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Luke's BH9 Outback - EJ251 Turbo

43K views 173 replies 13 participants last post by  scruff3333 
#1 · (Edited)
This is the story of my Rev D 2.5 manual 2003 Outback BH5. It has 423,000km and looks the part.

This car will take over daily duties from my GF8 so I can repair the rear end damage.

My parents bought this car second hand in roughly 2006 to replace an old Mazda 626 wagon. It had about 100,000-130,000km on it. Since them they've put another 300,000km on it. In the 13 years of ownership the only mechanical failure was the clutch at 300,000km. This car has had battles with several kangaroos and wombats and lived to see another day. It has hauled cows, sheep and alpacas and much more in the boot. It burns oil like a 2 stroke and it still won't die.

As it has reached 423,000km it has been retired into my hands.

Mod List

Engine
  • Twin Scroll Equal Length Headers (Unknown Brand)(Wrapped in Heatwrap Tape)
  • Twin Scroll to Single Up-pipe (Unknown Brand)(Wrapped in Heatwrap Tape)
  • 57mm (2.25 inch) Intercooler Piping
  • Front Mount (65mm x 180mm x 550mm)(2.5" x 7" x 21.5")
  • TD04 off a 2004 WRX Sedan (EJ205)(Using 5-6 PSI Wastegate)
  • New Age Alternator Cover
  • Custom 2.5" exhaust
Handling
  • Front Sway Bar off a GC8 WRX Wagon
  • Front Sway Bar off a GC8 WRX Wagon
  • 316mm 2 Pot Front Brakes off a 2007 Spec B H6 Wagon
  • Koni Front and Rear Adjustable Struts
  • Gen 4 GT Springs
  • B4 Rear Sway Bar
  • Liberty (Legacy) Rear Bumpstops
Internal
  • Black Leather Front Seats off a 2000 Liberty Sedan
  • Black Leather Rear Seats off a 2000 Outback Limited (Not Originally from that Car)
  • Leather Armrest off a 2000 Outback Limited
  • Leather Door Cards off a 2000 Outback Limited
  • Sony XAV-AX100 Head Unit
External
  • GT-B Legacy Hatch and Wing
  • Rev D Turbo Bonnet
  • Front and Rear Spats
  • JDM Legacy Center Garnish
  • Custom Outback Grill
  • OEM Rain Guards
Wheels
  • Advan RG1's 17x7.5 +45
  • Bridgestone RE003 235/45R17

Engine Management/Support
  • Project Lambda
  • Bosch 3 Bar Map Sensor
  • AEM Air/Fuel Gauge 30-4110
  • Aem Boost Gauge 30-4406
-------------------------------------------

Stock Options Equipped

Engine
  • EJ251
  • 5 Speed Manual Low Range Gearbox
Exterior
  • JDM Headlights
  • Front Fender Indicators
  • Clear Rear Indicators
  • AUDM Bumpers, Wheel Arches, Sideskirts and Door Panels (All slightly different from the USDM ones for reasons I guess)
-------------------------------------------

Components Replaced. Either as Listed Above or Due to bad Condition
  • Front Bumper
  • Front Seats
  • Rear Seats
  • Glove Box Cover- Radio Trim
  • Rear Cup Holders
  • Door Cards
  • Boot Scuff Panels
  • Spare Wheel Cover
  • Mirrors
  • Rear Tailgate
  • Tailgate Center Garnish
  • Drivers Fog Light
  • Subframe
  • Steering Rack
  • Radiator Cap
  • AC Tensioner
  • Drivers Sun Visor
  • Carpet






Luke :)
 

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#150 ·
Cause I'm an idiot. I did it to hold the rotor on properly for when I was testing the clutch/gearbox/drivetrain.

