H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

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subarukenny_d
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H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

This write up will outline the major tasks required to successfully complete this swap into your Baja and get everything functioning as expected once again. It includes the mechanical, electrical, and tuning aspects of the swap. Crack a cold one and get ready cause this is a lot of information to digest.

I’d like to personally thank Travis and Jake for their efforts to complete this swap and pave the way for me to do it on my Baja, and their advice into the information below. This swap is very time consuming but can be completed in a reasonable amount of time if you have help. Start to finish, I was able to complete the entire swap in 1 month working on it as I had time after work, weekends, etc. This was also me working alone for most of the time – so if you have friends that can lend a hand it will drastically reduce this timeline.

Here is a link to Jake’s great video and build series on his Baja, give him a follow – he makes fantastic content for the Baja community!

Adventure GT on Youtube: https://www.youtube.com/@AdventureGT
Part 1: https://www.youtube.com/watch?v=LIKEFzMy-yA
Part 2: https://www.youtube.com/watch?v=z2FGMveFQgM

To get started, we need to define the scope of what we set forth to accomplish. This swap pertains specifically to swapping a 6 cylinder 3.0L engine, complete driveline, almost all wiring, and misc. components from a 2001-2004 Outback H6 (Wagon or Sedan) into your 03-06 Baja while retaining functionality of critical features and gaining that additional torque output of the H6 engine without the headache (& heat soak) of the turbo EJ255 option.

Selecting a Donor Car:

A couple notes about this swap: It is easier (less wiring to deal with) to find a NON-VDC Outback complete donor car. Acquiring a donor car is key because of how many small items you will be running back to it as you progress with your swap. Not only that but you can part out the remaining parts you will not need to help fund the project. This is exactly what I did and after all expenses going into the parts and fluids I made money on this swap. If you have the time, space, and patience for this, it's 100% worth the effort.
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Another thing to note is regarding a fuel pump controller. Some may ask “what is a fuel pump controller?” – Well, they are commonly used on the turbo Subaru platforms to control the duty cycle to the fuel pump for increasing loads, this signal is commanded by the ecu. The 01-02 H6 Outbacks DO NOT have the fuel pump controller but the 03-04 H6 Outback does…my donor car was a Base 2004 Outback H6, so it had it. The catch here is that it’s a little bit more wiring to incorporate the fuel pump controller however since the harness revision in early 2003, A LOT of other connectors on the H6 harness will be plug and play in the chassis i.e rear door/window controls, wiper motor, under the dash, engine bay, etc.

Whereas the 01-02 H6 Outback doesn’t have the fuel pump controller and just sends 100% commanded power to the fuel pump when the ignition is on. This is how it's done across the board for most Subaru’s before the 2003 wiring update.

A good rule of thumb when selecting a complete donor car or buying a harness is to try and stick with the timeframe you have. I.E if you have a 2003-2006 Baja (Turbo or N/A) Try to find a 03-04 Outback H6 donor because a lot of the connections and plugs will be plug and play not requiring repining or splicing – thus saving time.

If you are reading this and want to swap your 01-02 Legacy/Outback, try to find a 01-02 Outback H6, for the same reasons as listed above. Same applies with the Wagon/Sedan, try to find a similar time frame and style chassis and it will make your life much, much easier.

A more detailed explanation will be included in the “electrical” section of the write-up, below. Unfortunately, I will have to break this post into multiple pieces because I can not upload more than 3 photos at a time...
2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Mechanical Aspect of the Swap:

This is the not-so-dreaded part of the swap. It’s usually the wiring that scares people away from taking on this project. I started by completely ripping the stock Baja EJ25 and auto trans out of my chassis prior to moving anything over. My transmission that originally finally died after 209k miles of use. This applies for the donor car as well. I pulled the complete engine, wiring and virtually everything I would need out prior to starting the swap. Once I had a majority of the H6 stuff in my basement, 6 cylinder engine on the engine stand, and Baja ripped apart when I started bringing things over.

