The mythical flat 6 subaru engine is rather enigmatic to most people and is somewhat out of reach to most Subaru fans, reserved only for the conservative, modest people movers with economic slushboxes and a torque curve made to pull caravans from the suburbs to the big4 of your choice. Despite this, the resemblance to the powerplant from the iconic Porsche 911 and power figures similar to a stock wrx, this engine elicits an unassuming level of pretentiousness which attracts me to implant it in my manual 2003 gen 3 wagon.
I have been considering this conversion since I first bought my car and have been researching h6 swaps and manual conversions and had my eye out for an EZ30D from a gen 2 outback for the transplant. I also had been considering a EJ205 conversion but after alot of deliberation I was swayed towards the H6, one principal reason is being on p-plates so I was keen to keep it naturally aspirated. For about a year I'm pretty sure every H6 outback that went on Gumtree was saved in my watch list until some time in August 2017 I found a burgundy outback from Geelong for $1000 for the complete car.
Ignoring the subtle warnings on the gumtree ad of a blown headgasket, leaking water and overheating in the past, fuelled by my youthful naivety I drove down to Geelong to give it a look. Upon arriving, I laid eyes on the neglected car I was soon to own. Not being discouraged by the huge puddle of water originating from under the motor, nor by the actions of the owner proceeding to fill up the radiator with the garden hose before starting up the car I was adamant it would be mine. I went home after what i considered a successful day and I quickly organised a trailer to collect it the next week. What I forgot to mention was I managed to get the price down to $470 with towing $180, I was full of excitement with this astonishing deal I forgot to mention to my parents that a tow truck would be dropping off a car at the house. They were appropriately livid.
With the new 3.0L outback in the driveway I started stripping down the engine and all the components that I will be needing for the conversion, which is basically the engine long motor and all the wiring from the dash to the front. I also kept some other parts such as the momo steering wheel, sideskirts, cargo mat, front and rear lights. I also managed to install the digital climate control and the blackface gauge cluster which gives the interior a much needed aesthetic upgrade. From the short time the car was running I could tell it was burning water, so I knew the heads would be coming off. With the h6 sitting on an engine stand I started to tear the entire engine down to get to the headgaskets which I replaced, along with all the seals and gaskets in the valve cover and the timing chain front and rear covers. I got the heads machined and I also replaced the water pump and thermostat because I don't think the previous owner has had coolant in the engine for a very long time...
I had been taking my time with this rebuild, just doing it between uni and work and during the holidays so it took me until Jan 2018 before the engine was all together in one piece which was a blessing as at the end of Jan I had my licence suspended for 6 months
I was driving my work van in the city doing 60 in a school zone at 2.32 with no p-plates on and got pinged by unmarked police. Anyway my car was going to be off the road for 6 months which is perfect to take the EJ20 out and commence completing the transplant.
First week of March I moved my car into hibernation in the garage and started disconnecting the engine. I managed to get it out and the h6 in in a day which proved the easiest part of the conversion.
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For the transmission side of things I am using the factory 5 speed manual from my liberty and mating that to the EZ30 via and exedy HD clutch to handle the extra torque. I received some wiring diagrams from Al to show how to get around the TCU situation and wiring up the vehicle speed sensor which is a great help.
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Everything bolts in quite nicely, the bell housing pattern is the same, the engine mounts are the same, the radiator fits with no adjustment which makes sense since it is the same chassis. Hence another reason why this swap I considered would me more straight forward than going down the turbo road.
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