hey mate car is sitting nice, i need that suspension setup!
It's a Gen 4 Liberty setup with the front top hats swapped to Gen 3. Koni struts with GT springs. I'd assumed that you don't need the koni struts to get the stance
That ECU sticker is the same as mine but I had to take the cover off and look at the actual chip inside. There will be a chip starting with "WA...."
Mine was a "WA12212920WW", other chips that are supported end with 940WW and 930WW, but there might even be more now days.
Next time I'm home I'll take the cover off to confirm if it has the same number. I'd think so as they are both Rev D cars
How did it sound with that exhaust? I found a BE5 rear muffler on ebay last week (the type that had the bi-modal valve thing), $95 delivered! Had to modify the hangers a bit to get it to sit right then extend the tip as it was about 120mm short. Plus the flange on it necks down to 2", rest of the piping is 60mm.
Wow that's way cheap. It sounded pretty good but it's still louder than it'll be later due to the unplugged O2 bung. It doesn't have the full iconic Subaru rumble due to the ELH but still has a slight grumble to it. I'll upload a drive-by video next when I get the chance to film one
 
#149 · (Edited)
hey mate car is sitting nice, i need that suspension setup!

That ECU sticker is the same as mine but I had to take the cover off and look at the actual chip inside. There will be a chip starting with "WA...."
Mine was a "WA12212920WW", other chips that are supported end with 940WW and 930WW, but there might even be more now days.

How did it sound with that exhaust? I found a BE5 rear muffler on ebay last week (the type that had the bi-modal valve thing), $95 delivered! Had to modify the hangers a bit to get it to sit right then extend the tip as it was about 120mm short. Plus the flange on it necks down to 2", rest of the piping is 60mm.
 
#152 ·
So I haven't had much time to do stuff on the car but here's what I have done.

Somewhat unrelated. I (well Mum) bought a Brumby (Brat). Only 424,000 km (260,000 miles)on it which is the same as the Outback. Picked it up for $1200 AUD ($815 USD). It has been my Mum's dream car so hence why she looks pretty happy with it. I might start a new journal on it if people are interested in the fixing of it.



Back to the actual car. I bought a USB extender to install the USB from the back of the radio in a cleaner way.



Despite what it looks like it is actually straight.



Finally did the breather port into the intake. I still need to JB weld them in but didn't get around to it.



Also cut the fender liner to clear the intercooler piping. I'm not sure if I'll box this in or not at the moment.



Installed the front spats. I still need to secure the underside but I only remembered how to do it once I was back in Sydney.


Also picked up an AEM AFR gauge for $70, still had the protective wrapping on it. It didn't have the sensor so $45 on eBay got me a new Bosch sensor, which arrived today. So that cost me $115 instead of the $300 I was going to spend.



I also got the front end buttoned up and tested all the lights, so that's all working now. I managed to pick up some dash lights today too as I blew a headlight in the GF8 and had to get lights anyway.

The other week I emailed Project Lambda Tuning and found out they won't have the Blue SSM in stock until late this month or early next month so that's a bummer but at least I can save for it in the meanwhile.
I finally think got my head around the VE map and will start making a rough base map for boost next week. Also think I understand timing now. From what I've seen you pull around 1-1.5 degree of timing for every pound of boost the engine is seeing??

I've only got a day this weekend to get work done at most so I'm hoping to get the AFR wired up and the gauge lights replaced. Maybe more but I'll see how I go. And I probably should make the airbox at some point as I keep putting it off.

Thanks for reading
Luke :)
 
#153 ·
Just another boring update. I managed to figure out why I was having a high rev at idle. I had a leak in the brake booster vacuum hose. So every time I put my foot on the brake it would jump up 200 rpm and not go back down. This would happen until about 1900 rpm. I ended up testing the one off my Impreza to see if it was the issue and not the booster leaking, which would have really sucked.

Finally finished the grill construction. Needs a brace at the back and paint but it's installed for now. Ignore the badge being upside down. I didn't notice that until I looked at the images after.





I managed to pickup some OEM (I think) rain guards for $20. Also replaced the drivers side window seal as it was ripped.





I wired up the AFR sensor and gauge. It's in a temp locations but I'm thinking a metal plate in the recess with the AFR and boost gauge would be nice.



I also started a base map for the Volumetric Efficiency and the timing. I'd love some criticism as Ive only learnt what I have so far from random sources on the internet and I have no idea if I'm even heading in the right direction. So it would great to know that I'm not stuffing the engine up straight away.




This week I've ordered the Blue SSM and the Project Lambda License so that should get here in the next two weeks. Also ordered the bolt on 3 bar MAP sensor. So yeah tuning isn't far off. I'm hoping to get it engineered and register around late November/early December.

