STi 6spd swap and diffs

Finally I did manage to get an almost new (16k miles) STi 6spd, so decided to make the swap, as my stock 5spd is getting worse at around 330 hp.

The parts going to be changed:

- stock front diff

- stock rear diff

- stock 5spd

- stock shaft

- stock front and rear axles

At first I was thinking of just replacing the rear diff with an STi R180, leaving the front open, as is - I do not want DCCD. We also gonna replace the GT push type clutch with an STi pull type.

Actually I would like to built an STi drivetrain - or better. The question is what type of diffs do you guys recommend?

I was thinking of getting torsen diffs to the front and rear as well. I am just curious how the machine would handle... Are there any pros/cons?

Or just have the R180 at the rear and go with something else at the front? I heard that the 07 STis are using torsen at the front and the rear as well. Is this correct?

Any ideas?

PS: got a decent GT 5spd manual for sale with 22k miles

Well, if you got sti 6spd you got front diff (should be lsd) as well as center diff already

All you need is proper shaft and R160 3.90 ratio rear diff. If you want STI's R180 diff, you need to change rear axles, hubs and brakes.

You do not need to change front axles.

Well, if you got sti 6spd you got front diff (should be lsd) as well as center diff already

 

All you need is proper shaft and R160 3.90 ratio rear diff. If you want STI's R180 diff, you need to change rear axles, hubs and brakes.

 

You do not need to change front axles.

Got no front or rear diff in the set...no DCCD as well Parts are from an 05 STi

Definately EDM. I could not source a JDM one, and I need the long 5th and 6th gear found in the European version, as sometimes I take long journeys on highways.

So, any ideas/tips which ones to get?

I am pretty sure it is an 1.1:1 in the EDM STI too.

3.900 at the rear (3.545 x transfer 1.1)?

Good luck.

 

Good luck.

Thx, I'll need that

did you talk to Andrewtech? they can get you something better than just another OEM STI tranny. They have PPG gearsets and more.. you should give Andrew a call. 240-683-1000

Hey Xenonk, thx for the idea, I'll give it a shot - however I think shipping to Europe would be a fortune. Nevermind, I'll try! Thx!

If you dont want the DCCD, just get the 07+ spec B tranny

It looks like I have the chance getting an STi Spec C...we'll see

At least I had figured out, that I can not fit a DCCD controlled EDM tranny into my USDM LGT, because the ABS sensors are different. Sooo, I have to source some EDM sensors for the EDM DCCD equipped tranny to work

yes you can. Go after market for you DCCD control.

Link, http://dccdpro.com/?page_id=5

Only 5 wires to hook up;

Support

” Spiider’s” Auto DCCD controller info.

Thank you for your purchase.

Technical Details:

• <LI class=MsoNormal>Microchip’s PIC 16f877a microprocessor running at 4mhz <LI class=MsoNormal>2 axis high resolution g-sensor <LI class=MsoNormal>custom firmware with driver adaptive capability <LI class=MsoNormal>several internal modes based on driver throttle behavior and g- sensor behavior that switch on the fly automatically
  
• DCCD calculations are using advanced formula’s instead of unintelligent “static mapping” or “lookup tables”

Installation:

Installation is recommended to be performed by a licensed auto mechanic.

“Red” = 12v positive (switched power)

“Green“ = 0v negative (ground)

“Black” = DCCD “B128 pin 1” (See attached Subaru DCCD Schematic)

“White“ = DCCD “B128 pin 4” (See attached Subaru DCCD Schematic)

“Blue“ = TPS: Non-DBW “B135 pin B7” (See attached Subaru ECM Schematic)

DBW “B136 pin B18” (See attached Subaru ECM Schematic)

These 5 wires are all you need to hook up for automatic operation. You may add an accessory switch to the 0v wire if desired to be able to turn off the system for “open” operation of your differential. It is also recommended to have at least a 10 amp fused circuit powering the DCCD.

Mike

Meantime I gave up searching on diffs for the tranny I wanted to buy - being just too complicated... Yesterday I bought a 2006 EDM STi tranny with its front, center and rear diff without driveshaft and axles.

I have decided to go "Mike-way", with an aftermarket DCCD controller. Thx again Mike

I do not want to go with aftermarket aluminium or CF driveshaft, soooo need to source a factory STi one. Anybody knows any online store that willing to ship to Europe? I had been looking at 1stsubaruparts.com, but they do not ship overseas

Any help appreciated

will the stock STI driveshaft be too short?