I found it is easier to remove the front bumper cover, driver side fender and other pieces out of my way to access the large items as well as the wiring we will need to remove/reinstall later.

Everything physically forward of the B-Pillar is almost identical to the H6 donor car, so the H6 auto trans (which is different from the 4-cyl 4EAT internally), H6 engine will fit in the engine bay nicely, and all bolts up to factory locations in the engine bay. There is other information elsewhere about how the transmissions are different, I will not be getting into that here. Most of the H6 and Turbo 4EAT share upgraded components internally.


Engine:

This is a great time to service the following components: reseal valve covers, reseal oil pan, spark plugs, replace coil packs, rear main seal, oil cooler o-ring, power steering pump and associated lines/o-rings (in my case it was leaking externally pretty bad), serpentine belt, idler pulleys, tensioner, etc. I highly recommend doing this with the motor out before you reinstall into the Baja because the front & side clearance between engine, radiator fans, and frame rails is going to really close up with this larger EZ30D motor in the engine bay…Plus most of these donor vehicles have 150k+ miles on them so you will be encountering this during your swap. This is also the time to replace the timing chain/tensioners and guides if your donor engine is noisy. A good way to determine if the chain, tensioner, and guides need to be replaced is when you hear a distinct slapping noise on cold start. Front timing cover bolts are notorious for snapping off, and might as well do a water pump if your in there servicing it.

If in the event you purchase a swap kit or a donor car without the motor or a blown engine, these EZ30D Phase 1 motors with the metal intake manifolds can be found at JDM engine importers pretty frequently, I’ve have good success with some of these engines in the past (mostly EJ20x/y). It's just best to pick it up in person so you can visually inspect what you're buying and avoid shipping costs. A couple key things to look at are the motor overall for broken components - they are tossed in a shipping container and shipped over here so they smash around quite a bit. Look for any leaking valve covers or anything we mentioned above. CHECK COMPRESSION, take your own compression tester and starter if needed, don't trust the videos they provide. I like to vet my motor myself when I am down there as they usually have a pretty nice selection to choose from. Another thing to look for is leaky exhaust valve seals. If you see a thin film oil in the exhaust ports or they look wet in the exhaust ports with the header removed, select a different donor motor. It should have a chalky, flat back appearance there.
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Transmission Options:

Keeping the 4EAT


I was able to find a low miles H6 specific 4EAT for my swap from a friend who manual swapped, the internals are different and stronger than the N/A 4EAT. If you have a baja turbo with the sportshift this may hold up, but unsure if the sport shift will function anymore unless you swapped TCU’s, which may affect the shift points and how the transmission reacts – its best to just stick with the equipment came with the H6 to avoid headache and CEL’s – this is the route I took because my baja is my wife and I’s camping vehicle which we take overlanding, etc. She is also more comfortable driving automatic, god forbid anything were to happen to me during one of our excursions and she needed to drive out. Additionally there is more wiring to attach the cruise control and get that working again. These are some of the reasons why I went the route I did.

A good idea is to replace the ATF filter and all trans cooler hoses during this time because the H6 has a remote mounted ATF filter housing attached on the inner fender near the battery during this swap. You will have the fender off already to route wiring through so this is a great time to service the filter and check for leaks.
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Ditching the 4EAT

If your donor car was purchased with blown auto transmission like mine, or you just hate auto transmissions with a passion then this may be the best route for you. Weight savings are pretty substantial if you go with the 5 speed manual over the auto, completely up to you. Travis used the stock 4.44 FD 2003 Baja manual 5 speed and rear diff was used in his swap that was actually factory equipped in his. He also used a stock EJ25 resurfaced flywheel, new clutch kit, etc. This all bolts up to the EZ30D without issue – there are other write ups that cover this so I will not be going in depth with this part. However I will be including information regarding the wiring aspect of this route below so you choose to go with it.

