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Convert from Subaru to Lycoming on 9a

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Am aware of very nice 9a with Subaru. Am curious about conversion to Lycoming O-320.

Are there any sources of information about this process?

Key aspects to be aware of?

Major parts needed?

Approximate cost to accomplish a conversion?

Tips to minimize problems and maximize success?

Does this type of conversion make economic sense?

Thanks!!
 
Am aware of very nice 9a with Subaru. Am curious about conversion to Lycoming O-320.

Are there any sources of information about this process?

Key aspects to be aware of?

Major parts needed?

Approximate cost to accomplish a conversion?

Tips to minimize problems and maximize success?

Does this type of conversion make economic sense?

Thanks!!
Fundamentally, you're probably buying/installing a whole new firewall forward setup, depending on how the subaru was mounted. Between a new engine mount, engine, accessories, prop, cowling (?), and miscellaneous items, you're looking at at least $50K, plus several hundred hours of work. Is the Subaru powered airplane priced low enough to make this a viable conversion, or would it make more sense to just buy a 9A that's already set up the way you want?
 
Thanks you! That is the kind of information I’m trying to gather. At what price point would the Subie 9a purchase make sense (for conversion), and yet remain within reasonable market valuation for a Lycoming 9a? I realize there’s all kind of “ballpark” here, but this is helpful for consideration of options at this point. If someone has done this, would appreciate any references to documentation of experience.

Thanks!
 
I think Kyle's "at least" $50k estimate is correct with a good used engine and sourcing a few second hand items. If you can find a cheap core and do your own engine overhaul, modify or fabricate an engine mount, and are good enough with fiberglass to make major cowl mods, you might get below $50k.

On the other hand a new or overhauled engine, new cs prop, and ordering/ waiting for all parts from Vans would put you well North of $50k. Of course if the paint and panel aren't exactly what you want there's an additional cost.
 
At what price point would the Subie 9a purchase make sense (for conversion), and yet remain within reasonable market valuation for a Lycoming 9a?
Hard to say, as it depends in large part on the value and availability of your time - this is going to take a big chunk of time.

Other thoughts:

- Installation of a Subaru is sufficiently off piste that you’ll want to make sure no other unusual innovations are present.

- be sure Vans has the parts you’ll need.

- If you’re looking at this one just because you can’t find a good Lycoming 9A, you may have underestimated the time needed to find a good -9A. It can take a while.
 
Understand that you will be essentially buying or making everything firewall forward NEW.

The firewall itself, and addressing any holes that aren’t where you need them, the engine mount, engine, prop, prop spacer, spinner, engine cowling, exhaust pipes, and a deep dive exploration into all the avionics that interface with the avionics.

Price out these items, and figure 1k-6k for engine monitoring depending on options. You will need engine baffling, a different cabin heat, all new engine controls, every fuel line at least $100 each, you’ll be buying all new everything in the hardware department from someplace like aircraft spruce. It is highly unlikely that you reuse anything FWF, maybe a battery, or a gascoalator.

Are you doing all this yourself? Or hiring an A&P? Do you speak schematics fluently or are you paying $150ish per hour to have that done?

Is this aircraft VFR or IFR? Glass cockpit or steam gauges? There is a huge difference in price between the two. You could buy any of a few low and slow aircraft for the difference in price.

I would look at this as a previously flying project that has absolutely nothing firewall forward. Airframes are cheap, everything from the instrument panel forward is expensive. This project would involve all of that and about a year and a half of working on it.

For about the same money you could be flying https://www.trade-a-plane.com/searc...odel=RV-6A&listing_id=2449856&s-type=aircraft

Looks like a high time motor. If it is still has good compression, not making metal, and still making good power you could probably fly it without issues for a couple hundred more hours.
 
My advice is don't do it. I converted a 6A from an auto engine to a lycoming O-320 for around 15k in 2023. And despite saving money I absolutely did not come out ahead when you factored in time. You need to be patient and piece together parts as they become available used if you have a budget. By far the biggest expense is the engine. I bought a cheap core that I ended up determining after boroscoping was airworthy with minor work instead of rebuilding. You can get deals on the old style nosegear and engine mount since people are converting to tailwheel or upgrading to the elastomer nosegear mount. I also needed an exhaust, a cowl, magnetos, and a prop. The O-320 I bought had been sitting for years and needed gone through, I replaced a bunch of seals, swapped the sump to one compatible with the RV mount, new carb, new fuel pump, etc. I redid all of the avionics at the same time which I didn't count as part of the conversion cost but I did rip out a lot of automotive wiring. If you buy a new engine it will quickly cost north of 50k. I probably could do it for 15k again but it would take months to years of time accumulating cheap parts.

