Movin up to 180 hp?

In your opinion who's got the best STC for going to 180hp in a Super Cub? There's CC and PENN YAN are there more? Do all STC's require a change to the fuel system?
toyin with the idea?
thanks jk

180

Penn Yan is half the cost and I believe better parts, Thats where Im going.

http://www.crosswindsstol.com/180h_p.htm

Another choice.

Ask Crash....

But the answer will be Penn Yan with Sutton/PPI exhaust or Atlee Dodge/Piper with enlarged tailpipe.

Penn Yann, dynafocal mount, TL mod, LEES. That is the most performance for your money. The X-wind is overpriced, but is a good conversion. Before the LEES was available the X-wind had the performance nod due to a better exhaust system.

What are the weight difference with the different conversions? I ended up going with the cubcrafters,but that was several years ago and it was cheap by todays prices.At the time they were claiming the other kits added lots more weight up front.I dont know this to be true,just beleived the sales pitch at the time.They claimed dynofocal was heavier .Seems like most people very happy with dynofocal kit though.Penn yan even claims they reccomend conicl mount if given choice,lighter and less expensive.At the time i ultimtely chose cubcrafters becuase they had engines ready for shipment and at the time they were about the same price.Who kows? The only drawback is i have the solid crank which is good for having no rpm restrictions,but cant ever install cs prop.I guess i wonder why penn yan and cubcrafters both reccomend conical mount .Penn yan has this in bold black letters on their site.It basically state they provide the other option in case you have a dynofocal engine in the barn

The choice between Cub Crafters and Penn Yan comes down to cost (Cub Crafters was around $7,000.00 more) and straight versus dynafocal mount. I talked with the Penn Yan conversions specialist two weeks ago and he said 99% of the kits they sell go out with a dynafocal mount (Airframes Inc. builds it for them).

For me it was not so much the cost as it is the well known fact that an O-360 shakes more then an O-320. Bolting an O-360 up tight (conical mount) to a light airframe like a PA-18 did not seem like a smart thing to do. My IA owned two 180 hp Cubs a few years back. One had a conical mount, one had a dynafocal mount. He said the one with a conical mount shook so bad that upon removing the wing inspection covers you would get a hand full of "rib to spar" attachment screws. They balanced the prop several times and even tore the engine back down to re-weigh and balance everything. No dice, finally he sold the shaking piece of crap.

Charlie Center of Crosswinds STOL had similar advice, he uses 100% dynafocal mounts.

Of the three O-360 kits availible, (Penn Yan, Crosswinds STOL, Cub Crafters) only one, Cub Crafters, uses 100% conical mounts. I also dislike Cub Crafter's cowling with all the little twist fasteners. Piper PA-18 cowl latches are one of the best things about a Super Cub. Take care. Crash

P.S. The Dynafocal mount weighs about 3 lbs more then a conical with all the hardware.

In my limited time and experience with Super Cubs I have flown 2 different 180hp conical mount with 90" props. I did not think anything about vibs, one had been dynamic balanced and the other had not. I Did notice small difference there. Loni has flown the one SuperCub I am talking about and said he could not wait to get back in his 160 hp because he did not like the vibs. So for guys use to 0-320 there might be some merit to dynofocal.

I myself would take the vibs for conical mount because it is cheaper to replace those little guys (rubber). I also would be interested in the weight savings, which I thought was more then 3 lbs. (I might be wrong there) but 3 lbs is still enough to make the difference for me.

Greg

I do get some extra vibration,but not excessive enough to concern me.I wonder if i am just lucky with the engine i got. All the cub pilots that have flown it or rode with me really like the way my old junk flys and never even noticed a difference in the vibration over the 150 hp.The only time i feel excess vibration is when i accelerate quickly.I guess if it vibrated that bad,i would definitely change to a dynofocal.Penn yan claims a 7 lb difference in the weight.The 7lbs is negligible except it is so forward of the center of gravity.Way out front may make it feel much more heavy.Isnt the dynofocal mount shorter than a conical? If it is,it may feel lighter than a conical cause the weight is close to center of gravity.

