[Combat Chuck]

As of right now, please correct me if im wrong, I know i will need a 2004 STI flywheel, clutch, pressure plate, slave cylinder, and rear hubs. I suppose the hubs means i need the whole rear hub/knuckle assembly. My front hubs/axles will be retained. Will my coil overs directly bolt up to the new rear hubs just fine? Is there anything I am missing?

The flywheel bolts are actually a different part number, if you can get the bolts I would, otherwise the stock bolts will work. You are correct that you need the whole rear hub/knuckle assembly. You are also correct that your coil overs will directly bolt up to the 2004 STi rear hubs just fine.

I have the rear kartboy adapters for the brakes, I suppose i will no longer need those with the sti rear hubs as well.

Correct. Best of luck with the swap!

 

[WRickX]

Hi Everyone, I'm pretty new to Subarus and car modifications of this magnitude, but I've read this whole thread and I'm taking the plunge. I found a 2005 STi with a blown motor and I'm buying the entire drivetrain to swap into my 1997 Impreza Brighton coupe. My car has a factory EJ18 and 5MT. I am trying to follow option #1, but I won't be doing an engine/ecu/wiring swap until I can save enough money to do it right.
-Does anyone know if the 6MT will bolt up to the lowly EJ18? I would like to get this running and driving with my stock engine and save for a better engine setup while I continue to educate myself.
-Do I need to take the clutch & brake pedal assembly, or will my 97 pedal assembly work?
-What clutch master cylinder should I use?
-What brake master cylinder should I use? My car was factory disc front, drum rear, NON abs.
-I need hydraulic clutch lines, right?
-I'd like to overhaul my brake lines, do I buy lines for a first gen Impreza, or an 05 STi? Do I need to fab up some kind of hybrid or use an adaptor?*
-I'm concerned about my track width. I bought a rear subframe from an 05 wrx sedan and (aftermarket) adjustable lateral links. What trailing arms should I use (GC or GD STi?) Should I use my stock front lower control arms, or the GD STi front lower control arms? Should I swap the front subframe/crossmember too?
-I'll be running the oem BBS STi 17" wheels that are 5X114.3.

1. Full STi driveline swap
STi 6 speed clutch I'm buying a new Exedy oem style clutch
STi 6 speed flywheel Should I buy a new oem flywheel? Or an Exedy lightweight? Eventual engine build plans will be 300hp or less.
STi 6 speed pressure plate I believe it comes in the clutch kit, FJK1000
STi 6 speed clutch slave cylinder Can I use the one from the donor car, or should I buy new oem? I think it was stock with 85k miles
STi 6 speed transmission Got it, anything I should do to it before it goes in?
STi 6 speed transmission mount Should I buy stock, or group N? This is most likely going to be a street car only
STi 6 speed shift linkage I have the complete linkage with Kartboy short shifter. I will replace bushings and the joint.
STi 6 speed drive shaft Got it, looks to be in good shape. Should I replace any hardware or u-joint as preventative maintenance?
STi front axles Have them, they look good.
STi front hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi R180 rear differential (final drive matching that of the transmission) Have it. Would like to paint it with POR 15 and replace the seals with new oem.
STi R180 rear axles Have them, they look good.
STi R180 rear hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi front and rear Brembos Have them, I would like to do a rebuild but I'll probably try them as they are first.
STi Brembo rotors front and rear Have them, and I'll probably try to use them for a while before replacing due to cost.

(If using '05-'07 hubs, custom coil overs are recommended to maintain proper suspension geometry to mate from the 5x114.3 bolt pattern to the GC top hat bolt patterns. These custom coil overs would be GC top hats with a '05-'07 STi bottom sleeve to mount to the hub) *I have the stock 05 STi struts, with some kind of tein lowering springs. I'm going to try to swap the rear tophats for early turbo legacy pieces (if available) to make it work till I dial everything in.

Any other things I should know?

 

[FryphaX]

-Does anyone know if the 6MT will bolt up to the lowly EJ18? I would like to get this running and driving with my stock engine and save for a better engine setup while I continue to educate myself. -

Yes, you can swap the drive train first. You will need the matching differential to the trans and an automatic driveshaft (I believe). Your best bet is to swap the trans and entire rear subframe/suspension together. Just pull the entire STI unit and put it in your car. Same thing for the front suspension/subframe.


