How well sorted is the Turbo now?

[NWade]

Here is my very brief response to the original question, as someone who has an Aerovee Turbo that has not yet flown:

I believe that the changes and updates to the Aerovee Turbo mean that it is in a much better place now than it was under early iterations of the manual & kit. I believe that the liquid-cooling is the answer to the oil-coking/turbine-seizing problem (only time will tell for sure, but its a pretty good bet).

However, the Aerovee Turbo is still much more of a "project" than you might think. I say this as someone who used to work on race-cars. I hadn't built an engine solo before, but I'd helped out with rebuilds and was relatively familiar with all of the various parts on a basic Aerovee. I feel that while the engine build is not beyond the capabilities of the average Sonex builder, compared to building the airframe there are some "gotchas" and more learning that you have to do if you've never worked on engines before...
The project, first of all, contains many parts from third-party suppliers; and while Sonex is getting better about QC'ing those items recently, I had a few delays due to bad or questionable components; or because third party suppliers made changes to a part/product and never notified Sonex (and Sonex didn't notice it had changed).
Secondly, even though much of the engine is the same as an AeroVee (which is very simple, as engines go), the "fiddle factor" goes up quite a bit with the added intake fittings, oil lines, spin-on oil filter, exhaust wrap, air-balance line, MAP sensor & tubing, etc. On a B-Model Sonex this is probably not as annoying as my "A" model (with the tighter fit between the firewall and engine, and compressed space for all of the various FW-mounted items), but it is a noticeable increase in complexity - especially once you also add in the cooling system and its extra wires, water-hoses, pump, radiator, fan, etc.
And there are still a few "rough edges" that are left up to the builder. For example, the liquid cooling system comes with good instructions, but the chosen water pump (originally used with Toyota Pruises) has a specialty wiring connector that won't work with a standard 2-wire automotive plug. I have not been able to find the correct plug anywhere online or through local auto-parts stores (such as Napa; who are suggesting to me that Toyota considers that a specialty part and don't release info on it so they can require owners to buy parts from the dealership).
In the end, I do think the extra performance (especially at altitude and/or near gross weight) will make the turbo worthwhile. But adding up all of the ancillary costs and my time, I'm not sure I'd do it again - I've got a busy career and if I could get a pre-built 100 - 120hp engine for ~$20k, I'd consider the extra ~$5k - $6k worth saving the time and hassle, and getting my airplane flying sooner. A bad-luck combination of factors means that my first engine start was back in early January 2018, and I've been doing various ground-runs and tests off and on (with multi-week breaks, admittedly) for the entire year - working through oil pressure problems (too much; blew out the oil cooler), max-boost issues, minor aeroinjector issues, and now the fitting of the liquid cooling system. I gladly would trade some cash (or rather, a bit of a HELOC payment) in return for being able to fly the airplane! :-P
To repeat one more time: I have been surprised at the strength of the engine in my ground runs (even at only 38" of MAP) - and she appears to run like a top in these ~5 minute runs. So I anticipate having a lot of fun and believe that it is a good solution once you work all the kinks out. But as the sages of EAA will warn you: building an engine on top of building an airframe is basically doubling the scope of the project. If you enjoy the build and aren't in a rush to fly, it can wind up being a wonderful challenge and a satisfying thing to complete. But if you are eager to get in the air, then it may not be the right direction for you.

--Noel
Sonex #1339
Aerovee Turbo, Center-stick, Tailwheel, Flush (pulled) rivets, Aerobatic ailerons

[vigilant104]

killerfish,
The Sonex is a great plane. When you are done with your build, you'll have a responsive, fun, sturdy aircraft that you can use for light aerobatics, and you'll know exactly how it was put together.
I don't have any special insight regarding the turbo. As you point out, you've got time to see how things develop with that project, and there are other options available.

Mark

[killerfish72]

All,

Thanks so much for the great and thoughtful replies! I think a wait and see approach makes the most sense while I build. If I can find a better deal on the ULPower 260is or maybe even 350i(s); that very well may be the route and save some headaches. But they don't come cheap at $23-25K. Then, at that point, an RV-12is starts to look way more appealing and resale will eventually be something to consider. But I know I'd be missing out on aerobatics should I ever want to do them. Plus, the sonex is just flat out cooler looking in my opinion.

