Sixth gear has a ratio of 0.84. The USDM 6MTs have a sixth gear ratio of about 0.76 which is better for cruising. (For comparison a USDM WRX 5MT has a fifth gear ratio of about 0.74.) Also, some of the JDM 6MTs have a standard viscous center diff (like in the WRX 5MT) instead of the DCCD center diff. There are advantages and disadvantages of both types of center diffs. There are also some differences in the front diffs. Most of the 6MTs have Suretrac LSDs in the front, but a few have open front diffs (no LSD). And the most recent USDM 6MTs have a helical front diff and a revised stub axle that is not compatible with the SVX front halfshafts. If you want to see what's what, have a look here:

http://www.rallispec.com/Transmission%20chart.htm

when doing the 5/6mt swap. do you have to go hydrolic clutching? i was talking with a friend that runs a subi shop, and he recomended that jsut a cable link would take up less room and be jsut as effective. Enlighten me plz

Not really looking to cheap out here. :) I want to do it properly.

Yeah, I'm going to take you up on that offer for the Forester STi 5th/6th gears. I just need to hear back from one of my other contacts about the actual gearbox.

I was originally going to go with the JDM 6MT with viscous coupling, but they're pretty hard to come by from what I hear. Nobody seems to want them, everyone wants DCCD.

I didn't know about the helical front diff being incompatible... I'll have to pay attention to that. Could I just use the front halfshafts from the STi drivetrain in that case? I think both my potential sources have all axles included.

I have had that link bookmarked for quite some time, but thanks for posting it again for anyone else reading this. :)

While I'm replying to you, mbtoloczko, I wanted to ask you about your lowering springs. I was going to get a set, probably, and I recall there being different versions for the 5MT conversions due to lighter weight. Is that still true for the 6MT?

bump
 

So, because I had nowhere to actually store my swap parts until two days ago, I was waiting, and naturally, while I was waiting, someone bought both of the 6MT/drivetrains that I was looking into.

I might be able to get another one from both my sources, but I'll have to wait on one (he gets JDM stuff only), and the other has a second full set in stock, but it's a non-DCCD version, so that kinda sucks. I guess it'd be no worse for traction than the 5MT. It might be cheaper at any rate.

And I never did find out if I can swap front axles from another car or if I have to use the stock SVX ones (in the case of a 6MT with helical front diff); this will be kind of important. Any help on the matter would be appreciated :)

Since the Sti rear axles bolt up... I would imagine that the fronts would as well, but do hot hld me to it. Also, the dccd is not a big deal. I highly doubt there will be a day when you need to use dccd. On the topic, even if you do get a controller it will probobly b e an aftermarket one and you will never be able to use automatic mode anyway. Seriously, don't wrap your mind around the dccd portion of the trans. an BTW I have the suretrac front diff in my car and the axles worked just fine. Stop worrying about the little things

Tom

Its the later model 6MT with the helical front diff that will not mate with the SVX front halfshafts.

An installed 5MT is about 90-100 lbs lighter than the 4eat. An installed 6MT is about the same weight as the 4eat. If you're looking at my standard springs, look at the drop quote for the 4eat. :-)