Also, a big note. If your airworthiness paperwork says "subaru engine", I believe you legally have to hire a DAR and re-enter experimental phase I testing again, because an engine change can be considered a major alteration. I was lucky that my paperwork did not specify the auto engine, so it was actually more correct to switch it back.
 
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When looking at an aircraft to purchase absolutely keep your emotions out of the equation. Hire someone to inspect the plane that has no relationship with it. I have seen paint and pretty interior sway far too many and they end up spending a fortune to improve a very poorly constructed plane. The money you spend for a good inspector will pay dividends in the end. As for this plane with a Subaru engine in it, it better be a darn good price because completely building the firewall forward is going to bring you right into or above the cost of a well built flying plane
 
For about the same money you could be flying https://www.trade-a-plane.com/searc...odel=RV-6A&listing_id=2449856&s-type=aircraft

Looks like a high time motor. If it is still has good compression, not making metal, and still making good power you could probably fly it without issues for a couple hundred more hours.
That seems like a really good deal. I'd far rather buy that and spend time and money rebuilding the engine and upgrading the avionics than buying a subaru RV and converting it.
 
Thank you for these considered thoughts. This is why the VAF website is such a treasure. People that are willing to take their time to share their knowledge, wisdom and experience -- without hesitation. This information will be taken under close advisement, and considered in moving forward. If the project is pursued, I suspect there will be further communications, such as "Please remind me why I decided to convert a Subie aircraft!!".

Thank you!
 
What looks like a simple engine swap usually grows into a complete engine change/front mount & nose gear change/complete engine accessory change/complete engine instrumentation change/complete dash upgrade (why not, it's apart anyway), complete cowling mod or replace/ complete repaint.
Wanna be a builder? you'll be one after this conversion.
 
I would highly recommend you not do it unless it is a virtual steal. I did this and it is FAR more than just firewall forward. The fuel system is wrong. The engine management is wrong. Cowling, cabin heat, firewall penetrations, firewall bump outs. This is a HUGE project. Hindsight, in today’s market the plane would be $25k or less before I bought it. The amount of rework is huge. Buy a partially built kit and do it once instead of redoing.
 
Figure the cost for the engine, prop, FWF (engine mount, Elastomeric gear kit), Finish Kit (new cowl and spinner) & probably a replacement firewall. I doubt the mount holes would match the Sub mount holes. Probably the fuel system from tanks to engine including the boost pump. Starter, Alternator, Oil Cooler. I would guestimate North of $75K with current Lyco/Hartzel prices. Then there's potential issues with the instrument panel depending on what the builder installed for the Sub. Add all the work to disassemble and reassemble. Oh my. Maybe if it were really cheap and you need a project.
 
Given it already has water cooling of some sort... maybe some other auto engine conversion? Just tossing it out there!
 
Nice 7A kit on sale below… I’d jump on that LONG before what you are contemplating.
If you aren't really familiar with building things you can probably also add a couple of years of thinking and labor to the project. Best to find something already built and done.
 
I think that project would have to be picked up at somewhere around 18K and all Air Frame construction sound with reasonable instrument panel for me to tackle that as a project. That will take some time. Otherwise just buy a flying project.
 
I think that project would have to be picked up at somewhere around 18K and all Air Frame construction sound with reasonable instrument panel for me to tackle that as a project. That will take some time. Otherwise just buy a flying project.
I think my offer would be less than that. They’d probably squeal like a stuck pig at that price.

I’d offer to give them back everything FWF if they wanted it. I couldn’t imagine trying to sell it. Put it up on EBAY?

I bought a previously flying, day VFR ONLY -7 project in April 24.

It has been my full time job since then getting it to the place where it is now ready to be reassembled as full IFR with glass cockpit.
 
I wouldn’t put an eggenfellner Subaru in a Subaru. Absolute junk. Price it for half of a slow build basic kit would cost and pray they don’t take you up on it. I have done planes like this in the past. You will be amazed at the an amount of rework required. Take out a bank loan and buy one flying with a lycoming and live happily ever after. If you just like to build things, like I do, then it can be a lot of fun to do. It won’t be cheaper and definitely not faster to the skies than just buying one.
 