Rear Differential:

Use whatever matching rear diff and CV axles to your transmission selection, I kept the H6 4EAT so I swapped out the rear diff and CV’s with the H6 Outback rear diff since it was a different ratio. The H6 Outback 4EAT uses a 4.11 FD whereas the Baja is 4.44 across the board – so this is something to consider. Also I found that my N/A 05 Baja had different spline count CV axles, so this is also something youll need to swap over during this process if changing the diff out. Additionally, the U-joints and my Baja drive shaft were shot, so I brought over from the donor car as well. This physically bolted up in place of the original. Keep in mind they are different lengths between the auto and manual (manual DS being longer).
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2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Front Crossmember:

I left the original Baja steering rack, crossmember, sway bar, tie rods, etc. all in place. And the H6 engine will drop right in with no issues. Only thing you’ll need to do here is swap out the power steering feed and return lines as they are not compatible between the H4 you just ditched and H6 you are installing back in. Steering wheel, steering column, steering u-joint can also all remain original Baja equipment. The newly attached lines will hook up to your H6 power steering pump on the engine. It is a good time to replace the O-rings on the power steering suction fitting on the pump. When these are dry it will allow air into the system and the pump will cavitate.
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2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Exhaust Setup:

You will need to completely remove the stock Baja exhaust system, and retain the stock H6 front exhaust section with catalytic converters that terminates around the tail shaft of the transmission. There are also aftermarket header options if you want to go this route but will throw cel’s later on and may cause tune related issues so be ready for that. Now, this can be tuned out (ref tuning aspect of this write up) but may cause more headache than what its worth. The stock header/cat sections bolt right up and hookup to the hanger on the transmission just like it did on the H6 Outback, so this is what I did.

For the “catback” section of the exhaust system (ie from the header/cat collector back) you’ve got some options here:


1. You can keep your stock baja mid-pipe & muffler but will have to modify this to adjust the length and hookup to the H6 front section. This may warrant a loss in power as the pipe diameter is smaller and the muffler more restrictive so keep this in mind.


2. Use as much of the H6 Outback exhaust system that you can – this is the route I took and just cut off the muffler for the time being. I plan to add a custom axle-back magnaflow muffler at some point, but it is not really a priority for me at the moment.
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3. Build a complete custom mid pipe and axleback. You can have a muffler shop do this or break out the tig welder and go to town, sky's the limit here. Just keep in mind the H6 is inherently raspy so you’ll want a proper resonator and muffler to keep it at bay. Regardless, the H6 sounds fantastic with a muffler delete. It’s really up to the owner’s taste completing this swap to determine what he/she likes. 2.5” Piping for this portion is likely more than sufficient size for what we are trying to accomplish here.
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Fuel Pump Upgrade:

After doing some research I found that the stock 05 Baja 2.5 fuel pump is rated at 65lph (12v @43.5psi), the stock 04 H6 Outback received a slightly larger output pump at 85lph (12v @43.5psi), so I decided to upgrade the old fuel pump since I had a spare 2020 OEM STI pump on hand from another build. The replacement stock STI pump is rated for ~180-190lph (12v @43.5psi) and operates much quieter and feels smoother across the power band now.
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Last edited by subarukenny_d on Sun Dec 31, 2023 2:06 pm, edited 2 times in total.
2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Electrical Aspect of the Swap:

Overview:

Harness definitions -
What is each harness and what does it do?

There are a few harnesses in the vehicle that we reference in this write-up. Starting at the front of the vehicle is the “Front Harness”. This one routes along the bottom of the front radiator core support and over the driver side inner fender arch before terminating just inside the grommet behind the dashboard. The next harness is the “Engine Harness”, this one can be disconnected near the top of the bell housing and routes along the top and sides of the engine connecting all sensors to one location. Moving back is the “Bulkhead Harness” this harness is what everything connects to, and is arguably the most critical of them all. This one connects to the front harness, routes through the firewall in multiple locations, and also connects to the rear harness which leads to the back of the vehicle, this one is considered the “Rear Harness” which routes along the passenger side bottom door frames and leads us to the critical functionality of components in the rear of the vehicle such as fuel pump, signal lights, etc.

