Alternative Engine Selection (warning long post)

[infra_red_john]

Hello all,

 

Warning : long post !

 

I am a newbie in the aviation world. I don't claim to have knowledge on anything. Just searching and learning. I dream that one day i will fly my OpenEz.

 

I have been investigating my engine options and narrowed down my choices to the following :

 

Rotax 914

 

Pros :

Light

Supercharged

Certification (not that i would get the certified model)

Not bad price

 

Cons:

Weak (115HP) (also low diplacement -> low torque)

Not cheap either (with the same money more powerful alternatives exist)

Never installed in an OpenEZ (or LongEz) as far as i know

 

Subaru EJ25 conversion

 

Pros :

Power! (160HP - 200HP depending who you ask, stock is 168HP)

Cheap (found one for 900 US$ in almost new condition)

Has been used before

Redundant ECU for ignition and EFI available

Reliability more or less proven

 

Cons:

single spark plug, single injector per cylinder

time to implement & trouble shoot unknown but probably long

not exactly lightweight ... (compared to the standard O-235)

 

Subaru EG33 conversion

 

Pros :

Power !!!!!! (250-300HP easy, stock is 256HP)

Cheap (found one for 650 US$ in rebuildable condition)

Has been used before

Reliability more or less proven

 

Cons:

single spark plug, single injector per cylinder

Dangerously powerful for the OpenEz ...

time to implement & trouble shoot unknown but probably long

not exactly lightweight ... (compared to the standard O-235 or O-320)

 

 

MAZDA Renesis Conversion

 

Pros :

Power ! (190HP - 220 HP stock is 192HP for the four port, consensus is 200HP easy)

Cheap (found one for 1500 US$ in good working condition)

Has been used before

Reliability more or less proven

two sparks, two injectors per rotor

Redundant ECU for ignition and EFI available

 

Cons:

time to implement & trouble shoot unknown but probably long

not exactly lightweight ... (compared to the standard O-235)

 

HONDA F22B DOHC / H23A

 

Pros:

Power ! (150HP - stock 150HP not easy to go for more without extensive modification)

Cheap (found one for 400 US$ in working condition)

Superior Honda Engineering

Relatively low cosumption

Closed deck block (Very stong, only valid for F22B though)

 

Cons:

Never used before

Unproven (although cam100 & cam125 have good name but not the same engine)

time to implement & trouble shoot unknown but probably long

not exactly lightweight ... (compared to the standard O-235)

 

HONDA H22A VTEC

 

Pros:

Power ! (180HP - stock is 200HP but at 6800 RPM. 180HP is possible at lower and safer RPM)

Cheap (found one for 1000 US$ in good working condition)

Superior Honda Engineering

Relatively low cosumption for the output

VTEC (more torque and HP at lower rpm band, i wouldn't be surprised if it would cruise more economically than all the others)

 

Cons:

Never used before

Unproven (although cam100 & cam125 have good name but not the same engine)

time to implement & trouble shoot unknown but probably long

not exactly lightweight ... (compared to the standard O-235)

 

Estimated installed prices +/-:

 

Rotax 914: 13000 Euro / 19500 US$ (Quote from local dealer for all i need)

Subaru EJ25 : 7000 Euro / 10500 US$ (engine, rebuild service, mount, reduction gear, ECU)

Subaru EG33 : 9000 Euro / 13500 US$(engine, rebuild service, mount, reduction gear, ECU)

MAZDA Renesis : 8000 Euro / 12000 US$(engine, rebuild service, seals, mount, reduction gear, ECU)

HONDA F22B / H23A : 7500 Euro / 11250 US$(engine, rebuild service, mount, reduction gear, ECU)

HONDA H22A VTEC : 7500 Euro / 11250 US$(engine, rebuild service, mount, reduction gear, ECU)

 

Lycomings are not present in my options because a rebuilt IO-320 engine in my country (Greece) was quoted to me at 20000 Euro (30000 US$ !!!) by local distributor, which is out of my reach.

 

Easiest to install and lightest is the Rotax but it is expensive compared to the others. Also most runways are short (1500ft +/-) here and the relatively low HP could cause trouble.

EJ25 is a good compromise but i am a bit skeptical as far as the weight is concerned. (anyone know what is the installed weight for this ?)

EG33 is more or less out of the question . The HP is dangerous. Only included because it is cheap. Won't use it ...

Renesis is good but heavy. Cast iron parts raise the weight. (maybe i should wait for the all aluminum 16x ...) Also the consumption is high compared to the others (epecialy the Hondas)

The Hondas are interesting with lower weight than the others and very good power / consumption ratio But they are a venture into the unknown . Will they fit ? Are there reliable ECUs ? A lot of unknowns here. On the other hand the experiment has its joys ...

 

My aim is the following :

 

175 Kts Cruise at 9000ft +/- with the lowest possible fuel consumption and

the lowest empty weight possible.

I think that the cruising speed can be attained by all these engines. the weight might prove problematic though.

 

Country limit for 2 seat homebuilds 550kg = 1212lbs gross, so i theoretically aim at weight of 363kgs = 880lbs without pilot passenger and fuel (is that doable ? i know original LongEz was 760 lbs +/-).

