180 hp engine/prop combinations

MontanaBird · Post by **MontanaBird** » Wed Jan 30, 2008 4:26 pm

I am considering 180 hp options to allow my '56 B Model MontanaBird to leap off the ground like a tiger, even in the summer.

Which fixed pitch props are STC'd for the non-fuel injected O-360 engine alternative?

I have discussed the variable pitch option with my mechanic/170 maintenance director, and he is strongly suggesting the fixed pitch option.

Thanks!

MontanaBird

Jr.CubBuilder · Post by **Jr.CubBuilder** » Wed Jan 30, 2008 4:41 pm

DelAir has some that are STC'd, check with them but I think the 76/56 is standard and I thought he had an 80" also.

I went with a constant speed, but if I were to do it again I would go with a fixed pitch as it will save you 20lbs plus the expense of acquiring and maintaining a prop and governor.

Post by **GAHorn** » Wed Jan 30, 2008 7:53 pm

Not to mention the recent spate of AD notes against the constant speed hubs.

Jr.CubBuilder · Post by **Jr.CubBuilder** » Wed Jan 30, 2008 9:05 pm

Fortunately mine is newer than those.

N171Q · Post by **N171Q** » Fri Feb 01, 2008 5:21 am

This is great. I've just been researching this myself.

First of all, MontanaBird, the fixed pitch options for the O-360 on your plane should be spelled out in your conversion STC paperwork. My Avcon STC says the biggest fixed pitch I can put on my plane (same engine) is the McCauley 76", which is what I'm running now. It's OK, but I am personally willing to give up some cruise speed for better take-off/climb performance.

I've been looking to go with a longer, flatter prop, but can't find any STC's or basis of approval to put, say, a 82/43 "Borer" or similar prop onto that engine. Obviously, the 80" seaplane prop is available for the O-300 equipped planes, and you can go up to 83" on the O-320's, but, unless I'm just looking in the wrong places, it doesn't appear possible to legally go bigger than the 76" fixed pitch on the O-360.

I've heard of some random field approvals for that combination, and I'm sure I've seen it before, but a supercub guy here in Anchorage that has pretty good knowledge on the issue said the O-360 is too rough of an engine for the longer props and the harmonics tend to cause them to throw tips after about 600hrs. Obviously very bad. But, just one perspective that I'd like to confirm.

OK. *deep breath* So, here's the question (which really echos the original post):

Is there any knowledge here of 80"+ fixed pitch props being swung by the O-360? And, if so, any RPM restrictions, problems, or impressions? And, finally, any basis for approval other than standard field approval with demonstrated ground clearance, etc.?

Of course Hartzell has the constant speed Top Prop 80" that has the dampner. I've heard great things about the performance, but it's 40lbs and $10,000 more than I care to think about right now.

hilltop170 · Post by **hilltop170** » Fri Feb 01, 2008 5:42 am

I personally know two guys who drilled out the bolt holes (illegal) on a Borer 82-44 prop designed for 150hp engines and installed them on stock 180hp O-360 Lycomings on their Super Cubs.

The first guy lost a tip years ago after about 500 hours but I don't know the details. After that he never flew a Borer prop over 500 hours and never had another failure. He flew his 180hp Cub about 300 hours per year. Unfortunately he didn't know the second guy.

The second guy called me to come pick him up one day. After about 500 hours, one prop tip broke off about 4" from the tip. Luckily, he was flying up the Knik River valley which is one huge gravel bar excellent for landing just about anywhere.

He was able to land without incident and used his cell phone to call for help. He told me until the prop actually quit turning it was shaking the plane so hard his eyes would not focus. He was still shaking when I got there with the spare prop.

Besides being illegal, Borer props are just too lightweight and not designed for 180hp. But, if you are willing to take the chance, nothing performs better. Just take them off and cut them in half at 500 hours.

N171Q · Post by **N171Q** » Fri Feb 01, 2008 7:33 am

OK Hilltop. pretty good confirmation on the Borer prop throwing tips. i can't imagine how dissapointing that would be... even over Knik. I was talking to Dan on Merrill Field and he said the same thing; that he had heard of guys flying them for 500hrs and then cutting them up. its no way to run a railroad.