What wiring needs to be removed from Donor?

The simple answer here is “all of it”, which is what I did and I am glad I did. You will be reusing or trimming every harness you pull from the H6 outback. You will need the following from the donor car for a successful swap, Front Harness, Bulkhead Harness, Engine Harness, Rear Harness. All will be used, the rear harness will be thinned out and spliced into the Baja rear harness to retain functionality of those components in the back.
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Swapping Harnesses into your Baja:

The best way of going about this is to remove everything from the donor first, that way you can lay it out on the floor, identify connections, and it is all ready to reinstall right back into your Baja. Another way to approach this is to remove the harness in your Baja just to replace it with the H6 straight away. As mentioned above almost all wiring will be used for this swap.

If this is your first swap and can not easily identify the different connectors use labels and tag your connections and bag/label all hardware.

https://www.amazon.com/Pieces-Marker-Se ... TIQAvD_BwE

Ignition Cylinder and Keys:

Keep your stock ignition cylinder, steering column, steering wheel. Virtually all wiring at the end of it will plug directly into the H6 Bulkhead harness. This way your keys to open doors, start the car are all original to the Baja. Both Baja and H6 Outback do not have immobilizers or any chip keys so this keeps things simple. You can just use the outback key fobs or program yours to the keyless entry system with ease - no dealer involvement here. Reference below link to accomplish this.

https://www.youtube.com/watch?v=gIZWESJZ1hw

HVAC & A/C Functionality:

Since my Baja is a vehicle my wife and I use for overlanding/camping a big requirement was to retain A/C. You will need to swap over just about all components from the H6 donor car (except the condenser) including the following: EZ30 compressor, suction & pressure lines, pressure sensor attached to A/C filter/dryer (located on passenger side strut tower), blower motor box, heater core, and electronic HVAC controls above radio stack. This is a good time to replace all O-rings as they are likely 20 years old and will leak when you go to recharge the system. Note that the capacity DRY is 3oz PAG-100 oil, and 21-25oz R134A refrigerant charge. There will be some residual oil in the system, its a good idea to replace the filter dryer beforehand and pull a vacuum on the system to boil any moisture off before charging.
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Retaining functionality of Cargo Lights and Sport Lights:

Since the H6 Outback Bulkhead harness is not pre-wired for the functionality of these additional systems you will manually have to add them in. The way I decided to go about this was to add completely independent fuse protected relays that use a switched signal to trigger the relay and power up the cargo light and the sport lamps. This option still retains the factory switches and has separate power wires routed to where a lot of the other merged wires were spliced into the Baja rear harness. Both of the relays used constant 12v power so they can be switched on completely independent of the ignition cylinder position. This bypasses the E-Brake up requirement how the factory
Sport Lamps are wired into the chassis - due to DOT requirements. I followed the guide below for both Sport Lights and Cargo Light above the bed, there is a nice wiring diagram, ref post #1.

https://www.rs25.com/threads/diy-wiring ... ts.171650/
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2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

EZ30 Manual Swap Wiring Information:

If you are manual swapping (unlike me), the TCU is unused and you will make additional wiring changes. You must wire a vehicle speed signal to the cluster/ECU, connect the neutral signal to the safety switch at the clutch pedal, loop the neutral starting circuit at the shifter harness, run reverse lights and make cruise module changes. I created a H6 swap specific document that will aid in this wiring that will need to be completed to retain functionality of most things in the vehicle.

Use the second half of this video in order to wire reverse and neutral safety switch.
https://youtu.be/G8ueD_M87qM?si=cPQvKezGObg7Fb1m

https://www.subyclub.com/topic/13529-ho ... ped-gen-3/
H6 Manual Swap Wiring Diagram.JPG
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Airbag & ABS Systems Wiring info:

For this part of the swap there is probably the least amount of work to do here. What I did and have zero issues with either system plus both still retain complete functionality is to do the following. The ABS system is pretty easy, front ABS wheel sensors plug right in, they are located at both front strut towers, for the rear you can unplug and pull the grommet through the floor, then just simply plug them back in similar to the front - no splicing or cutting here. In my case the ABS pump/module in the engine bay did not need to be swapped, I just plugged the massive H6 connector in and everything worked as normal with that which was a sigh of relief, no bleeding brakes!

