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sixspeedlegacy 06-17-2011 07:16 AM

My New Project: Building a S401
Hey Everyone,

I posted this over on NASIOC where I have a bit more history but figured the legacy crowd would also enjoy this build.

My car is a 2001 with only 39k on it, however since it has essentially been a constant project from 2004 and up it has never really been complete. For example:
Since I went back to stock motor I have had a constant CEL since I have a TCU hooked up but no auto transmission for it to control. I have no cruise control and no air conditioning. I have a tape player but the other 2 DIN slots are wide open. My speaker grills are missing and I only have 2 front speakers installed. I have various interior panels missing and no spare tire or trunk floor. I could go on I'm sure...

I entertained the idea of the new Subaru coupe when it was rumored to be AWD and turbo, which unfortunately did not happen so that will not happen.
I then decided to utilize my 2001 chassis with only 39k on it and build a car I've always wanted for cheaper than I could ever buy a similar car outright. :)

I have forever held the S401 as the ultimate car and ultimate Legacy for my model year. Although I can't build an exact replica of that car I would like to build my own version utilizing a USDM STi drivetrain.

Since I am essentially buying a "new" car(but building it), I had some criteria:
1. 100% OEM reliability, working cruise control, working A/C, No CEL's, 100% factory looking swap.
2. All parts must have equal or lesser miles than my current vehicle

With those criteria in mind I began my hunt for a suitable drivetrain. After bidding on a few salvage cars and losing I realized I likely would not find a salvage STi with low enough miles and an unquestionable drivetrain in my price range. I then found a 2006 STi drivetrain with less than 29k miles and snagged it off ebay.

Originally I had planned to bid on a salvage turbo baja and just swap that drivetrain and call it a day. However, after I thought about it I knew I would not truly be content unless I had a 6mt back with all the supporting hardware. :D

I am planning to swap an entire 2004 Baja wiring harness and run a 2004 Sti ecu. For DCCD I will have to run a DCCDPro unit because having looked at the wiring diagrams this will be the easiest and cleanest way to do it. My goal is to have minimal splicing and wiring needed which is the reason to use the Baja harness since it uses the same manual HVAC and airbag setup.

The swap will start out stock to shake everything down and make sure I have no CEL's. Then I'll move to stage 2 after everything is good and stop there.
Special delivery:
2006 STi motor
My car looks on its future 6mt.:) I wanted a 2006+ for the better syncros and bit better gearing. The 2007 gearing would have been ideal but the final gear is the same and I don't care about drag racing, only in school zones. I previously had a 2004 six speed so this will work just fine.
And the fun begins...some gems from the previous owner makes me wonder if this was just for gauges. I'll definitely be doing a compression test as soon as it has its first heat cycle. Luckily the seller has granted me a 30 day warranty from the day I actually start the motor, so far the customer service has been top notch.
This was babied right? Should a clutch with 29k miles on it look like this? One of the reasons I'll be doing a compression test.

With my luck the motor will end up being blown after I finish it all but I'm trying to stay positive and definitely feel like if there is an issue I at least won't be hung out to dry by the company I bought it from so that is a positive.

Much more updates in store. In reality I likely won't be able to finish this until the end of July/August with my summer schedule but I'll be doing work as I can.


nemo 06-17-2011 07:17 AM


rao 06-17-2011 07:38 AM

Looks good.

W1CKED 06-17-2011 07:41 AM

Wow...this should be an interesting build.

Dodik 06-17-2011 07:59 AM

once the swap is done im sure you'll be able find all exterior parts for it as well. interior pieces shouldn't be that hard to replace either. i guess its good that you're after S401 and not rs30. Keep us updated on this we are way more interested to see progress than NASIOC

BrandonJ 2001 GT Limited 06-17-2011 02:23 PM

I am defiantely watching this...This is my exact dream within the next couple years. Please keep us updated throughout.

whitetiger 06-17-2011 02:29 PM

me too. I have a soft spot for the BE legacy.

joelwatts 06-17-2011 02:35 PM

subscribe. this build has my name all over it.

sixspeedlegacy 06-17-2011 03:18 PM

Thanks guys,

I have a majority of the parts already in the garage but still need a few more pieces for it to be complete.

