Leroy Gardner

With a BUSA J3 Cub being modified into a super cub with a finished cockpit and 5 &1/2" tundra tires and all the scale features there is going to be some added weight, 17 to 18 lbs. is only a guess. This plane flies well with a G-26 and a DLE20 puts out the same power and spins the same prop. A step up to a 30 cc engine turning a 18"-6 or 8, ???? So what are you guys useing for this applacation. I hope to hold the prop to a scale size if possible, thats a 18" and a 6 pitch would help slow for landings.

I need to get an engine soon, the kit is due this week. I might add I'm not cutting up the cowl for muffler or carb so a side draft isn't going to work.

Thank you,

Leroy

Leroy Gardner

I just looked at the VVRC 21cc low profile engine, it's only 5" total height, 1450-9000 RPM, 2.6 HP @ 9000 RPM, props sizes are 16-8,17-6 and 17-8.

Any thoughts on this engine, anyone use it yet, your thoughts.

Leroy

speedracerntrixie

My Feedback: (29)

DLE 35RA. There is no such thing as too much power. The last 16lb airplane I had was powered with a DLE 55.

Truckracer

My Feedback: (19)

The DLE 30 and 35 are very popular here. The 35 is especially nice as it has the rear mounted muffler. I regularly fly a CUB with a Super Cub cowl with the 30 and a wrap around Pitts muffler. I built a new new SIG J-3 CUB (highly modified) last winter that has the 35. Everything fits in the cowl in either case. I use a 19-6 on the 30 and will probably use a 20-6 on the 35 though it hasn't flown yet. Yes I know those are larger than scale props but the engines love them and the 6" pitch gives good braking for landings. I don't like more than 6" pitch on this kind of plane in this size range.

The DLE 20, VV 20 / 21 would certainly fly the airplane and fly it well. 17-6 would probably be the preferred prop. I just prefer more power and the larger engines seem to aid balance.

Leroy Gardner

That thinking is along the lines I have. Sometimes finding the right power is a good thing with this plane, I go to scale meets where scale flying is judged and that will be how I fly it most of the time. Ballance is going to be an issue with a lighter engine and I would hate to add another pound in doing so and ending up wishing I went with a larger engine. I put a 35ccRA engine in my 1/4 Spacewalker and ballanced it with batteries, not sure if that can be done with the Cub because of the CG location and a full cockpit. Time will tell, hope others will share their experiences.

Leroy

Lifer

My Feedback: (1)

I have one of the H-9 Taylorcrafts with a DLE 30 and a 20x6 wood prop. Flies very well and the big prop looks great.

earlwb

Well, you do have a throttle on the engine. You do not need to use full throttle to fly the plane or even take off for that matter. So it is up to you.

coralcape

My Feedback: (4)

I have a clipped wing BUSA J3 with a ST 3250, Plenty of power and CG came out great. Good luck, red

ahicks

My Feedback: (2)

As much as I enjoy the 20cc engines, thinking if you want to stay with an 18x6 prop, I like the idea of a 26cc engine. I have an RCGF that runs great on that prop, but I sure wouldn't turn down the chance to add a G-26 to the stable.

Last big Cub I had ran a 2500 ST engine. That was a great combo!

cubcrasher

My Feedback: (6)

Hey Leroy,
I have both of Sigs big cubs. The long wing has a 90 four stroke and the clipped wing has a 180 four stroke. I have
been thinking about going gas. I like the looks of the Evolution gas engines because they look like they will fit in the
cowl without having to butcher it up. I'm going to the Hobby Shop this afternoon to pick up a case of glow fuel. I have
an extra cowl that I am going to take with me and see how the 20cc and 30cc fit. It's still gonna be hard to give up
that putt- putt sound of a four stroke.

Leroy Gardner

My cowl is in the making but won't have it for a couple of weeks, Fiberglass Specialties is doing it. If its as big as the one on my Spacewalker a 35ccRa will fit in there with no problem if there is enough length from the fire wall.. Other issues is moving the fire wall back pushes the fuel tank into the cockpit, may need to get creative there. Building scale has it's problems with short front ends and the Cub has one.

Throttle yes, you don't have to run it wide open, it's the length of the prop I would like to have, 17" is perfect for this plane, a 18" would be the max for what I'm doing, I will have the ground clearance. If I knew more about prop thrust on any given prop/engine combo it would help determine if it would move the weight of the plane I'm building and I know some of you have worked that out on a number of applacations.

An beautiful cowl should look like the one on my SW with a DLE 35RA between the dummy.