For the Airbag system it can be a little confusing at times but to simplify it just reuse all airbag wiring (easy to spot as its bright yellow wiring) and reuse the original Baja airbag module/airbags. Some of the wiring is physically attached to the dash bar - leave it alone and reinstall after the bulkhead harness goes back in. The Baja and Outback systems are different in architecture, some of the differences are that the H6 Outback airbag system has additional side impact sensors and airbags in the tan seats that the Baja does not have. So if you start mixing parts/airbag modules it will likely throw a light as it is looking for sensors that don’t exist etc.

What I did was reuse all my original Baja wiring, airbag module, airbags for the driver and passenger side and all functions as before with no lights or codes. One thing to note is that the airbag connectors are a royal PITA to disconnect. It is a 2-stage clip where you usually have to slide a pin over and depress to release the clip. When you come across one for the first time you'll understand my point I am trying to convey, do not break them as they are difficult to repin/replace. If you do have issues with your swap codes can be pulled from the ABS and airbag modules, usually just a connector you forgot to plug in.

Repinning Connectors:


This is a common practice for swapping plugs over from one harness to the other without cutting/crimping/soldering any wires. This can be done for the Wiper motor under the cowl, rear window connectors, sunroof and map lights connector at the passenger side A-pillar.
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Dashboard and Interior Pieces:

Physically all interior pieces you’ll have to remove will go back into place once you have the wiring part of the swap completed. This includes removing the dashboard to access the bulkhead wiring harness that needs to be swapped out. It routes completely behind the dash and feeds through the driver side fender to the fuse box in engine bay, through grommets in firewall to engine bay, and along the passenger side kick panel back to the rear harness. You will also need to swap over the Heater core and Blower motor assemblies as they use the Auto climate controls, and will plug right into the H6 HVAC controls above the radio.

It’s a good idea to “bag and tag” this hardware so you know where it came from and where it goes back to. This helped me tenfold with my swap when I switched gears to the “reassembly” aspect of the swap.
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Last edited by subarukenny_d on Sun Dec 31, 2023 2:06 pm, edited 2 times in total.
2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

The Dreaded Rear Harness Merge:

A friend of mine was able to pull a 2003 Baja N/A rear harness that was mostly plug and play with his 01-02 H6 engine swap. This may be easier and something to consider - however I used my 05 Baja harness and made everything worked out, maybe with some extra time invested into this part because of the merge.

This is basically the most time consuming part of the wiring on the swap, and usually wires are merged at the rear seat near the fuel pump hanger access panel. But if you are feeling creative and want to merge at a different spot - be my guest lol. This encompasses making the H6 rear harness work nicely and function with the baja harness. Both will be “chopped” and spliced back together to create one uniform harness again that is a blend of two separate harnesses. A trailer brake light converter that accepts “Stop” and both “Turn Signals” is required because the Outback has separate bulbs for brake and turn signal, whereas the Baja has 1 lamp per side that does brake lights and turn signals all in 1. Thus the converter allows the inputs for the brake light and both turn signals. Keep in mind it is smart to tie the turn signal wires for the trailer brake light module BEFORE the converter. This way you are not trying to convert a signal twice for the trailer lights. I also had a weird feedback issue with the turn signals dimly illuminating on the cluster when I stepped on the brake. After installing LED tail lights and LED turn signal relay (attached to the steering column) all that went away and the turn signals operate at the normal speed - no hyper flash here.