All good advice. The Lycoming idea is fading. However, the post with an idea of replacing the Subie with a Rotax is interesting.

Thanks for all these thoughts.
 
All good advice. The Lycoming idea is fading. However, the post with an idea of replacing the Subie with a Rotax is interesting.

Thanks for all these thoughts.
Even if you’d want to do the Rotax swap. I’d still value the project at near giveaway price.

You are probably going to replace everything fwd of the firewall and probably the firewall too.

Never mind all the little rabbit holes, and all the man hours required to get everything plumbed correctly enough to consider things close to good enough.

Having taken on a previously flying project. I would strongly suggest you do a deep dive into investigating just how much $$$ you are going to spend on stuff. Do a spreadsheet and get real numbers.

It may be cheaper to buy an airworthy aircraft right now and save yourself a couple years of polishing a turd.

For me, I wouldn’t consider it unless it was damn near free
 
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Am aware of very nice 9a with Subaru. Am curious about conversion to Lycoming O-320.

Are there any sources of information about this process?

Key aspects to be aware of?

Major parts needed?

Approximate cost to accomplish a conversion?

Tips to minimize problems and maximize success?

Does this type of conversion make economic sense?

Thanks!!
Never buy an airplane with a power plant you don't want. The moment you do, you will stumble upon the most gorgeous airplane you ever saw with the exact engine you want. Every other aspect is cheaper to change than the power plant, especially, cross species.
The following is submitted for entertainment purposes only. My wife is loving her second Subaru in a row. Hopefully I offend everyone a bit, rather than a few a lot.
Top Ten things to do with a Subaru RV-9A

1: Put a cot in it and sell it to Kristi Noem
2: Replace the engine with a nice BBQ setup.
3: Drop it nose first from a tall crane and sell the carcass to a Hollywood aircraft wreck staging contractor.
4: Change the badging to Briggs and Stratton to boost the intrinsic value.
5: Take it out into the desert with some kindling and long sticks with marshmallows.
6: Donate it to a technical school for catastrophic destruction testing.
7: Take it to Appalachia with several cases of Mason jars and install a boiler, thumper, and coon pecker.
8: Find a restaurant or bar on Route 66 that needs an ornament for its roof.
9: Paint it like the Iranian Flag and take it to a local shooting range.
10: Two words. "Artificial" and "Reef"

Good luck. (Sincerely)
 
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Bought an unused Subie kit in storage for 20 years. Tore it down to the core block and modified it back to stock and am putting it in a Subaru STI car to replace a blown motor this week. See there is value in an old kit!

Note that when going through all the things Egg converted I would have never trusted it in a car for a cross country trip let alone in an airplane. Lot of failure modes in cooling and intake system especially where ports and connections were plugged or modified let alone the unique flywheel, reduction drive, cooling system and supercharger installation. Unless owner spend a lot of time making it more reliable, I'd always be looking for a vacant field within glide distance.

Got new oil cooler, radiators and super charger if anyone needs them. Pictures of car blown engine before and now engine built up with the Egg block follow:
 

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Interestingly, I am going the opposite direction with my RV3. I've taken off the agricultural O-320 and am installing a Subaru EJ257 STi. I've got half a dozen Subaru builds under my belt and just LOVE the one that I have on my Jodel (which isn't all that far from an RV-9 in its concept).

I've done one Eggenfellner on a plane for a friend, but was underwhelmed by the engineering of that one. I ended up doing a lot things differently on it to make it acceptable.

800 hours on my Jodel, with zero issues. Throw in fuel and fly, every time. Change oil and filter every 50 hours, spark plugs at 750, timing belt at 10 years. And that's all the work I have been needing to do on it.

In short - Not all Subaru builds are flying hand grenades. Consider flying it before pulling the engine....
 

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Interestingly, I am going the opposite direction with my RV3. I've taken off the agricultural O-320 and am installing a Subaru EJ257 STi. I've got half a dozen Subaru builds under my belt and just LOVE the one that I have on my Jodel (which isn't all that far from an RV-9 in its concept).

I've done one Eggenfellner on a plane for a friend, but was underwhelmed by the engineering of that one. I ended up doing a lot things differently on it to make it acceptable.