I think a SPec B or 5EAT driveshaft might work tho.... not entirely sure

Mike

Shoulda bought a Spec B... :lol:

Just joking. If you are looking for an easier swap, just source everything from an '07 Spec B, they come with the 6-Spd Trans, sans DCCD and with Torsen Rear Diff (can't remember the exact ratio). It will be a hell of a lot easier for you since everything is already made for the LGT. Just my .02c

Meantime I gave up searching on diffs for the tranny I wanted to buy - being just too complicated... Yesterday I bought a 2006 EDM STi tranny with its front, center and rear diff without driveshaft and axles.

 

I have decided to go "Mike-way", with an aftermarket DCCD controller. Thx again Mike

 

I do not want to go with aftermarket aluminium or CF driveshaft, soooo need to source a factory STi one. Anybody knows any online store that willing to ship to Europe? I had been looking at 1stsubaruparts.com, but they do not ship overseas

 

Any help appreciated

I am not sure, but I think I read somewhere 06-07 USDM STI transmission has different ratio. I.e. final is still 3.9, but there is 1.1 reduction in the transmission itself. Not sure if it applies to 06+ EDM STI. But then you have rear diff so you should be ok, except... now you have the problem with rear shafts. STI rear shafts won't work with LGT hubs/brakes. Big $$$$$$.

So that means unless you can get custom ones built, you need entire STI rear end (hubs/brakes). Which for USDM 05+ was 5x114.... which you don't want unless you want to swap front, too (not sure if possible). Hopefully 04 USDM STI work (5x100), but I don't know.

The lego like mix and matching sometimes is not so easy

from an '07 Spec B, they come with the 6-Spd Trans, sans DCCD and Torsen Rear Diff

The '07b does have the Torsen Rear Diff.

It doesn't have DCCD.

The '07b does have the Torsen Rear Diff.

It doesn't have DCCD.

Since I own one

The '07b does have the Torsen Rear Diff.

It doesn't have DCCD.

It also doesn't have front LSD.

I am not sure, but I think I read somewhere 06-07 USDM STI transmission has different ratio. I.e. final is still 3.9, but there is 1.1 reduction in the transmission itself. Not sure if it applies to 06+ EDM STI. But then you have rear diff so you should be ok, except... now you have the problem with rear shafts. STI rear shafts won't work with LGT hubs/brakes. Big $$$$$$.

 

So that means unless you can get custom ones built, you need entire STI rear end (hubs/brakes). Which for USDM 05+ was 5x114.... which you don't want unless you want to swap front, too (not sure if possible). Hopefully 04 USDM STI work (5x100), but I don't know.

 

The lego like mix and matching sometimes is not so easy

Yeah, I need the whole STi rear - that's for sure. The only question is - that's what Mike wrote - does the stock STi driveshaft fit the LGT or not? LGT is a bit different in size

Actually the EDM 06 STi has "longer" gears in 5th and 6th. The 1.1 reduction at the tranny is the same - only the gearing differs. But that's what I need on highways - loooong 5th and 6th.

The parts I surely need:

- STi driveshaft

- STi rear driveshaft axles

- 04 STi hubs (I have 3 sets of 5x100 rims, so I do not want to go 5x114)

Already made the STi brake swap

The strange thing I noticed on http://www.1stsubaruparts.com is that the STi driveshaft costs only $500. I mean here in europe they sell it for around $2200...what the hell? BUT, they do no ship overseas. Bump.

Any other online store willing to ship to Europe?

Yeah, I need the whole STi rear - that's for sure. The only question is - that's what Mike wrote - does the stock STi driveshaft fit the LGT or not? LGT is a bit different in size

The STi drive shaft is more then 5" to short over all. If you have or can get a STi drive shaft. And the U-joint are good. Then take it to a drive shaft co. And have the remake the shaft with longer tubes. Here in the US. A 07 Sec.B drive shaft is over $650.00. Here's a idea, Have someone you trust, buy it here & ship it to you there. Has to be cheeper then $2200.00.

The small shaft is the OEM, non-rebuildable. The other is my new shaft. It was a little cheeper then OEM, but it 3x as stong & can be 100% rebuildable for pennys on the dollar. See center pic. for contact info.

http://i99.photobucket.com/albums/l293/HAMMERDOWNGT/Subaru/0915070017.jpg http://i99.photobucket.com/albums/l293/HAMMERDOWNGT/Subaru/0915070033a.jpg http://i99.photobucket.com/albums/l293/HAMMERDOWNGT/Subaru/0915070022.jpg

If you get your R160 rear end regeared to match the STi 6MT. With the STi rear pinion flang. You can use your own half shafts.

Mike

Just and update:

STi rear axles arrived, along with the 2004 STi hubs. Still searching for somebody to ship the SpecB propshaft to Europe. No luck...

The next problem is, that we do not see any chance of getting the STi hubs on the GT. Have to figure out something...anybody any idea?