Follow the below excel file that outlines what each wire color does and its functionality. For the most part, wire colors will match the H6 Outback harness and the Baja rear harness. I found that almost all wires were easily definable except the EVAP wiring, these had different colors and needed to be tracked back to the connector by the charcoal box to determine what does what. Some wires share the same color combinations but different functionality so the best way to diagnose what wires purpose is to test continuity and back track. Factory Service Manuals (FSM) are your best friend, follow the link below and download the FSM for both your specific year Baja and donor car, the electrical portion is very useful when troubleshooting.

https://sl-i.net/FORUM/showthread.php?1 ... el-USDM-EU
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2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

What Gauge Cluster Do I keep?:

This is completely up to the user, the stock Baja cluster will physically plug in and work however the Tach will read 1.5x higher signal since the increased amount of cylinders of EZ30D and some warning lights may/may not illuminate. The best compromise here is to just run the H6 cluster that came with the H6 harness or you can get fancy and swap over the gauge faces from your factory Baja cluster to the circuit board/frame of the H6 cluster. This works because both gauge face scales 0-120mph and 0-7k rpm are the same between both clusters. Once swapped over you still get the yellow needles and font of the baja original equipment but functionality of the H6 cluster - Best of both worlds! I ended up locating and wiring up a UK Black Face Meter that works well with my H6 swap. The full write-up on how to wire and install this cluster can be found here:
https://sl-i.net/FORUM/showthread.php?1 ... 2015-01-09
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Tuning the H6 ECU:

Overview:

The 01-04 EZ30D ecu can be tuned and custom tuning is necessary for manual swaps. A manual H6 will run without tuning but will have stalling issues. I will not be going too in depth for this because others have already done this and documented it. In short, the image/rom can be pulled off the ecu using Opensource software and a Tatrix cable. Map can be modified and flashed back onto the ECU. Keep in mind that 01-02 ECU’s share similar structure and 03-04 ECU’s share similar structure. The difference here is the fuel pump controller, 03-04 has it and 01-02 does not. The maps between these 2 timeframes are not interchangeable.

Target Idle, ignition timing, some fueling maps, etc can all be adjusted using this software which is a nice addition being the 2.5 N/A ecu can not be modified without the use of a piggy back unit or standalone ecu.

https://github.com/GCornman/EZ30D-Definitions
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H6 Swap Conclusions:


This is not my first Subaru specific engine swap, I have done several of these so in some regards it became easier the more you do them. However, this should not stop you from doing the H6 engine/driveline swap into your Baja. Some aspects of the swap can be challenging at times but the Baja and H6 Outback share such a similar chassis and wiring design from the B pillar forward that a vast majority of connectors are plug and play making the swap that much easier. The biggest drain would be time, this swap can be very time consuming but once you fire it off that first time is a very rewarding feeling. Additionally, Jake, Travis, and I did not have a write up such as this to follow, so your life should be easier following my write-up and Jake’s videos. The added torque is fantastic for when I load on the rooftop tent, bed full of gear, and the already bulky A/T tires and 2” lift. I hope this write up will help any others looking to accomplish what I did here. If you run into any issues not covered here, join the Six Swapped Subarus FaceBook group. The community is awesome and always willing to help!
2005 Black/Grey H6 Baja Sport A/T

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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Attached below are the snips of the Excel file I created when merging the rear harnesses together, please note that there are 2 separate diagrams specific to the 01-02 H6 and the 03-04 H6, please make sure you are using the correct one or it can get confusing. I did my best to decipher both FSM's, these may not be perfect but will get your swap going in the right direction. See below:

01-02 H6 Outback Wiring Diagram
Baja Rear Wiring Conversion 01-02 H6.png
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03-04 H6 Outback Wiring Diagram
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Last edited by subarukenny_d on Sun Dec 31, 2023 1:00 pm, edited 1 time in total.
2005 Black/Grey H6 Baja Sport A/T

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subarukenny_d
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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Update #1:

Auto-dimming/ Compass Rear View Mirror

Finally got around to adding in the Auto-Dimming mirror w/ integrated compass from the donor car. When I completed the swap I repined the bulkhead harness to accept my Baja ceiling/sunroof/map light harness. All Baja controls worked flawlessly, and I read online that all 03-06 Baja's were pre-wired for this upgraded mirror as it was optional from factory. After pulling down the map light/sunroof controls there she was - connector taped up and ready for the new mirror. Physically the mirror bolted right in place of the original manual one, fed the wiring up to the connector, plugged in and works perfectly. I love when optional stuff like this is pre-wired such as this example.