Thanks for reading
Luke :)
 
#156 ·
Yeah not my greatest moment. Luckily it was only held on with masking tape.
You'll end up with way higher VE values than that. I was at 100 from 94kpa and 4400RPM with the stock injectors. A part from that I cant help you much more yet. I'm also trying to make a spark map too. I'll send you a copy if you want to compare?
I'll play around with it a bit more during the week to adjust to a higher value. At the moment it's a really conservative base tune as it's easier to up the values than it is to swap an engine. Yeah I'd be keen on comparing as the more resources I can see the better.
I used this to guide me a bit with the base map.
VE Tuning Basics - Official Haltech Forums
Which map sensor did you get?
I ended up getting this one.
Bosch Map Manifold Air Pressure Turbo Sensor For Vauxhall Opel Fiat 0281002437 | eBay
This was the one that you suggested like 6 months back. I've used the scalar amount you suggested for it too.
 
#157 ·
Sweet, that map sensor is still working good for me. Did you mean using the offset and slope figures I suggested?

I ended up using the load and airflow scalars (for the 560cc blue injectors), from the website and they are working fairly good too.

Don't be worried about about going higher with the VE values at first. Going rich is much better than going lean!

Hatecrew's post #234 sounds like the best plan to me so far. Its also talked about here and also by HP Academy's tuning videos too. Have you watched their webinars yet??

MegaSquirt EMS Engine Tuning Information - DIYAutoTune.com
 
#158 ·
Sweet, that map sensor is still working good for me. Did you mean using the offset and slope figures I suggested?
Yeah that what I meant on that. That's good. I was umming and ahing about just getting a cheap one but I ended up getting a Bosch genuine one which I'm glad about.
I ended up using the load and airflow scalars (for the 560cc blue injectors), from the website and they are working fairly good too.
That's awesome. I still have the WRX 440cc injectors laying around as a future upgrade. How did you end up installing your injectors?

Also I have a fuel pump out of an EJ255 Forester that I've got to install at a later time. Is any scaling need for the higher flow capacity?

Don't be worried about about going higher with the VE values at first. Going rich is much better than going lean!
Thanks for that. For some reason I though going a lower percentage was better. I've now thought it through and actually looked at how the formula works and that makes sense. I'm currently upping that VE map. It's hard as I don't have any feedback from the car to know what the changes I'm doing do.
Hatecrew's post #234 sounds like the best plan to me so far. Its also talked about here and also by HP Academy's tuning videos too. Have you watched their webinars yet??

MegaSquirt EMS Engine Tuning Information - DIYAutoTune.com
In regards to the disable o2 sensor mentioned is HateCrew's post is that for closed loop? What exactly does that do?

I haven't watched the videos yet but I've had their ads showing up from months.

That link you sent is great. I've had a read through and it definitely won't be the last time.

Are you able to send across your file and I can send you mine?
 
#159 ·
Sorry for the ton of images in advance. Got a bunch of stuff done hence the long post below.

On crjohnson's comments I redid the VE map to be much richer. I'll see how that goes one the BlueSSM arrives. I'm also going to compare it to crjohnson's map and make changes accordingly.



I had some hose heat shielding arrive so that went around the oil drain line. In the process the fitting in the valve cover broke clean off so I had to fix that. I also fitted some of the left over hose to the brake booster vacuum hose as it goes over the turbo.



I got around to JB welding the breather ports on the intake. This is now painted wrinkle red



I made a mockup of the gauge plate to go in the car. I ordered the boost gauge today which will fit in the other side of the plate.



I had run out of things to do to avoid the airbox so I tackled that next. This was done first with a cardboard template in project binky style.

Main piece cut out.



Bent and test fitted. Another hole had to be cut for the intake.



Next was the lid. Again started with a cardboard template, then cut out of steel.



Bend and test fitted over the filter



The box was then cut to suit the profile of the lid.



Then you make some brackets for the lid to bolt onto



Brackets riveted in place.



Again cardboard template then steel. This piece is for the notch around the brake lines at the bottom.



Then bend into shape ready to be fitted. (yet to be fitted though)



So this is an overall photo of it in the engine bay, This was taken before completing the lid and brackets. I've used the factory intake as I had it and it looks better than anything I could make.



