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PDooley
05-06-2004, 11:44 AM
I’m at the point I need to select an engine for my WagAero Sport Trainer. Project. I would welcome any advice or opinions from other builders/flyers

My experimental has the wood wing/spar, jackscrew trim, pressure cowl, and electrical system and carries about 20 gallons in two wing tanks. No flaps. I intend to do recreational flying with the plane and anticipate that it will spend about half the time on pavement and the other half on grass/gravel/unimproved strips. I will fly it about 150 hours a year.

I tried to build the airplane as light as I could and anticipate it weighing in the high 700# low 800# range. I weigh 215# and am 6’3” and can only fly it comfortably from the back seat. 90% of the time I’ll be the only occupant.

I braced the fuselage to accept engines up to 125 HP, but could add bracing to get it to 150 HP per the Wag plans.

When I started this project, I came across a 100 HP Lycoming O-235 C with mid-time hours after one overhaul. I bought new mags, fabricated a crossover exhaust, new carb, alternator, Lycoming engine mount, baffling, etc. After fabricating the cowl, I took the engine out and thought I’d pull a jug and check out the cam. It was full of corrosion - cam, lifters, cylinders, rods – you name it and it showed pitting. I’ve basically got a junk engine with new accessories.

I’m looking for advice on what engine to select- experimental is OK and I’m not averse to building one. A factory new or outside rebuild would break the budget.

-O-200 Continental. Will it fit inside the cowl I fabed for the Lycoming?

-Another O-235 –but get the 115HP version. Can I use the same prop/accessores? Does a 115HP motor just spin faster than the 100HP motor?

-O-290 Lycoming- will the new Slick mags and the O-235’s MS carb fit this engine or would I have to sell them?

-O-320 I’d have to sand back my powdercoating, but I could add the bracing. Do I have enough fuel capacity?

Any experience, advice or opinions would be appreciated.

Phil

FlipFlop
05-06-2004, 11:51 AM
I?m at the point I need to select an engine for my WagAero Sport Trainer. Project. I would welcome any advice or opinions from other builders/flyers

My experimental has the wood wing/spar, jackscrew trim, pressure cowl, and electrical system and carries about 20 gallons in two wing tanks. No flaps. I intend to do recreational flying with the plane and anticipate that it will spend about half the time on pavement and the other half on grass/gravel/unimproved strips. I will fly it about 150 hours a year.

I tried to build the airplane as light as I could and anticipate it weighing in the high 700# low 800# range. I weigh 215# and am 6?3? and can only fly it comfortably from the back seat. 90% of the time I?ll be the only occupant.

I braced the fuselage to accept engines up to 125 HP, but could add bracing to get it to 150 HP per the Wag plans.

When I started this project, I came across a 100 HP Lycoming O-235 C with mid-time hours after one overhaul. I bought new mags, fabricated a crossover exhaust, new carb, alternator, Lycoming engine mount, baffling, etc. After fabricating the cowl, I took the engine out and thought I?d pull a jug and check out the cam. It was full of corrosion - cam, lifters, cylinders, rods ? you name it and it showed pitting. I?ve basically got a junk engine with new accessories.

I?m looking for advice on what engine to select- experimental is OK and I?m not averse to building one. A factory new or outside rebuild would break the budget.

-O-200 Continental. Will it fit inside the cowl I fabed for the Lycoming?

-Another O-235 ?but get the 115HP version. Can I use the same prop/accessores? Does a 115HP motor just spin faster than the 100HP motor?

-O-290 Lycoming- will the new Slick mags and the O-235?s MS carb fit this engine or would I have to sell them?

-O-320 I?d have to sand back my powdercoating, but I could add the bracing. Do I have enough fuel capacity?

Any experience, advice or opinions would be appreciated.

Phil

Phil...

Sounds like my Cuby is set up pretty similar to yours... I have a O-235-C1 (115 hp) and I'm very happy with the power and weight...

Steve Pierce
05-06-2004, 12:27 PM
Keep it simple. Flown Clippers for years with the O-235-C1. Only difference in it and the 100hp C is cam and carb jetting. I have a 2600 TT O-235-C1 that is disassembled and clean I would let go very reasonable. Cylinders would need OH. I removed because of excessive oil burn due to worn rings. I also have the part numbers for the automotive rings that fit the C1 and work well without paying the exuberant price of certified if you are experimental. I also know where there is an O320-D3G core first run out of a Beechcraft for $4500. The O-200 will fit with new baffles. I put an O-200 in a Pro-Tech that used to have an O-235 in it.

mvivion
05-06-2004, 12:30 PM
Phil,

I'd look for a good O-200 Continental, or if you can find one, an O240 Continental (125 hp).

My reasoning is that you will make nearly as much power, with substantially less weight than any of Lycomings. I am a fan of Lycoming, but the little Continentals are hard to beat, and have a lot of advantages over the little Lycomings.

The difference in the 115 hp Lyc 235 is that it was designed for the Cessna 152, and 100 LL gas. I doubt you'd even notice the difference between 108 and 115 hp in any case, with a light airplane.

The continentals are smaller than the Lycs, so it should fit in the cowl.