-Do I need to take the clutch & brake pedal assembly, or will my 97 pedal assembly work?

Yes and yes. Being a 97, that's a cable clutch eh? There's a thread here on how to do a cable to manual swap, there might be cutting required.

-What clutch master cylinder should I use? STI
-What brake master cylinder should I use? STI
-I need hydraulic clutch lines, right? STI...errr get them from the swap.
-I'd like to overhaul my brake lines, do I buy lines for a first gen Impreza, or an 05 STi? Buy for your car.

Get the entire car.

1. Full STi driveline swap
STi 6 speed clutch I'm buying a new Exedy oem style clutch
STi 6 speed flywheel Should I buy a new oem flywheel? Or an Exedy lightweight? Eventual engine build plans will be 300hp or less.
STi 6 speed pressure plate I believe it comes in the clutch kit, FJK1000
STi 6 speed clutch slave cylinder Can I use the one from the donor car, or should I buy new oem? I think it was stock with 85k miles
STi 6 speed transmission Got it, anything I should do to it before it goes in?
STi 6 speed transmission mount Should I buy stock, or group N? This is most likely going to be a street car only
STi 6 speed shift linkage I have the complete linkage with Kartboy short shifter. I will replace bushings and the joint.
STi 6 speed drive shaft Got it, looks to be in good shape. Should I replace any hardware or u-joint as preventative maintenance?
STi front axles Have them, they look good.
STi front hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi R180 rear differential (final drive matching that of the transmission) Have it. Would like to paint it with POR 15 and replace the seals with new oem.
STi R180 rear axles Have them, they look good.
STi R180 rear hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi front and rear Brembos Have them, I would like to do a rebuild but I'll probably try them as they are first.
STi Brembo rotors front and rear Have them, and I'll probably try to use them for a while before replacing due to cost.

(If using '05-'07 hubs, custom coil overs are recommended to maintain proper suspension geometry to mate from the 5x114.3 bolt pattern to the GC top hat bolt patterns. These custom coil overs would be GC top hats with a '05-'07 STi bottom sleeve to mount to the hub) *I have the stock 05 STi struts, with some kind of tein lowering springs. I'm going to try to swap the rear tophats for early turbo legacy pieces (if available) to make it work till I dial everything in.

Any other things I should know?

You actually put thought into this. Well done. Answers in bold in your quote and here's my opinion/questions:

So you have the entire car at your disposal? Get the entire thing. At the very least get the entire drivetrain/suspension/subframe kit. It's maybe 20 bolts and the entire thing is out of the car. Then bolt all that into your car. You'll need electronics and wiring from inside the car as well to fully utilize the transmission.

You should start a build journal. I started a total swap with the picture below and it's the way to go. It's the way to go. Sell the 05 WRX stuff and just take everything from the STi. How attached to the stock interior are you? Have you considered a dash swap?

 

[WRickX]

You actually put thought into this. Well done. Answers in bold in your quote and here's my opinion/questions:

So you have the entire car at your disposal? Get the entire thing. At the very least get the entire drivetrain/suspension/subframe kit. It's maybe 20 bolts and the entire thing is out of the car. Then bolt all that into your car. You'll need electronics and wiring from inside the car as well to fully utilize the transmission.

You should start a build journal. I started a total swap with the picture below and it's the way to go. It's the way to go. Sell the 05 WRX stuff and just take everything from the STi. How attached to the stock interior are you? Have you considered a dash swap?

Thanks. This thread, and information gathered on the gc8 facebook page, have been very helpful. In my area, there are a few shops that actually specialize in just buying wrecked STis and parting them out for max profit locally and on eBay. So the price to get a wrecked/non-running complete vehicle on Copart, craigslist, facebook, etc. is high due to competition, and I just didn't have the budget to buy a fully functional 04-07 as a donor. I'm buying parts from an individual who was parting out the car. I don't have the ENTIRE car at my disposal. The owner still needs to end up with some kind of rolling shell left. He's willing to take most of the stuff I need for the swap off to sell me, as he has a spare wrx with most of the drivetrain left. The STi interior is mostly gone. The rack & pinion is not available, and neither is the front subframe. I do have the stock STi sway bars too. I can have the rear sti lateral links, but I figured adjustability would be more beneficial with my gm6 chassis, so I was going to sell the stock STi rear arms.

