[BC622B05STI]

Hey guys, I need some advice regarding what It takes to fit RA impreza Six speed Trans into a Legacy. What driveshaft would I need to Use and also what halfshafts etc I am thinking about changing uprights (Knuckles) to impreza so I can fit Bigger brakes. I would prefer to use earlier RA gearbox Pre DCCD and four bolt bellhousing if possible. I would like to know if I can Use Impreza uprights and if possible any advice on what model Impreza STI knuckles might work and what would be the best possible combination to use. I would appreciate any links to info regarding this or any advice. Also the other obvious question would be do the bigger brakes fit the uprights( knuckles) if I was to change the wheels to accomodate them but then with bigger brakes and rotors I would need to change backing plates so will any fit to the Legacy ones?

[BC622B05STI]

I would Also like to use an intake manifold setup as in the picture I will attach to this post does anyone have one of these or can you tell me if there were any production models with this setup?

[boostin]

That's a stock EJ20G manifold, but the power steer pump and alternator have been moved to be more centred.

[BO<---->XER]

I like what i see in that photo! was this setup in a road going vehicle?

[BC622B05STI]

No that was a early group A Legacy, It's basically what I hope to use on my Legacy. Boostin, do you know where I can get an EJ20G manifold ? What cars were they fitted to?

[boostin]

The stock BC/BF turbo engine is EJ20G. You may find the SS turbo has the same manifold. The pipe running under the manifold looks custom.

[BC622B05STI]

My intake from the legacy 2.2 ss is different and there is no room for the inlet to run under the manifold. Do you think NZ version BC/BF could be set up like that? What manifold would you use if you had a choice maybe later IMpreza because I have been told they flow better?

[boostin]

You would need to fit a different coolant cross pipe, fuel rail and power steer lines no matter what you do.

[rex-leggy]

id say hes running intake spacers of some kind......there's not alot of room under those intakes

[Reuben]

Yeah, the 2.2 turbo SS's in the states have SOHC heads, and just use the USDM SOHC N/A intake manifolds.

Also, by knuckles, do you mean hubs? I'm not sure on the terminology, I thought knuckles were something else.

As for fitting impreza hubs, um, anything goes, the front hubs should be the same right up till the V7, and even then i'm not sure if they changed. As for the rear hubs, well, match them to the brakes you want, if you want rear 2-pots, you will need hubs off a GC8 with rear 2-pots. If you want rear brembo's, you'll need hubs off an STi with brembos...

[BC622B05STI]

Yes Reuben I don't know why but the Subaru tech manuals call them Knuckles and also parts department here used the same term when I bought them for my 05 sti. Of course in racing and specially open wheel we call them uprights.
Anyway It sounds like I have a few options here. The guy that is making the crossmembers Is not sure if they will fit my car I told him I have confirmed they will. Just like these other parts, it is great that they all interchange

[DacerX]

There are lots of different hubs from v7 onwards so when using the 6 speed it's a rear mix and match, trust me I know I'm doing it as we speak and it's not easy with the old girls, as I said in my pm organize a Skype call and I'll explain it all out

[Reuben]

Hmmmm, yeah, there can be compatibility issues, but it always works out if you keep things specific to a certain version. I can put anything from a V3 sti onto my engine for example, or i could put in a V5 engine in, and use anything from a V5, but if i try and mix V3 and V5 parts, you get big issues with daisy chain away until you give up or start fabricating adaptor plates and BS like that..

If you go with Version 8 hubs, and brakes, and keep them with a V8 gearbox, axles, crossmembers, lateral arms and control arms etc, then everything will work fine with each other. Start mixing hubs with different version arms, with different version crossmemebers etc, you might run into issues.

[spark_38]

Did the early RA boxes come in 6spd?

I thought it was only 2000 onwards that the impreza had 6spd, and that would be a 6 bolt bellhousing, or is it 8? Either way, I don't use them all.

From what I've experienced, all Subaru gearboxes seem to be the same dimensions - the 5spd and 6spd have the same mounting points - only the rear diff and driveshaft differ in length.

[DacerX]

Reuben, on 02 November 2011 - 8:55 AM, said:

Hmmmm, yeah, there can be compatibility issues, but it always works out if you keep things specific to a certain version. I can put anything from a V3 sti onto my engine for example, or i could put in a V5 engine in, and use anything from a V5, but if i try and mix V3 and V5 parts, you get big issues with daisy chain away until you give up or start fabricating adaptor plates and BS like that..

If you go with Version 8 hubs, and brakes, and keep them with a V8 gearbox, axles, crossmembers, lateral arms and control arms etc, then everything will work fine with each other. Start mixing hubs with different version arms, with different version crossmemebers etc, you might run into issues.

You cant use V8 lateral arms in the BCs too wide on the track

[DacerX]

Yeah i have had no issues putting mine it its just he drive shalf to the diff issues, but this all depends on what car it is, and what diff u are using

[spark_38]

DacerX, on 02 November 2011 - 5:00 PM, said:

Yeah i have had no issues putting mine it its just he drive shalf to the diff issues, but this all depends on what car it is, and what diff u are using

I would assume a 6spd would use a 3.900 diff, most would be R180. I had to use a slightly shorter driveshaft in mine.

[DacerX]

yeah thats the one, i had to use a BC auto shalf and then had to have new holes drilled on the diff and then balanced

[BC622B05STI]

Thanks for the responses, you guys on here are great. Although I can do the work it is difficult to do this project without your information.....props to you all and keep the thoughts and advice comming it is very much appreciated
This forum has by far been the best I have been on and I know it's because of all the years experience you all have had with all the Japanese Subaru model Varients. Still many more questions to go. You guys provide the info.....I'll do the work....what a team!

[BC622B05STI]

DacerX, on 02 November 2011 - 5:20 PM, said:

yeah thats the one, i had to use a BC auto shalf and then had to have new holes drilled on the diff and then balanced

Aren't you allowed to shorten driveshafts over there? I know of several driveshaft places that will do that but I know regulations are tight in NZ. I think if I fit Six speed and the flange and splines were the same I would have my one shortened because It was replaced recently