I think the total weight difference between a conical and a dyna focal is 11 lbs. This is taking into consideration the larger Lord mounts and the dyna focal ring and the cases.Kevin

180

While looking at different conversions for the 180 into a PA-18 I stopped by CubCrafters. At that time I was shown the fiberglass coweling, a two piece system designed so it can come off without removing the prop, seemed like a good idea. also heard it was very difficult to fit on the cubs, seemed to take alot of effort to make it fit right. Earl Barnes gave me the tour and was very helpful. To get the STC paper work, I have to buy the whole kit, rear mounted oil cooler, coweling and alot of other parts come with it. The cost was close to $8000. Earl told me they were working on a new coweling made of kevlar or carbon fiber, lighter and probably stronger. Penn Yan has the same kit for the conversion with STC paper work, oil cooler ect. for aprox $4000. I believe that the coweling from what I have seen is very good quality, I don't know how well it fits up, but expect it would not be a problem.
My plane will have the Dynafocal mount, its stronger and would help the 180 vibration and torque issues. While visiting Mark Englerth at Big Lake Alaska, who sells the "THRUST LINE' engine mounts, he did mention that several conical engine mounts were found to be cracked or broken on inspection. Well thats my 2 cents worth

I owned a CC 180HP Supercub. The vibration in the cockpit was very similar to a 160hp Supercub owned prior. One interesting thing I noticed about the CC cub one day. My son was going to fly it. I followed him to the runway on my bicycle to watch some T&G's. During the runup and mag check, the rear tail feathers were shaking back and forth, almost violently. The thought that occurred to me then was the tail cannot take that for very long. It seemed all the vibration from the 180 ended up in the tail. It was shortly after that I checked into why the conical mount was used instead of dynafocal and was told it was for weight savings.

I also watched my son fly our 160 hp and do the runup/mag check and did not see anything near the tail vibration.

Definitely go for the dynafocal.

Scott

The tail vibration is from the added thrust not the engine mount. I went with the conical due to weight savings and the ability to use the same engine mount as the 150. The motor mounts are harder to change in the dynafocal and they cost more. The dynafocal mount is bigger and takes up more room between the firewall and the engine. I don't really care what you do, just my thoughts. I am experimental, if I was certified I would use the old Jensen STC, it is easy to install and you can use your old cowling, and motor mount. All you have to modify is a fuel line and widen your baffle. Low cost and very easy to installation.

for what its worth flying at 40 mph at 2500 rpms for up to 6 hours at a time i am glad i have a dynafocal mount
johnson came up with the mount do to towing gliders they would crack the straight mounts then it wented to pete jenson and he sold it to Penn Yan and most of the other stc went to airframe inc
i don't about the straight mount on the dynafocal mount the base of the oil screen housing is 5" off the fire wall empty weight 1165 CG 13.33 thats with 3 radios GPS ext baggage metal head linder under seat storage panwee 82"prop 850s with cessna 185 rims and brakes on heavy 1 1/2 gear with long step long wings with tips and a 3 tow hook release system

in all it is one heavy cub gear

I didn't really know before I made the conversion where my EWCG would end up. The stock Piper O-320 set up was at 11.06 EWCG. After the Penn Yan O-360 conversion it came in at 11.00. It lands great and every thing using power it does better. I now regularly climb up to 10 to 14,000' to take advantage of "winds aloft" and get out of smoke. The O-360 gets you there without even breathing hard.

I was showing 137 mph on my gps at 12,000' while my buddy at 2,000 was doing 85. Crash

Crash,
14,000 feet, does your cub have oxygen?