I think it'd be a big mistake to install a 150 Lycoming in this little airplane. It would be like putting a 150 in a J-3. This disturbs the balance and feel of the airplane, unless you do all the other mods, like big tail, etc, etc, in which case, you are building a "sorta" SUper Cub. Twenty gallons of fuel will not be nearly enough for a 150 hp engine, either.

I once owned a C-90 powered J-3, and it was a sweetheart. A near perfect combination of weight, balance and power. Plenty of power for those weights.

If you are really serious about thinking about more power, try to find an O240 Continental, or see if Superior is still selling conversion kits. I have to believe that a J-3 type airplane, powered by 125 hp out of a little Continental would have to outperform nearly anything on the planet, Super Cubs included, at least in the get up and go category.

MTV

FlipFlop
05-06-2004, 12:49 PM
The difference in the 115 hp Lyc 235 is that it was designed for the Cessna 152, and 100 LL gas.MTV

Model O-235-C1
Type 4HOA Direct Drive
Rating
Max. continuous hp., r.p.m.
Sea level pressure altitude 115-2800-S.L.
Takeoff (5 min.) hp., r.p.m. at full throttle 115-2800
Fuel (minimum grade aviation gasoline) 80/87

Bugs66
05-06-2004, 12:59 PM
Not sure what price range you are in but http://www.mattituck.com/ has the 0-200 and 0-240 experimentals. $15-17K with all accessories.

supercubc37
05-06-2004, 01:54 PM
You could also look into the Franklin 4A-235-B31 125 HP. Cost new would be less than an overhaul on either O-235 or O-200.

www.franklinengines.com

Matt

FlipFlop
05-06-2004, 01:56 PM
You could also look into the Franklin 4A-235-B31 125 HP. Cost new would be less than an overhaul on either O-235 or O-200.

www.franklinengines.com

Matt

Matt...

Unfortunately, the Franklin is 100 octane only...

supercubc37
05-06-2004, 02:09 PM
Not in an experimental it isn't. Burn whatever you want.

Matt

Bill Rusk
05-06-2004, 03:48 PM
Phil

I'd like to weigh in here a little if I may. I will probably take some hits but here goes.

Either go light... C-90 no electric... or... heavy... 0-320 w/full electrical. Anything in between is a poor compromise. The 0-235 and 0-290 weigh almost as much or more than the 0-320 yet don't give the Hp. ( 240, 264 and 244 pounds respectively, depending on model and whose book you read) If you are going to drag all that weight then get the Hp. Most folks are very comfortable hand propping a C-90 but an 0-320 makes a lot of folks nervous (not saying its right just saying what I've observed). So what happens is, as the engine gets over 0-200 size folks end up putting starters etc on the plane. An electrical system is going to add about 50 pds. Then you will want more fuel etc. Whatever you choose to do don't add a bunch of weight and then use a small motor.
If you do not want to hand prop, use the 0-320. If you are OK hand propping then I agree with Mike Vivian that the C-90 would be a great choice.

For all the others, I think the 0-235 and 0-290 are both fine engines and I have nothing against them, I just think the 0-320 is one of the best supported and generally one of the best aircraft engines out there. Why do the others when for the same or less money and weight you can get more Hp? Obviously this is an available CHOICE on an experimental that may not be available on a certified plane.

Just another opinion.

Bill

CptKelly
05-06-2004, 06:45 PM
The most horsepower you can afford is my advice. Go for a R-985 or Packard Merlin V-1650.

Mike

scott
05-06-2004, 11:41 PM
If you are really serious about thinking about more power, try to find an O240 Continental, or see if Superior is still selling conversion kits. I have to believe that a J-3 type airplane, powered by 125 hp out of a little Continental would have to outperform nearly anything on the planet, Super Cubs included, at least in the get up and go category.

MTV


Can a 0200 be converted to a 0240 or am I reading this wrong
Scott

mvivion
05-07-2004, 12:00 AM
Scott,

Someone else will have to answer that. I was told once that you could convert an O200 to a 240 by changing all the cylinders, pistons, etc, but I don't know for sure if that's really the case. I seem to recall seeing kits for that purpose for sale at one point.

My earlier comment re: the Lycoming 235 at 115 hp was that it was designed for the Cessna 152 for use with 100LL. The engine was approved for 80, but tolerated 100 LL better than the O-200.

I still think the 200 or 240 would be the hot ticket, even with a minimal electrical system.

If you install an O-320, you will be burning at least 8 or 9 gallons per hour of fuel. Put that in the context of your 20 gallon setup, and you've got an hour and a half to get somewhere and get on the ground. Not very practical.

Now, if you add a bunch more gas, of course, it gets heavier, added to the heavier engine, etc, etc, and you have a "light" airplane that ain't.

Probably the best performing Cub on the planet is run by a frequent contributor to this list. Jerry can tell you his solution in that little white airplane.

Mike

Steve Pierce
05-07-2004, 06:48 AM
O-235L2C (I think it is rated 125 hp) was in the C152. Was designed for 100LL and fouls plugs like crazy. O-235-C1 was in the PA16 and others. 108 hp or 115hp at 2700 rpm for take-off. They are very reliable with a2400 hr TBO.