And here's a closer shot of the airbox with the lid secured. It's not fully in place here either as the brake bais valve clamps the airbox against the strut tower.



I still have to join the lid to itself, mount the lower piece shown above and have to make a piece to seal the lower inter-cooler. I thinking I'll paint it a charcoal colour with a hammertone paint as the silver is to much for me.

I'm currently waiting for the project lambda software and map sensor to arrive so hopefully they'll get here soon.

The list of jobs left is getting short.
  • Finish and paint airbox
  • Make the gauge holder and paint
  • Paint the underside of the bonnet in satin black
  • Plastic weld the front bumper to accommodate the intercooler
  • Stick up and install the replacement steering wheel
  • Install the boost gauge (when it arrives)
  • Tune car (when that stuff arrives)
  • Paint car (aiming for January)
The cars in for an alignment/lookover at the mechanic on the 11th of next month and them hopefully engineering in early December.

That's all for now,
Luke :)
 
#160 · (Edited)
So I figured I should get round to updating this at some point.

I painted and finished the airbox. I used my damaged GF8 hatch rubber liner to act as insulation between the piping and airbox





Finished view of the engine bay. At this point the only things left were the MAP sensor and boost gauge.



I relocated the cigarette lighter the the center console as the gauges block the way. I annoys me that they don't look level, but it's not as if you can see them anyway.



Here's the CAD template for the gauge holder



Here's the metal, cut. bent and painted.



And here's the final product. Not half bad. The gauges are level, it's just the angle making them look weird.



The gauges have been installed with a custom wiring harness that allows them to be turned off with a spare fog light switch placed next to the microphone. I've done that because it's easy to do now and will make life better when driving at night.

I also installed the Bosch map sensor.

Here's a comparison of the new (left) and old (right)



When I first installed it air was leaking through due to voids in the sensors design. I filled it with JB weld and filed it down smooth. No more leaks.



I've loaded crjohnsons base tune onto the car and it runs fine.

I'm currently not getting much boost. It will spike up to 3psi max but that's at full throttle while driving so I definitely have a boost leak. I'm hoping it's just the waste gate not having the right preload due to me changing it to a lower psi one. It's weird though as the turbo flutters like a VL Commadore but it's just not buidling boost.

In other news I drove it to the mechanic the other day (15km) and it had to issues driving (except for no boost). Apparently there's a slight power steering leak (power steering isn't my friend atm) but everything else mechanically is fine. For some reason none of the windows now work which is great given the air-con doesn't work great either.

This weekend I decided to have a break from the car as I was just over it. I'm a bit over cars in general at the moment. The power steering fluid in my Impreza decided to drain itself onto the headers last Monday (power steering still works so I'm not sure where the fluid came from) so between that and no boost I was just over it all.

I also decided to remove the deadline for getting this car on the road (end of the year). I'd been pushing myself pretty hard on getting stuff done because I can only work on weekends, even though it may not look like it and it all caught up with me and above is the result.

Anyway thanks for the read. If anyone has ideas on the boosting issue it would be great to hear it.

Luke :)
 
#162 ·
It felt faster than my Impreza for sure, but the outback has slightly more HP per ton (117.4 hp per ton for the Impreza versus 122.2 hp per ton for the Outback) in it's stock form. But I'm sure it's faster than it was.

The car did run a bit lean when I got on the throttle but I think that because it's not getting boost, so it's ending up in an area of the VE map and isn't fully refined yet as it's not a common place for the engine to be.
 
#163 ·
Adding boost should only lean it out more. Don't forget that tuning for cruising and medium load is just as important as wide open throttle. Unless you were driving at like 5000RPM+ (which I wouldn't recommend just yet without data logging and watching that knock sensor), then you might only hit 3psi at light loads pretty often so you'll want the AFR and spark dialled for these areas.
 
#167 ·
Hello all I'm still alive.

Sorry for not updating. Life has been hectic since the start of this year between the bush fires hitting us, a breakup and COVID. But work on the car has gone on.

So this is what I've been up to with the car.