Leroy

Truckracer

My Feedback: (19)

The DLE30 / 35 is easy to hide in a CUB cowl. About the only problem is the sparkplug cap that has to stick out a bit. You could run a scale length prop with no problem though you might want to restrict the throttle travel on the top end so it doesn't over rev. For scale flight you would never miss the power anyway. I move the firewall back a bit from the stock location and slightly lower the thrust line (SIG) to a more scale location. I also add a bit of right thrust where the SIG CUB shows none on the plans. Not sure about the BUSA one. An added benefit of going gas is you can locate the tank anywhere which is always a problem in a CUB. The tank can also be much smaller than required with a glo engine as you use much less gas for an equivalent amount of flight time. While I suggested DLE, there are certainly other similar engines that would work just as well. I've just found DLE to be very reliable while still being economical.

captinjohn

Why give up that sound of sweet sounding 4 stroke engine? Convert one of the engines you have to spark ignition. They really start good with no kick-back & you can fine tune them easy to transition nice with a lot lower fuel consumption. Just mix your own fuel & save a lot. No nitro needed. Use Klotz oil & get your alky from a shop that has it. I can buy it here in Mich by any amount I want & it is about the same price as gas. To me there is not any 2 cycle engine that sounds right in a Cub.

Granpooba

My Feedback: (5)

Agree !! Good ole 4 stroke sound in a Cub can not be duplicated by any other engine.

cubcrasher

My Feedback: (6)

Good idea there Captin. I probably need to look at that. I'm like you. I don't care
for that two stroke sound in a cub.

av8tor1977

My Feedback: (6)

However, a gasoline engine does sound a lot better scale wise than a screaming glow engine....

AV8TOR

ahicks

My Feedback: (2)

I'd like to believe that, but I've been flying a little baby gasser lately. The 10cc Evo engine sounds just like a glow engine. During break in, it's suggested you run a 10x6 prop first. I skipped that step and went with an 11x6, and that thing is running at 13.5k rpm....

So maybe we could say the bigger gassers don't scream like a glow engine?

Truckracer

My Feedback: (19)

I agree with Captn' that converting a 4 stroke to ignition is a good idea. It really smoothes them out, makes them easier to start and even on glo fuel they use less of it than when on glo ignition.

But then ...... I don't really think a single cylinder, 4 stroke sounds any more like a Continental 65 than a gas 2 stroke engine. Neither is even close to the 4 cylinder, full scale sound. Really when flown at scale speeds a large 2 stroke gasser doesn't sound bad at all, at least to my old tired ears. With a large prop at fairly low RPM, they work for me.

2walla

My Feedback: (10)

Hate to bust your bubble.. I have basically what you are building. The fiberglass specialties cowl is crap for shape. Buy a cowl from horizon for the hangar nine super cub. It is the same as the dave patrick cowl. Then modify the front of the kit so that the cowl will fit. It looks so much nicer. For power i have an evolution 35 with a pitts muffler. Love it but it sticks out the bottom a ways . But does get good cooling. A valley view 40 twin will fit inside the hangar nine cowl and has plenty of power. Don't think it would fit in the fg specialties super cub cowl.

tsnaylor1964

Can' t have too much power. Flew my h-9 cub with an asp 160 four stroke twin for a year and it looked good, sounded good and flew scale like. Then the power demon bit me and I had to obey. Bolted on my Evolution 77 four stroke radial and it is even more fun. I still flies nice with the extra power but is four pounds heavier at over eighteen pounds so it is no 3-D airplane but is way cool to hear that radial engine rumble on by.
Tom

Granpooba

My Feedback: (5)

Hmmmmmmmmmmm ........... never seen a Cub looking like these ............ LOL

Lifer

My Feedback: (1)

The look does kinda grow on you! Has anyone ever done this on a full scale Cub?

ahicks

My Feedback: (2)

On the bold, couldn't possibly agree more....

av8tor1977

My Feedback: (6)

As a pilot of both full scale aircraft and models for more than 40 years, trust me when I say "There is no such thing as too much power in an airplane!" You can always pull the "loud lever" back, but when you want or need more power and it's not there, you're screwed! I've had some very, very uncomfortable moments flying both full scale airplanes and models when I did just that; needed more power and it wasn't there...... NOT fun.

AV8TOR

Granpooba

My Feedback: (5)

Being a retired ATP which equates to " Airline Transport Pilot ", I have to agree ! BUT !! In all of my real life aviation career, I have NEVER seen any Cubs that resemble these, or have radial engines.