Any current generation subaru FWF's out there

[shogan50]

I'm curious about the current/next generation of Subaru powered aircraft. Not having followed it for a while, it would appear that several Egg... purchasers finally gave up after spending a fortune and got a Lycoming, suffering from reliability and under performance. A few appear to have prevailed after removing a lot of the egg stuff and turbo charging and now play in the same league as Lycoming as far as power and fuel efficiency. One or two, especially 9's, still run original Egg's, . And finally there is Ross, who built his own FFW and at least until his engine got tired was in the same league if slightly lagging (your honest account much appreciated). Are there any current builders looking at Subaru's more or less from scratch?

I know the whole capital E 'Experimental' vs. the plug and play Lycoming argument and don't want to debate that. Just curios if any current builders are planning to go that way. If there are any at KPAE, I'd particularly love to see.

I never did hear what happened to Eggenfelner. It would appear that he closed is doors about 4 years ago, leaving some builders quite unhappy.

[txaviator]

Originally Posted by shogan50

I never did hear what happened to Eggenfelner. It would appear that he closed is doors about 4 years ago, leaving some builders quite unhappy.

He's at Viking Aircraft Engines, the Honda engine alternative.

[SvingenB]

Originally Posted by txaviator

He's at Viking Aircraft Engines, the Honda engine alternative.

And doing pritty good by the looks of it. The main difference is the Honda engine is fit for the job, a different legue compared with the Subaru.

[RV10inOz]

I only know of one successful Subaru install in all of Australia, with lts of doing it right engineering, getting cooling right etc. more HP than most but probably not claimed HP. Pretty quick, but slower than a 180 Lycoming.

Fuel burn is worse. And this guy has all the gear to know what the injectors are squirting.

Fair to say, he would not do it again even if it were free, and he is preparing a FWF for a Lycoming, so here is a good example. The rest not so much.

[RV10inOz]

Originally Posted by SvingenB

And doing pritty good by the looks of it. The main difference is the Honda engine is fit for the job, a different legue compared with the Subaru.

Are there any gear boxes involved from this mob?

If so

[SvingenB]

Originally Posted by RV10inOz

Are there any gear boxes involved from this mob?

If so

Here: http://www.vikingaircraftengines.com.../Pictures.html

[rv6ejguy]

The Subaru engines are just as capable as any Honda engine and FAR more flight proven with something like a half million flight hours to date. There are hundreds of them flying (over 600 delivered) in RAF 2000 gyros and quite a number have over 1000 hours on them now.

The turbocharged STi engines appear to be the way to go for the typical RV3-8. Weight is only slightly higher if done right using the MT composite props, performance is well above the Lycomings and fuel burn is fairly similar. One is currently flying here trouble free and Randy Crothers is about to have his flying again soon after trying the atmo route for a couple years and finding performance lacking. He will have a new STi bottom end with SOHC heads and a new Aerocharger turbo.

Russell Sherwood flies an atmo EG33 powered Glasair in the SARL races and waxed all comers in his class and won it in 2011 I believe. He has been flying for years and has over 450 hours on his.

Keith Spruerer has been flying an atmo EG33 for years in his Cozy, has about 800 hours I believe on it now.

My friend Bill Baxter has about 300 trouble free hours on his EJ22 turbo powered Glastar. Gives really good performance.

Many Egg users have removed their engines and fitted Lycomings after various problems with the EZ30 engines and GEN 3 gearboxes. Others are staying with them through the closed support group Subenews which is of exceptional help technically, dealing with fixes to problems and even working on new gearbox parts and fixes.

Many other Egg users have experienced few if any problems and are happily flying with several hundred hours on them now.

My own plane is all apart now after 9 years and almost 360 hours. I'm making big systems and cooling setup changes and freshening the tired engine. I'll be posting photos and what I have found on a new web page if I ever find the time.

What do we know so far? Seems like universally, these engines don't enjoy a diet of 100LL as it often leads to valve issues. Operated on unleaded mostly, we see excellent life for the most part, many of the gyro engines are going 1500-2000 hours before overhaul and the high time one was over 3800!

Gearboxes and TV are still issues although we have seen reliable results using both the Marcotte and Autoflight PSRUs. I'll be experimenting with flywheel inertia changes on mine when it goes back together. Some Egg Gen 3 gearboxes are working fine, others have suffered multiple problems with bearings, shaft fractures, seal problems and weld breakages. Fixes are in the works for these through the group. One Geared 200Z Sube box suffered an early gear failure which puts into question the reliability of that choice which was an alternative to the Gen 3 boxes (bolt on, no thrustline change). The Ross gearboxes have always had problems but some people know and check them often and they work for them. The GAP boxes have not proven reliable behind the six cylinder engines as Russell discovered- he now uses a Marcotte M300 with no issues.

Done correctly, the Subaru can give good and reliable service as many have proven. Done poorly and you are in for a world of misery and headaches. As I have advised for many years now, Subarus are probably not a good choice for non-gearheads and non-engineers and your average RV builder as there are no fully engineered and tested packages available. Most RV builders are best served by fitting a Lycoming or clone IMO.

[SvingenB]

The Honda engine is designed to run continuously at WOT for prolonged time as a an outboard engine for boats. For aero conversion the Honda is perfect. The Subaru is designed for auto use only.

It is therefore much easier to get it right with the Honda than with the Subaru. I'm not saying that Eggenfellner has everything right with his Honda conversion or that using a Subaru is wrong, but I think there is less likelihood of getting it wrong with the Honda because it is initially designed and tested by Honda engineers for a similar purpose. The Honda is also less HP and that simplifies.

Regarding PSRU, the recipe for endless problem free run is found on the Rotax 912. It's called a clutch. Eggenfelner's PSRU looks a bit strange, nothing to save those cogwheels from beating during start and stop and low load running but I guess if enough steel is used, it will hold together for a light prop.

[shogan50]

Thanks for the info Ross. I suffer being a former gearhead and current engineer.
I know enough to be dangerous in fluid dynamics and cooling drag and would like to try some things on a sub, but the two obstacles for me are the lead issue and uncertainty doing aerobatics with a turbo. KPEA doesn't, to my knowledge, offer mogas.

[shogan50]

Originally Posted by SvingenB

The Honda engine is designed to run continuously at WOT for prolonged time as a an outboard engine for boats. For aero conversion the Honda is perfect. The Subaru is designed for auto use only.

It is therefore much easier to get it right with the Honda than with the Subaru. I'm not saying that Eggenfellner has everything right with his Honda conversion or that using a Subaru is wrong, but I think there is less likelihood of getting it wrong with the Honda because it is initially designed and tested by Honda engineers for a similar purpose. The Honda is also less HP and that simplifies.

Perhaps, but there seems to be preponderance of evidence that subaru's hold up just fine, as Ross and others report. I'm not sure I've heard of any core failures - lots of fuel or electron starvation, or gearbox/prop failures.