Once installed I noticed that the compass was not indicating the correct direction. To properly calibrate to your specific area use the links below (one is the calibration process and the other is the "zone" map of where you live and what number correlates to that area).

https://www.subaruforester.org/threads/ ... off.56422/ Post #3

https://www.subarumanuals.org/subaru-2985.html

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H6 Engine Skid Plate

This was a bit of a gamble, I previously had the Primitive Racing 3/16" "Rally Tough" skid plate on my Baja designed for the N/A or Turbo chassis. I ended up selling that one and opted to try out the 2001-2004 Outback H6 specific skid plate on my Baja. What makes this so different is the cutouts for the massive H6 catalytic converters. Since I had this brand skid plate on before all the threads/mounting locations threads were all clean. If you are installing a pan for the first time and happen to live in the northeast be sure to chase the threads of these mounting points, iirc its a M10x1.25 tap to accomplish this. Hardware provided with the skid plate will spin in by hand without any hesitation - nice. This will replace the factory plastic splash tray if you have it still, (mine was long gone). In the past I have heard some pretty audible rock strikes/dings from debris hitting this pan, would much rather that then smashing my oil pan on trail...Thinking about getting one for the rear diff as well. Primitive makes a very durable, well engineered product. I specifically waited to mount this one up till I knew all hoses were tight and there were no fluid leaks.

H6 Specific Skid Plate Link: https://get-primitive.com/product/armor ... utback-h6/

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Badges

You've gotta add the H6 badging to your Baja after all this work! I used a head gun on the back side of the Outback trunk to get the 20 year old glue loose. Then heated the front as well on low setting on the heat gun. Used a thin plastic panel removing tool to slowly peel the badge off without breaking it. Once lifted I brought the badge inside to warm up, peeled the old glue off, and reapplied some 3M automotive double side sticky tape I had while carefully trimming around the letters and numbers. Lined it up and stuck them on the Baja - swap complete!
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Last edited by subarukenny_d on Sat Jan 13, 2024 10:35 am, edited 2 times in total.
2005 Black/Grey H6 Baja Sport A/T

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subarukenny_d
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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Update #2:

Took the H6 swapped Baja on the first long drive far from home, my buddy bought a 11' WRX that needed a motor so we headed down the Philly to grab a JDM EJ20x to swap into his newly acquired chassis. For what it is you cant beat the price of these motors, its a good budget alternative to any $$$ usdm motor. Loaded it in the Baja with ease, barely clearing the cap! Strapped it down and headed back home, these little Bajas are fantastic for small jobs like this. Thankfully this long trip was uneventful - however this trip did outline the need for an alignment. On this tank I did some local driving and highway, I averaged about 21mpg with the meaty tires and engine in the bed.

Link to his 2011 WRX engine swap video: https://youtu.be/15pw5BxUSvU?si=uW7iO8jsQg0cNUTY
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HVAC Color Conversion

Another thing that was bothering me was how I converted all the dash lights to white LED's including the switches, aftermarket radio, new to me UK BFM cluster but the only thing I was initially unable to change was the H6 HVAC display - which was green...Yuck! After posting on the H6 facebook subaru pages I found a guy who has the tinted glass to change the output color to a variety of different ones. He offers a pre-cut in my case "rose bronze" tinted acrylic that once put in place makes the lights pretty close to white. I'll take it!