 

Any thoughts / advice on these ? Something i missed ? Does anyone have installed weight or long block weight data on these ? (Apart from Rotax,

i get conflicting numbers from the web ...) What would you choose ? Why ?

[Kent Ashton]

Auto engines aren't as cheap as you may think. There's only a modest saving until the time comes to rebuild the engine (after 10 to 20 years of flying)--then the rebuild is cheaper. Check out the Eggenfellner Suby engines. They are beautiful but just as costly as a Lycoming.

 

http://www.eggenfellneraircraft.com/

 

If you like the idea of an auto engine conversion, go for it and good luck to you but you can buy a used Lycoming and rebuild it for about the same money.

-Kent

[raiki]

Don't forget the Jabiru engines. The 3300 (120hp) would make a clean, economical EZ. The 5100 (170/180hp) would be fast, and the engine isn't overly heavy. www.jabiru.net.au

 

These are very narrow engines (compared to the Lyc.) so I think a much better cowling could result in a moderate speed increase.

 

They are also true aircraft engines, not auto conversions, and made almost entirely from billet alloy on CNC machines. Very few cast parts. Very nice looking engines. Also have dual ignitions and dual carbs (altitude compensating, no mixture control).

 

At the moment I am considering the 5100 for my Cozy but I think I'd really like fuel injection (based on my 172R and SP experience). Heaps of time until that descision needs to be made.

 

I initially trained in a Jabiru aircraft with the 2200 4 cyl engine. I have about 70 hours in that, long before I started flying GA, and never experienced engine trouble. The 3300 is basically the same engine as the 2200 but with 6 cylinders instead of 4.

 

If I was to build an OpenEZ I am pretty sure I would use the 3300. Ecomony and reliability. I think about 23L/hr ( about 6 gal.hr). Endurance would be pretty good. Also because it is a 6 would/should be smooter than a 4. It's an Australian built engine so I am probably a little biased.

[RGlos]

Don't forget used but in good condition. A mid time Lycoming is going to be lower than any of the prices you have listed.

 

With 1000 to go before rebuild you have a long long long time to enjoy.

 

Consider this. if you got the chance to fly one hour each day, every day for a full year, you would only used 365 of those hours.

 

Most of us started with used engines. There are some exceptions of course but a lot of us are just like you, on a budget of sorts.

[argoldman]

OOOOOH,

 

Would that the cost of an engine is restricted to it's purchase price.

 

If you are lucky and fly the engine a lot, it may reach its TBO, typically, you must, at some time replace the expendable cylinders and many times many of the other things that you already bought. Although these engines (aircraft) are reasonably good, they are running at the limits of their structure (many times) and must be constantly maintained. Cylinders, pistons, et al, are, in these beasts, considered expendable.or sometimes repairable and then expendable.

 

How many times has Lycoming changed the gears on it's oil pump. How many crankshafts have been replaced?

[infra_red_john]

Thank you all for the input.

 

raiki :

 

The Jabiru 3300 is Very attractive indeed. It is certified, can use mogas, and is really light. A negative is the price though: Quoted in Greece by local distributor, it is approximately 15000 Euro. That is 22500 US $. As much as used and heavily abused lycomings here... If nothing else presents itself i will give that a good consideration.

 

kent ashton, RGlos :

 

Your points are certainly valid for the US. If i lived there i would have no hesitation to get a good mid time Lyc. Here things are different. GA is considered the rich man's sport. With less than 30 GA aircraft sold each year, most of which are used imports any way, the market is small and the prices high. Used engines are not sold in reasonable prices. It is very difficult to locate a usable 2nd hand engine that costs less than 15K Euro. 20000 euro is what i got for a rebuild lycoming. That is 30000 US $ !!! It is too much. Compare that to the average yearly income here that is 9000 euro !

That is the motivation behind the alternative engine search.

Right now, a used subaru EJ25D with all accessories sells for 1200Euro shipped to my back yard. Supposedly it needs a rebuild, that is another 1500 Euro (and the engine is practically new). An EC3 EFI & Ignition Controller from rotaryaviation.com is more or less 1000US $. An RD-1B reduction drive from the same people is 3500 US $. 4500 US$ for both, that would be 3000 Euro.

Grand total less than 6000 Euro and i will add another thousand for misc other items. 7000 Euro for a quality rebuild engine, one third of the equivalent Lycoming in the local market. Do i forget anything else that should be added ?

As far as reliability is concerned i am convinced that both the subaru and the honda engines are virtually indestructible. I have seen with my own eyes 280HP - 330HP EJ20 turbo charged engines with 120K+ kilometers (70K+ miles) with little to no measurable wear (with careful users though).

 

 

Of course importing a used lyc is an option but i am not really certain that the local authorized service centers (there are two or three here) would accept servicing something they haven't sold themselves ... (i am searching that option too though)

[gilbertexp]

[As far as reliability is concerned i am convinced that both the subaru and the honda engines are virtually indestructible. I have seen with my own eyes 280HP - 330HP EJ20 turbo charged engines with 120K+ kilometers (70K+ miles) with little to no measurable wear (with careful users though).]

 

Agreed that they will run forever in an automotive application; what concerns me is the reliability when running them at the high rpm settings when applied to an aircraft.

 

John

LongEZ O320

Phoenix, AZ