So I started stripping it for sanding the day after Christmas, but that stop not long after due to the bush fires. Our town was lucky and we only lost around 15 homes, and my family only lost the woodshed and back fence. Fortunately the car had been moved to a slightly safer location during this. It actually made the local facebook group as someone was concerned it was stolen as they'd spotted it when my dad drove it to the other location.



So I didn't end up starting the sanding until late January due to all this. Turned out the passenegr side was a nightmare due to the previous paint job.



As it got to the back door on the passenger side I gave the car a power wash. This revealed that the entire door was cover in bog as it just fell off. I have no idea why this was done as the door was straight underneath.



Luckily the local wrecker had one in the same colour so $80 later I had a new door.



Other side of the car here featuring my wonderful hand print.



I'm going to give a shout out to audiobooks as they are what got me through the sanding. I think I listened to 60 hours worth of books while sanding and it was basically the only thing that kept me going some days.

I haven't added any photos from the painter as they were very low pixel and don't really have many photos of the progress as I finished sanding its not that interesting.. Next step the painter just primed and blocked the car. It ended up painted in Holden Monaro Metallic Red and the cladding BMW Dolphin Grey.

These photos are straight off the gun.





Then the painter let the car bake for a couple of weeks and then buffed the whole car. I ended up taking 3 days off work to put the car back together as work was quite at the time. But it only took a day and a half or so.

Car newly arrived. I did like it without the roof rails but I think they needed to be there as it was part of the identity of an Outback.



All back together with exception of the spats.



I didn't mention it before but I completely remade the area around the front mount on the bumper so it looks like the bumper was never cut. I don't have any clear pictures of it though. Also front and center is the custom grill. I think the VA STI badge looks much better than the stock one too



And a clean engine bay picture for good measure.



2 weeks later I waxed it and the car looks amazing.



So the next hurdle was getting the car passed emissions. I failed the first two times and as the round trip was about 300km each time it was a good shakedown for the car.

The things that were issues were:
Rear hatch struts blown (the painted noted this when it got cold)
Clockspring was broken (causing an airbag light)
Rear struts blown and the top nuts sheared off (they disconnect about 20km into the first trip. I noted the car was bumpy didn't know why until I got home and took one of the wheels off)
Major misfire in all 4 cylinders (burnt sparkplugs, I now hate subaru becasue of the spark plug location)
Running way to rich (tune was shit, that's my fault)
Brake booster leaked (would cause the rpm to go up and not down when you braked)
Throttle body would stick open ( caused the rpm to hang at about 3000rpm)

The reason for the misfire was the spark plugs had burnt out and self gapped to 2.5mm. I replaced them with a colder range and the misfire is gone.



I completely re-tuned the car with the help of CRJohnson who has been an absolute legend in getting the car to where it is. This got the car passed emissions and running fantastically.

I replaced everything else listed above and it got rid of the idle issues and ride quality and now the car works fine and I've had no issues since.

This is a photo of the car on the day it passed emissions. The front and rear spats are now installed.




I'm currently in the process of getting the car engineered. I've had to go back to the stock brakes on the front as otherwise I'd need to brake test the car which costs a shit ton of money ($1-2K). The engineer also wanted me to make an addition crash bar due to me cutting the original for the inter cooler. I ended up buying a cheap welder to do this and it did the trick just fine.



So that's where the car sits at the moment. It should be looked at by the engineer and registered by the end of the month and I'm super keen to have it on the road as you can imagine.

I forgot to mention that I picked up a 20mm RSB for $35 and now that's on the car and I replaced the steering rack back to the original as the WRX one leaked like a sieve. Sadly the paint has reacted slightly on the rear quarters and the roof so they'll probably get repainted in the summer but it's not something I'm to worried about and you don't notice until you're up close. This is most likely due to the previous shitty respray.

Currently the car is running 8psi very happily. It spools quick and sounds like a jet engine on boost. The low range torque is crazy too. It's just under 7 seconds for the 0-100km but thats without launching as its the stock clutch.

So to end a picture of a very happy me with the completed car.



If anyone wants more pictures/info about anything let me know as I've tried to keep this post short while covering as much as possible.