Keep in mind he uses tinted acrylic and film to alter the light color. Mine was all in the pre-cut acrylic.
A similar DIY write up can be found here: http://forum.liberty.asn.au/viewtopic.php?f=10&t=35925

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Last edited by subarukenny_d on Mon Apr 22, 2024 5:49 am, edited 5 times in total.
2005 Black/Grey H6 Baja Sport A/T

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subarukenny_d
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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Update #3:

Custom Catback Exhaust

If you refer to my exhaust section above I outlined a couple options/routes you could take. I went to autozone and got a cheap 45* turn down pipe to get me by for a bit after the swap till I decided what route I wanted to go, with just a muffler delete it sounded okay...but like it has a massive exhaust leak while driving. Ultimately I decided to just have a local muffler shop fabricate some 2.5" OD piping to mount the magnaflow 2.5" offset 4x9 muffler up and while he was in there deleted both the front round resonator and the rectangular boxy one in the back. Even with both resonators deleted going straight to the muffler it has great tone, not overly loud by any means, and zero drone while driving. Its a good "quick and dirty" exhaust to get me by the winter till I decide what I want to do with the stainless headers + custom stainless catback exhaust. That whole setup would be Tig welded and pie cuts most likely..

Sound clip here: https://www.youtube.com/watch?v=nS7yPvzvAHQ

Ignore the road salt, it's winter in PA :roll:
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Last edited by subarukenny_d on Sun Jan 28, 2024 11:03 am, edited 2 times in total.
2005 Black/Grey H6 Baja Sport A/T

Follow @Subarukenny_d on instagram for Baja updates
subarukenny_d
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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Update #4:

External Transmission Oil Cooler

I installed an upgraded external Transmission ATF cooler Doorman Part #:918-287, because I do tow with my Baja I prefer to keep the transmission happy and cool the ATF fluid down as much as possible. I have the external oil cooler routed in series BEFORE the radiator cooler. This is a critical step because if you live in a colder climate like me in the winter you still want the fluid to become up to operating temperature or the transmission will not shift smoothly - completely eliminating the radiator cooler/warmer out of the equation is not the best which is why I installed this way. In conclusion using most of the stock routing the hot fluid comes out of the transmission, to the external oil filter housing in the driver side fender, then from there to the aftermarket external cooler, then to and across the radiator, and finally back to the hard lines back to the transmission.

Doorman External Oil Cooler I used: https://www.amazon.com/dp/B01D8VLHI6?ps ... ct_details

Link to the write up I found and followed for this installation: https://www.subaruforester.org/threads/ ... 574/page-6
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Ditch Lights Install

Always wanted to install ditch lights for off-roading. Was looking into these pod lights and found they are VERY pricey for what they are. After doing a bit of research I found a set on amazon that have been working well for me so far, no condensation or water intrusion so far, and the lens's swap out easily. The light kit installed easily and was mostly plug and play wit the exception of power and ground. Kit includes all wiring and relay kit. As for mounting brackets I went with ones from ADF, the bolted under the hood attachment points and provided the mount for the pod light. I used longer flange bolts for the hood attachment points and a shorter bolt for the pod to bracket mount.

AUX Pod Lights: https://www.amazon.com/dp/B0CJF38XY2?ps ... ct_details

ADF Ditch Light Brackets: https://awdadventure.com/products/2000- ... JcQAvD_BwE
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Last edited by subarukenny_d on Mon Apr 15, 2024 8:17 am, edited 3 times in total.
2005 Black/Grey H6 Baja Sport A/T

Follow @Subarukenny_d on instagram for Baja updates
subarukenny_d
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Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Reserving this reply area for project updates.
2005 Black/Grey H6 Baja Sport A/T

Follow @Subarukenny_d on instagram for Baja updates
subarukenny_d
Scoobytruck Lurker
Posts: 16
Joined: Tue Dec 26, 2023 7:58 am

Re: H6 EZ30D Engine Swap Into the 2003-2006 Subaru Baja

Post by subarukenny_d »

Reserving this reply area for project updates.
2005 Black/Grey H6 Baja Sport A/T

Follow @Subarukenny_d on instagram for Baja updates
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