I did just find out the Mccauley 1A200/FA8245 is approved for use on the O360 without RPM restrictions and is used in an STC by Crosswinds STOL on their 180hp cub conversions. While not a true "Borer", it is about what I'm looking for, and actually designed for this engine (read: no drilling required).

Anyone flown one of these 180 cub/cruisers with this combination? Should I just take out a second on the house and get the Top Prop?

53B · Post by **53B** » Fri Feb 01, 2008 1:21 pm

Our Super Cubs use that propeller with the 180 HP Penn-Yan STC. It kills the cruise speed (90 MPH @ 2500) but they have awesome climb ability and make fabulous tow planes. There are no RPM restrictions and I've never heard of any failures. I think the hub of this propeller is bigger than the Borer propellers. It was my understanding that the Borer propellers were for the 150 HP installations. The 1A200 is like the Borer propeller but for 180 HP installations.

ak2711c · Post by **ak2711c** » Mon Feb 04, 2008 8:42 am

Hi JR. Hey when I talked to you the other day about Bore Props for the 180hp on a Cub, I was refering to the 1A200/FA8245 that you mentioned. I should have clarified that. They have a great safety record. These are also sometimes refered to as club props because of how meaty they are. This is the prop I put on my Dad's cub and have been very happy with. We are getting about 105mph at 2450rpm with a 45 pitch. We just had it repitched to a 43 cause it was lugging the engine a little too much. I haven't had a chance to fly it since but my Dad said the cruise is still over 100mph. We used the Cub Crafter STC for it and it calls out a pitch range of 40-45. There are no rpm restrictions with it ether. Using the 150hp Bore prop on a 180hp engine is a death wish though. Also I think the weight you have for the 80" Hartzell is not correct unless you are refering to 40 lbs more than your old prop cause as I recall that prop with the dampener and spinner is a little over 70 lbs. Good luck JR.
Shawn

Jimmy M. · Post by **Jimmy M.** » Mon Feb 04, 2008 12:58 pm

We have several guys up here in northern Ontario with the 1A200 props
on 180 hp 172's on floats. They perform real well, seem to get around
100 mph, and get out of the water real quick, no one has ever had any problems to my knowledge.
I have one I plan on using on my project if I ever get it finished.
I was told these props were used on some ag planes with 0-540 engines (Pawnee?)

good luck

N171Q · Post by **N171Q** » Thu Feb 07, 2008 1:31 am

Thanks Shawn. The 40lbs I was referring to was how much more the Top Prop weighs over the fixed pitch I have now, including the governor, manifold press guage, and prop control cable. It all adds up...

Jim, my efforts to get the 1A200 field approved on my plane would be greatly assisted if I could show the FAA that the prop has already been demonstrated on the 172/O-360 airframe/engine combination. Do you or anyone else know where I can get a copy of the paperwork that was used to get this prop approved on those floatplanes you mentioned? Does Canada even use the same process as we do for this type of thing?

JR

Jimmy M. · Post by **Jimmy M.** » Mon Nov 23, 2009 3:17 pm

Sorry this took so long but I just came across the STC # you are looking for. You
probably have it already but here goes anyway.

SA181GL

canav8 · Post by **canav8** » Mon Nov 23, 2009 4:37 pm

Sorry I didnt look at the date of this thread but if this info helps, I will provide what I know. I have a 1966 Supercub with the 180HP, O-360-C4P conversion with the 1A200 FA8241 McCaully prop combination you are enquiring about. Cub Crafters STC#SA00562SE for the prop and STC#SA92NW for the engine conversion. The power is insane for the Super Cub. It gives me a climb rate of 1600-1800fpm in the winter and a 700-900fpm climb at gross weight around 4000ft density altitude in the summer.Take off rolls between 250-400 ft. I am seriouly considering putting an O-360 in the C170B. Still looking for the best set up. So far I have not found a good set up. I am also looking for the big Franklin setup out of Colorado.I thin kit is done by field approval. There is a significant appeal to power like this because of my density altitudes I deal with where I fly. The O-360 with a fixed pitch would make the C-170 an honest 4 place though. I will report what I find out since I didnt realize there were a number of you looking for alternatives. Lycoming is having a sale right now on reman Lyc 180's. Maybe a group buy would be a shot in the arm that they could use. V/R Doug

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