H6 5-speed swap Subaru

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H6 5-speed
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H6 5-speed swap Subaru

Post by H6 5-speed »

Hello, has anyone in the group done a h6 5-speed conversion? I bought a donor 04 h6 ( no vdc) ll bean outback wagon and plan on swapping the h6 engine and wiring harness into my 03 legacy wagon 5-speed as the host. I know enough that it will all plug and play aside from the manual transmission part, I don’t mind cel lights but want to make sure the car runs, idles, and does not stahl. I know iwire recommends and aftermarket ECU if they do the wiring, I’ve never done car wiring before and I’ve pulled two Subaru engines and put one back in so I have some insight. What all components swap ps pump, ac compressor or lines, hvac control stuff, throttle cables. Much appreciated, I removed the h6 engine yesterday from the donor and half the dash is apart.
mike-tracy
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Re: H6 5-speed swap Subaru

Post by mike-tracy »

I don't think there's any active users who have done the swap. From my limited research, the closer you can get to having 100% H6 parts in your car, the better. In fact that's what I'd do - swap dashes and 100% of the wiring over, as well as everything under the dash. Same thing in the engine bay.
1992 Legacy SS, 5mt and heavily modified
2000 Impreza RSTi Coupe
2003 Baja, H6 and Dual Range 5mt swap
H6 5-speed
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Re: H6 5-speed swap Subaru

Post by H6 5-speed »

That’s what I was thinking figured it should all work, but was trying to narrow down a few things like ac and ps pump, of are hose sizing the same or does the entire thing need changed?
mike-tracy
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Re: H6 5-speed swap Subaru

Post by mike-tracy »

I don't have the answer to that, I would just swap those over (along with the h6 AC condenser) so there's no possibility of conflict. You are in a unique position of having both cars on hand, so you will be able to answer those questions in time. Sorry I couldn't be more helpful.

My experience with H6s and manuals involved a clutch job on an ER27 (Subaru XT-6, aka the only H6 we ever got in the US with a factory manual), helping a buddy do a 6MT swap on his EG33-T (turbocharged SVX motor) in his 98 Impreza coupe. Never messed with the electronics on either of those, though I do intend to buy a low mileage JDM EZ30D and swap that along with a JDM dual range manual trans into my Baja some day.
1992 Legacy SS, 5mt and heavily modified
2000 Impreza RSTi Coupe
2003 Baja, H6 and Dual Range 5mt swap
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anarchy1024
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Re: H6 5-speed swap Subaru

Post by anarchy1024 »

One thing you can try is going to parts.subaru.com and looking up the parts in question for either car, then checking the 'This part also fits' section. If the other car is listed, it's compatible (assuming both cars are in factory configuration). If not, it doesn't necessarily mean it's not compatible, but there's likely something different between the two.

Either way, the best thing is what Mike-Tracy suggested... If the donor car works perfectly, transfer everything from it, even if you may not need to.
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