800 hours on my Jodel, with zero issues. Throw in fuel and fly, every time. Change oil and filter every 50 hours, spark plugs at 750, timing belt at 10 years. And that's all the work I have been needing to do on it.

Hans, I salute you for being a true powerplant experimenter, and for making it work. As a former Eggenfellner survivor owner, I'd love to hear more about your recipe for success in terms of engine mounting, propeller drive, fuel delivery, ECU, exhaust, cooling, and the myriad other problem areas I remember from my auto-engine experience!
 
Yes new engine mount, Cowl, Spinner, Prop.... People talk about ALL NEW... and cost. You can buy used, some times right off an RV when someone upgrades to a IO-360 or 390. Be creative. You are however better to buy an RV-9A with a Lyc already bolted on the nose. Unless that RV-9A is really cheap I would pass, unless you love the challenge. This is a major MOD so you will need to go through Phase 1 again, deal with FAA. Not a big deal, but there is a learning curve.

You are not the builder so you will need, buy the plane, take a LSI, Light Sport Inspector 2 day Class (which is also good for EAB's now). This will get you a "REPAIRMAN" certificate. That means you can work on that spacific aircraft, be it an LSA or EAB you OWN. You will get FAA involved with that as well.

If the Airworthiness Limitations does not have proper modern wording it has to be revised. So a revised Airworthiness will be applied for, It is a lot of paperwork but doable.

If you don't get your Repairman you can not do "Condition Inspections" or a Major Mod on this plane, like install a new engine and prop. You would need an A&P for Condition Inspections any way, regardless of this Major Mod. So getting the Repairman Certificate is a good thing. If you are not a super handyman and willing to rebuild it firewall forward don't buy it. The Subaru value used, I hesitate to venture a guess what is worth. Not a lot.
 
Yes new engine mount, Cowl, Spinner, Prop.... People talk about ALL NEW... and cost. You can buy used, some times right off an RV when someone upgrades to a IO-360 or 390. Be creative. You are however better to buy an RV-9A with a Lyc already bolted on the nose. Unless that RV-9A is really cheap I would pass, unless you love the challenge. This is a major MOD so you will need to go through Phase 1 again, deal with FAA. Not a big deal, but there is a learning curve.

You are not the builder so you will need, buy the plane, take a LSI, Light Sport Inspector 2 day Class (which is also good for EAB's now). This will get you a "REPAIRMAN" certificate. That means you can work on that spacific aircraft, be it an LSA or EAB you OWN. You will get FAA involved with that as well.

If the Airworthiness Limitations does not have proper modern wording it has to be revised. So a revised Airworthiness will be applied for, It is a lot of paperwork but doable.

If you don't get your Repairman you can not do "Condition Inspections" or a Major Mod on this plane, like install a new engine and prop. You would need an A&P for Condition Inspections any way, regardless of this Major Mod. So getting the Repairman Certificate is a good thing. If you are not a super handyman and willing to rebuild it firewall forward don't buy it. The Subaru value used, I hesitate to venture a guess what is worth. Not a lot.
ANYONE can perform maintenance and/or modifications on an E-AB! The only thing you can't do without the repairman certificate is the condition inspection.
 
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You are not the builder so you will need, buy the plane, take a LSI, Light Sport Inspector 2 day Class (which is also good for EAB's now). This will get you a "REPAIRMAN" certificate. That means you can work on that spacific aircraft, be it an LSA or EAB you OWN. You will get FAA involved with that as well.

If the Airworthiness Limitations does not have proper modern wording it has to be revised. So a revised Airworthiness will be applied for, It is a lot of paperwork but doable.

If you don't get your Repairman you can not do "Condition Inspections" or a Major Mod on this plane, like install a new engine and prop. You would need an A&P for Condition Inspections any way, regardless of this Major Mod. So getting the Repairman Certificate is a good thing. If you are not a super handyman and willing to rebuild it firewall forward don't buy it. The Subaru value used, I hesitate to venture a guess what is worth. Not a lot.
Umm, NO! This is NOT true! As Mel stated, Yes, without a Repairman Certificate for this airplane you cannot sign the airplane off as “safe for flight” after a Condition Inspection. However, you can do ALL work at any time on this airplane (or any EAB airplane), including all work during condition inspections, repairs, modifications, etc., not only can YOU do all that work but so can ANYONE!
 
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