I'll start a journal, I need to get an imgur or whatever since photobucket used to be my go-to. I'm not attached to the stock interior, but I don't want to pull the dash apart until it's time to do the motor.

For pure functionality sake, should I buy a replacement STi fuel tank to replace my stock piece? I don't believe I have rust issues with my current setup, so assume that's not an issue.

 

[Michaeld]

Hi Everyone, I'm pretty new to Subarus and car modifications of this magnitude, but I've read this whole thread and I'm taking the plunge. I found a 2005 STi with a blown motor and I'm buying the entire drivetrain to swap into my 1997 Impreza Brighton coupe. My car has a factory EJ18 and 5MT. I am trying to follow option #1, but I won't be doing an engine/ecu/wiring swap until I can save enough money to do it right.
-Does anyone know if the 6MT will bolt up to the lowly EJ18? I would like to get this running and driving with my stock engine and save for a better engine setup while I continue to educate myself.
-Do I need to take the clutch & brake pedal assembly, or will my 97 pedal assembly work?
-What clutch master cylinder should I use?
-What brake master cylinder should I use? My car was factory disc front, drum rear, NON abs.
-I need hydraulic clutch lines, right?
-I'd like to overhaul my brake lines, do I buy lines for a first gen Impreza, or an 05 STi? Do I need to fab up some kind of hybrid or use an adaptor?*
-I'm concerned about my track width. I bought a rear subframe from an 05 wrx sedan and (aftermarket) adjustable lateral links. What trailing arms should I use (GC or GD STi?) Should I use my stock front lower control arms, or the GD STi front lower control arms? Should I swap the front subframe/crossmember too?
-I'll be running the oem BBS STi 17" wheels that are 5X114.3.

1. Full STi driveline swap
STi 6 speed clutch I'm buying a new Exedy oem style clutch
STi 6 speed flywheel Should I buy a new oem flywheel? Or an Exedy lightweight? Eventual engine build plans will be 300hp or less.
STi 6 speed pressure plate I believe it comes in the clutch kit, FJK1000
STi 6 speed clutch slave cylinder Can I use the one from the donor car, or should I buy new oem? I think it was stock with 85k miles
STi 6 speed transmission Got it, anything I should do to it before it goes in?
STi 6 speed transmission mount Should I buy stock, or group N? This is most likely going to be a street car only
STi 6 speed shift linkage I have the complete linkage with Kartboy short shifter. I will replace bushings and the joint.
STi 6 speed drive shaft Got it, looks to be in good shape. Should I replace any hardware or u-joint as preventative maintenance?
STi front axles Have them, they look good.
STi front hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi R180 rear differential (final drive matching that of the transmission) Have it. Would like to paint it with POR 15 and replace the seals with new oem.
STi R180 rear axles Have them, they look good.
STi R180 rear hubs Have the whole assembly off the donor car, not sure if I should replace anything?
STi front and rear Brembos Have them, I would like to do a rebuild but I'll probably try them as they are first.
STi Brembo rotors front and rear Have them, and I'll probably try to use them for a while before replacing due to cost.

(If using '05-'07 hubs, custom coil overs are recommended to maintain proper suspension geometry to mate from the 5x114.3 bolt pattern to the GC top hat bolt patterns. These custom coil overs would be GC top hats with a '05-'07 STi bottom sleeve to mount to the hub) *I have the stock 05 STi struts, with some kind of tein lowering springs. I'm going to try to swap the rear tophats for early turbo legacy pieces (if available) to make it work till I dial everything in.

Any other things I should know?

Lots of great questions, here’s ones i can help with based of my swap experience:

- Your stock manual pedal assembly will work, assuming it’s already manual. Clutch master cylinder will work as well if you have a hydro clutch. If not, GC stuff will work fine. I never upgraded anything to GD and never had an issue. GD Pedals will require massaging to make fit, IMO not worth the trouble as bolt in GC Stuff.