Thanks!
KF

[bvolcko38]

Regarding oil pressure, I too, blew out my oil cooler in the first 3 seconds of my first engine start up. My second engine startup blew out my oil filter gasket. Later, I found, with a mechanical gauge, I was getting close to 200 psi of oil pressure! I went to the hardware store and found a similar sized, but much weaker oil pressure relief spring for the rear plunger. I now have about 90 psi at cruise. Still a bit scary with a cold startup ..180 psi till the oil warms a little.

BV

[Gordon]

Sonex or an RV..........?

I have built and flew and sold 4 RV's since 1988. I have made money (20k or more on every one) and they all sold quickly, within weeks. If you want a Sonex to fly you can buy one for LESS than it costs to build it. If you are building a Sonex because you think it is the cheapest way to get a "flying Sonex" than you are building it for the wrong reason. It's cheaper just to go out and buy one.

Having said that........if you are building a Sonex because you WANT to "build it" and enjoy that experience than that is a legitimate reason to do it.

I moved away from the RV's this time and built a Onex knowing fair well that I would lose money on it when it comes time to sell it.......I didn't build it to make money....I built it because I love to build airplanes and this design (the Onex) intrigued me.....I now have 10 hours on it and it is a FUN airplane.....no regrets.

Gordon.....Onex....Hummel 2400...First flight June 17..2018

[Onex107]

Perhaps if you only built the $25K Sonex, as designed, your loss would be less?

[builderflyer]

Sonex vs RV-12...........?

The RV-12 will cost you more to build than the Sonex..........HOWEVER....the re-sale is so much higher with the RV-12 (or any RV for that matter) than the Sonex, that you would still come out ahead with the RV.

Something to consider.

Gordon...Onex....Hummel 2400.....(multiple RV builder/flyer)

Don't believe that this is necessarily the case..........there are many -12s (and other RV models) advertised for $15-20,000 less than the builder had into the project. That number could be quite comparable to what a Sonex builder will lose on his project.

Getting your money back on a homebuilt aircraft project is a fairly recent phenomenon which may be going away with the saturation of the market.

Just my opinion,

Art,,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,,,Jabiru 3300 #261

[killerfish72]

Having said that........if you are building a Sonex because you WANT to "build it" and enjoy that experience than that is a legitimate reason to do it.

That's exactly why I'd build one :) I have a plane already. Granted it's no rocket...It's a Cessna 152. But, it is one in immaculate condition, not ratted out at all. The idea behind a build would be that I think I'd really enjoy building an airplane and I think the Sonex is one cool airplane. I'm trying to see if I can somehow keep em both. If so, then, I'd go One-X with a normally aspirated Aerovee. If not, then, I'd be looking at a B-Model and take the aforementioned wait and see approach. I'd certainly love to build an RV-12is or even RV-7, but $80-100k budget to build just isn't happening.

[MichaelFarley56]

Regarding oil pressure, I too, blew out my oil cooler in the first 3 seconds of my first engine start up. My second engine startup blew out my oil filter gasket. Later, I found, with a mechanical gauge, I was getting close to 200 psi of oil pressure! I went to the hardware store and found a similar sized, but much weaker oil pressure relief spring for the rear plunger. I now have about 90 psi at cruise. Still a bit scary with a cold startup ..180 psi till the oil warms a little.

BV

Just my two cents Bill, but that's way too high on the oil pressure! Your engine shouldn't go over 100 psi even on a cold start, and most operators are happy if they see 40-60 psi in cruise. If I were to venture a guess, you may have a sticking oil plunger on your oil pressure regulator plunger (the one by the flywheel). You should be able to remove it and clean it up with an emery cloth until it moves freely in the oil passage. Totally up to you but I'd hate to see you crack a cooler or a line (it's happened to others before).

Good luck sir!

[Gordon]

Re-sale Onex....?

Off Topic....and my last comment about this....goes to "Onex107".....I DID build my Onex for less than 25k so my "loss" on the re-sale should be minimal. I paid $7075.00 for my Hummel engine, about 7k went into the "panel" and I bought an old (not started) kit #0024 for $6500.00 (fire sale price). Add in some incidentals and we came in under the 25k.

This is a fun airplane (10 hours flight time so far) and about as cheap as it gets.

Gordon....Onex 0024...Hummel 2400