Luke :)
 
#170 ·
Probably a hybrid motor next. Looking at doing an EJ22E shortblock, EJ251 Heads and EJ22T head gaskets which will bring the compression down to about 8.3-8.6ish and I should be able to run about 14 psi. I'd need to do the valve springs to stop valve float. But that'll be a while off as I'm looking forward to not working on cars for a while as its exhausting and I've been at this nearly every weekend for the past 18 months and barely taken time off for anything else.

I'd also love to do a 6 speed swap but I'll do when I blow up the 5 speed. Annoyingly enough it's a lot more involved than swapping one into a GC with not being able to get R180 hubs for the rear without going full custom. And technically I already have a 7 speed with the high/low range ability on the stock gearbox :ROFLMAO:. Other than that maybe GD STI control arms in the front to bring the wheels out to fill the fenders better and de-lift the front and rear sub-frames.

Despite the list above there's not really much left to do. It handles better, quieter, faster and nicer to drive in every aspect than my GF8 which was the goal.
None of the above is essential and that's where I wanted the car to be before I got it registered.
Love it man!
Cheers mate
 
#171 ·
Luke,

You took your DIY skills to the next level with this build, I'm amazed. The air box fabrication was just awesome. I have a Legacy with the same EJ251 (with around 240kkm) here in Brazil and I'm starting to plan the turbo install - FMIC, a PNP Speeduino for management (bought a OEM ECU to harvest the connectors and the case), custom turbo (TD04 are not so cheap here, so it's just better to go with a local fabbed turbo), and loads of DIY action.

Being honest, it's quite scary to start a build from scratch with limited resources and counting only with my labour, but seeing your progress not only inspired me, but also gave a taste of the finished product. Thanks for sharing your build with so many details, you can be sure that you helped me a lot!

Regarding your next steps: a BFM cluster really changes the driving experience with these cars, and it's not so hard to do the harness merge. Be sure to look for a Rev D cluster, since the others have some problems with the fuel gauge.

Regards,
 
#172 ·
So I figured I'd update this thread one more time. Sadly the forums aren't what they used to be and I lost my motivation to post and updated so I figured I'd finalize this thread.

After getting the car on the road I did about 12,000km before I got rod knock. This was going to happen as the engine had slight knock already. So I swapped it for another motor which unknown to me had head gasket issue but I managed to be another 12,000km out of it. Sadly between this, and moisture being under the primer which caused the paint to bubble I decided that the cars time was over. So it was parted out and sent to scrap

All in all I have no regrets doing the project. I learnt so much with this car, what to do and what not to do. It helped me realize what my goals were in a car and a project. I've met some of my best friends through it which I didn't have before I started this car.

All that being said I replaced it with another gen 3. I bought a white Liberty (Legacy) wagon with a 2004 WRX swap. It needed a lot of work as it wasn't the best conversion. Since I bought it I have put a long ratio 6 speed in with R180, installed brembos, repainted the front clip, installed a full JDM interior in it, added a bunch of JDM aero bits for it and put 70,000 km on it in 2.5 years.



It still has plenty to do as I'm going to start a wiring loom from scratch and I have to clean up the engine bay a bit but its been a great daily which has been awesome to drive.



Here it is with my mates factory twin turbo B4 and full Trial kit back when I had RPF1's



And this is with my mates EZ30 6 speed Gen 2 sedan.

Now as I can never stop working on cars the week my outback went to scrap (January 2022) I bought a another project car. It is a 2001 Bugeye Wagon which was externally stock as a rock. Had a straight cut 5 speed and a blown 207 motor. Which was immediately all removed. The plan was to EZ30 6 speed swap it. I already had the engine and gearbox for it funnily enough so the plan was to do this swap in the beginning.



Since I bought it I've changed the wheels (my old Outback ones) gone sedan front end on it, installed JDM HID's and obviously done an engine motor swap. As of current it isn't running yet as I have a few wiring issues from the merge I did.



All the engine bay together looking like it could run



This project still has plenty to do but the Bugeye has always been a dream car of mine so this was a good way to have one without having two cars with EJ205's.

So lots has happened since I last updated and hopefully this covers a lot of it. I probably won't do another update on this as it's kind of the end of this thread but I figured a post explaining the end of it all was a good thing to do.

If you want to follow these projects I upload to instagram a bit under lukesbh9 and am always happy to have a chat there.

Thanks for reading
Luke :)
 
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