- Brake master cylinder is going to be a little harder. SVX non ABS master cylinder is the perfect match. 1 1/16 size, no need to delete ABS. But they’re discontinued. Might be able to snag one off Rockauto like i did, or ask around on the for sale pages. There’s write ups out there on how to delete ABS on STi master cylinders if need be, but you need the larger 1 1/16 bore for the brakes to be effective.

- I used STI stainless braided lines, no issues.

- rear subframe, you’ll use GD STi lateral links to allow the axles to fit properly, they’re a little wider. It won’t account for much width, so don’t worry about it. I’d swap front subframes only to accommodate a turbo engine, otherwise no need. Can keep stock GC lower control arms with the 6MT and be fine.

- as for maintenance items on the stuff you got, i never had issues with using used stuff, but wear items are good to replace while it’s apart and save you the headache later. I’d replace hub bearings at a minimum. I never touched my driveshaft hardware. Trans mount is up to you, I’d honestly go with whatever is cheaper. If price is marginal, snag the group N and be happy. Won’t make much difference behind the EJ18, but if you ever upgrade you’ll be glad you had it in there.

Like mentioned above, good job doing your homework and asking the good questions. The swap isn’t difficult, just get everything you need sorted out first and you’re golden.


Sent from my iPhone using Tapatalk

 

[Combat Chuck]

As said by everyone else, well researched! A few things I'd note:
You will need a new pedal box, your cable clutch pedal box is different from the 98-01 Impreza 2.5 RS hydraulic pedal box.

I wouldn't worry about the master cylinder right away. Having the smaller non-ABS master cylinder will give a bit more pedal travel, but the Brembo brakes will still function and have bite. If you want a firmer pedal later, look into the master cylinder upgrade specified above.

However, I would make sure that you find a non-ABS rear disc brake proportioning valve. This will prevent your rear brakes from locking up before the fronts and give you a correct brake bias. Another option would be to replace your stock proportioning valve with a manually adjustable one.

As for control arms and lateral links: If you plan to go turbo eventually, swap the front subframe as well. You will not be able to run the GD STi control arms without this. As for which track width to use, it's up to you. The wider track width requires rear GD lateral links, a front GD subframe, and front GD control arms. If you're going to run STi sway bars, I'd recommend this route. Otherwise, you can run the front GD subframe, front GC control arms with shims, rear GC lateral links, and GC aftermarket sway bars.

Axle wise, I am running GD STi axles with the GC track width in the rear, and the axles are compressed a bit, but do function properly. It may generate a bit of rear end noise, but it's hard to tell, as I have Whiteline diff bushings and the subframe lockdown kit installed as well. GD track front and rear will free them up, but I would not run a GD track in one end with a GC track in the other.

Regarding subframes, they do not appreciably alter your track width, that is done by the lateral links in the rear and the control arms in front. Choose them based on condition in the rear (rusty vs. newer, etc) and your choice of control arm and motor (turbo yes or no) in the front.

The fuel tank is up to preference, although from what I understand the STi tank has better baffling and the pump arm is better suited for high speed cornering. While I've not performed the swap on any of my cars, if I had the opportunity to do so I would.

 

[jdmdominik]

I have a question that maybe somebody has an answer to, i just find it weird. So i did a complete drive train swap, you know the hole shabang. My weird situation is that before the swap it seems that it was a lot more room between the rear tire and the back bumper. after the swap it seem that i have almost no space and i'm limited the amount i can lower the car because of the tire rear bumper to tire clearance. any one wants to chime in?

 

[Combat Chuck]

Did you use GD lateral links and axles?

 

[jdmdominik]

Did you use GD lateral links and axles?

I used everything out of a 2005 JDM STI Forester. Tranny, diff, subframes, lateral links, Brembos and so on.

 

[Combat Chuck]

SG Foresters have the same track width as the GD, which is wider than the GC. That's why your wheels are out further.

 

[mike-tracy]

I reused the GC crossmember, mustache bar and trailing arms in my 6mt swap. Everything else was 04 STI (hubs, diff, axles) or GG WRX wagon (06 Saabaru Aero to be precise), such as lateral links. Wheels are as centered as with the stock equipment.