The choice between breathing smoke or thin air, I'll take thin air for a time. Normally I fly pretty low but with all the forest fires we've had the last two years, sometimes climbing on top has been the best option. Crash

For what its worth, I've got about 225 hours on my SC after the rebuild with the Penn Yan 180hp conversion using the conical mount and vibration is not an issue. I heard all the horror stories during the rebuild but none of it has come true. In my opinion there is no need for concern if you use the Penn Yan conversion with a conical mount.

I have a CC180 and do not see any difference in vibration from the 160hp. The cowling fits perfect and goes back on like butter. I also like the fact that it retains the swing out feature, to me thats a big plus.

Well guys alot of good info here, thanks. I had not heard of the "old Jensen STC" thanks ksecub, will look into that. Crash, your ride sounds preety good and your happy with the outcome. Would you do it the same again, what would you change? I'm with ya on the smoke, jeez it really sucks. Even up on the slope, sheep hunting last year! Gunny sounds like your ride is real nice one as well.
Thanks to all who posted with there experience's I'll be following up with some pm's.
Now where did I bury that bag o' money. This site rocks.
jk

As far as the mount decision, the question you have to ask yourself is "How much do I understand and believe in the concept of fatigue failure?'
For the exhaust, the question is "How much do I understand and believe in the concept of a tuned exhaust?"

delete

Pure BS Diggler

ksecub, How do we find the Jensen guy?

delete

[delete

Copy that diggler, thank you.

This is an interesting thread. I have some experience and a question.

I have a Cub Crafters converted PA-18 to O-360 C4P. The plane is straight, low time, the prop is a balanced 1A200 82" McCauley. I don't have a lot of experience to compare with. With that said - The plane is extremely smooth in flight. I learned from observers that the tail shakes bad when doing a static run-up. So I intend to get the Crosswinds Tail beef-up mod. I think all the PA-18's converted to 180 hp should get that mod - function of prop wash. Note - my McCauley climp prop (82" 1A200) is much bigger than the Borer for the O-320's. If you haven't seen the two side-by-side, you will be amazed. The O-320 Borer really looks like a small prop to me now. I really like the CC cowling. Just did an annual with lots of engine tweaks and the prop stayed on the whole time. I think the CC cowling looks really nice and functions well. I don't like the Scout type of cowlings. The CC cowling still stays with the PA-18 styling. The oil cooler cracked the baffling to which it was attached and it has since been reinforced. Just make sure that thing is not simply attached to the baffling. It's too heavy for it. I bought Cunningham covers and Lynn already had the measurements for the CC planes. So, getting a nicely fitting cover for my plane's cowling was easy. I've got an ace mechanic who really cares about his work (as opposed to factory line work - more production oriented) and he found quite a few things that were small, but unprofessional (i.e. scat hose free to rub on fuel line). We fixed them all, but beware. The conversion requires the both fuel selector. I like that mod anyway, but you are forced into it with the CC conversion (the others require it I think too).

So anyway, I have a question too. What is a conical and what is a dynafocal mount? I have heard the terms and I know mine is conical. But what is the difference? How does one do a better job at reducing vibration, etc?

180 hp tail shaking

Hi all;
Just out of curiosity....are there any instances of structural failure in the stabilizer or elevator directly attributed to having an 180 hp engine on a Supercub?
It looks like Crosswinds has a great fix for it if it is a problem, however it looks like it might be a major deal to install it?
The PA-25 Pawnee has up to 260 hp...but they have twice the flying wires and a non-adjustable stabilizer, so maybe Piper had to go that route with the added stress?
Thanks...
Randy

The Crosswinds tail mod doesn't look too bad to install. But the $1600 or so price tag has kept it off of my plane for now. It sounds like the mod is more to keep things like the jack screw and bushings from wearing out from excessive vibrations. I don't think there is a fear out there that the tail will fall off with the 180 hp conversion/no Crosswinds mod. By the way, the tail shaking only takes place at static and initial ground roll. The tail feathers are smooth as can be at cruise.