Part of me wants to go crazy and do new paint since I'll literally have the whole car stripped down anyways but at this point I can't afford any more unnecessary expenses:lol:

I still need to snag the critical Baja Turbo hood and have it painted along with my front bumper. I do still have a CF Rev D hood I could use in a pinch but that would be kind of a band aid since I don't want to install hood pins.

I will also need to get a fuel pump up to the task. Deciding between the walbro, DW300 or Aeromotive. Will likely not get the walbro even though it would be the cheapest route.

The wiring is still a little of an unknown. I have been over the wiring diagrams and they are extremely similar, a majority of the components should just be plug and play which is what I want. The main fuse box in the engine bay may be slightly different so I am going to look at that and order it if that is the case. I essentially have otherwise ordered a full brand new 2004 Baja harness: Front harness, bulkhead harness, rear harness. I may have missed the most important one which is the fuel tank harness. The fuel pump controller is all I really am concerned about for the rear so if there is an easy and clean way to just install the FPC without all the new wiring I will go that route.

I originally had planned to just use all OEM stereo but after there wasn't really a cheap option for replacing my stock speakers I bought some Polk DB's. I also have a single Polk Momo MM100 lying around in my garage from back in the day when I used to have 4 in the trunk:lol: So I'll be making a spare tire sub enclosure to keep it stealth and so I still have my full trunk and installing a small sub amp under the passenger seat.

I just ordered some replacement door panels from a salvage yard, so my interior will be able to look nice again. I got the leather ones to go with my leather seats I put on way back in the day. If I save a bit more I may put in a full 2011 Sti seat setup but I need to take more measurements and decide if I want to mess with bracket fabrication.

Speaking of fabrication, I'm probably most excited to fabricated the new exhaust. Like I said I'll have to run the stock DP for now but I'll be making a 3" stainless steel setup with a large Magnaflow muffler and use a stock STi tip to keep it OEM looking. :) My goal is to have it fire on the first try and I can't wait to hear it. I got as big of a muffler as possible because I want it nice and mellow and deep.


BrandonJ 2001 GT Limited 06-17-2011 03:21 PM

I had to go check up on what the S401 entailed. *drool*

It sucks USDM doesnt get some of the models the JDM market does, I would have definately been interested in the S401 back in 02.

BrandonJ 2001 GT Limited 06-17-2011 03:38 PM

Could always go FMIC if you cant obtain the Baja hood or the cost is more than you want to spend. I have seen CF replacement Baja hoods from VIS. IMO I dont like the cutouts as well on the VIS though as the factory B4/turbo Baja hoods.

sixspeedlegacy 06-17-2011 04:04 PM

I am definitely going OEM Baja hood, I wish they were aluminum like the JDM B4 hoods but oh well. I am staying topmount, as I want to keep OEM components where I can.


2000_LegacyOutback 06-19-2011 09:13 PM

cant wait to see the final product!

sixspeedlegacy 06-19-2011 09:40 PM


Originally Posted by 2000_LegacyOutback (Post 3435953)
cant wait to see the final product!

Thanks! I am excited as well. :)

I am waiting on a few parts to still be delivered from the place who I bought the drivetrain from. They forgot a few parts plus I discovered the previous owner tightened the turbo inlet to the point where it tore through the rubber so he is getting me a new one from the subaru dealer. :) On a positive note though there is no shaft play on the turbo so I have that going for me haha.

I believe my only remaining parts to order before I could reasonably start the swap are:

rear wheel bearings/hubs
Baja Turbo hood/scoop/splitter
Aftermarket Fuel Pump
likely Baja instrument panel harness

I did receive some parts over the weekend. Some new front axles(needed male stubs to go into the 6mt), got them off ebay so I'm a bit skeptical as they were only $80 a piece but they look good. We'll see how they stand up to some launches and flat foot shifts in the future:icon_mrgr

The annoying thing is I will likely not be able to start the swap before I go on vacation July 8th and I won't return until the following sunday. So the earliest I can likely do anything will be July 22nd. :(

I am going to try and do some of the smaller peripheral things in the mean time though. I worked on one today for the interior. Once I get actual physical progress I'll post up pics.


2000_LegacyOutback 06-20-2011 04:10 PM

sounds great! good luck

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