When I did a lot of suspension changes to my 98 OBS (suspension, rear disc swap, sways, etc), the wheels visually pulled forward like I think you're talking about. This typically happens when you lift an OBS. The solution in that case is Gen 1 outback trailing arms, they are slightly longer and make the wheels almost centered again.

 

[Combat Chuck]

Ah, I think I misunderstood the question. Is this about the wheels appearing centered from the side profile, or poking out too far from the rear profile? If it's about the wheels not appearing centered from the side profile, it's likely the use of the SG Forester STI trailing arms.

 

[stg2lgcy00]

Ah, I think I misunderstood the question. Is this about the wheels appearing centered from the side profile, or poking out too far from the rear profile? If it's about the wheels not appearing centered from the side profile, it's likely the use of the SG Forester STI trailing arms.

^You got to it before me, that was the only thing I could think of that would push the wheels further back.

Haven't posted in a while but this thread was a huge help. I'm still running the same setup I put in 5 years ago without any problems. 05 usdm 6spd, wrx wagon driveshaft, 3.9 r160, rs front axles, wrx wagon rear axles and rs hubs/spindles on all corners.

No plans to really change anything in the drivetrain but will be switching from H6 rear brakes to 05 LGT rears soon.

 

[jdmdominik]

I reused the GC crossmember, mustache bar and trailing arms in my 6mt swap. Everything else was 04 STI (hubs, diff, axles) or GG WRX wagon (06 Saabaru Aero to be precise), such as lateral links. Wheels are as centered as with the stock equipment.

When I did a lot of suspension changes to my 98 OBS (suspension, rear disc swap, sways, etc), the wheels visually pulled forward like I think you're talking about. This typically happens when you lift an OBS. The solution in that case is Gen 1 outback trailing arms, they are slightly longer and make the wheels almost centered again.

I reused the GC crossmember, mustache bar and trailing arms in my 6mt swap. Everything else was 04 STI (hubs, diff, axles) or GG WRX wagon (06 Saabaru Aero to be precise), such as lateral links. Wheels are as centered as with the stock equipment.

When I did a lot of suspension changes to my 98 OBS (suspension, rear disc swap, sways, etc), the wheels visually pulled forward like I think you're talking about. This typically happens when you lift an OBS. The solution in that case is Gen 1 outback trailing arms, they are slightly longer and make the wheels almost centered again.

well the JDM JDM Forester is pretty much is pretty much an 04 STI. And yes the problem I have which is not really a drivability problem is more of a aesthetic problem is that the rear wheels looks like they are push to the rear a bit. So to fix the problem I need shorter trailing arms?

 

[jdmdominik]

You can see in this picture. Is not much but is not 100% centered.

 

[stg2lgcy00]

Wow, thats pretty dramatic. Yea I would say try to get a measurement on the length of GD rear trailing arms to compare first before doing anything.

 

[Combat Chuck]

well the JDM JDM Forester is pretty much is pretty much an 04 STI. And yes the problem I have which is not really a drivability problem is more of a aesthetic problem is that the rear wheels looks like they are push to the rear a bit. So to fix the problem I need shorter trailing arms?

That's not really true. While the base engine is the same as the 04 STi and the trans is similar although with different ratios and not DCCD, the suspension is 100% Forester. This means the front subframe would include the spacers, the strut/spring setup is taller, and to compensate in the rear, the trailing arms are longer for the taller ride height. Put either GC or GD trailing arms on and that will solve your issue.

 

[jdmdominik]

Wow, thats pretty dramatic. Yea I would say try to get a measurement on the length of GD rear trailing arms to compare first before doing anything.

Thank you for the advice. Will measure up then arms and then look around for shorter ones to bring the wheel forward. On the other hand, by adding shorter arms and bring the wheel center the Toe will be super negative. I guess I will have to get rid of the STI lateral links and get adjustable.

 

[Combat Chuck]

Is your car's toe actually neutral right now? I'd expect it to be off currently, and be corrected by the trailing arm from the proper chassis.

 

[jdmdominik]

Is your car's toe actually neutral right now? I'd expect it to be off currently, and be corrected by the trailing arm from the proper chassis.

I got an alignment a while back and is neutral at the moment. It if I replace the trailing arms I don’t know if there will be enough adjustments to compensate for the the toe.