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P-Ponk ?????

WSH

Registered User
What can anyone tell me about P-Ponk engine conversions?
I'm in need of a go fast(er) XC rig and I'm considering a 180 that has the 0-470-50 conversion, and nobody around here (mid-atlantic) seems to know anything about it. Good, Bad, Indifferent?????

Thanks

WSH
 
P-Ponk

Get ahold of ABCACY when he's on or send him a PM, he just did his 180 this year and loves it! B&J in Palmer, Alaska did the work for him.
 
The ponk engine is rated at 235 horses instead of 230 on the original. That said it definitely brings the 180 up closer to the 185 than any other mod for the price.

They also claim a 2000 hr TBO even though the parts they use come off of engines with a 1600 hr TBO. They claim it is their engine and they can call it what they want.

If they go out of business there is no inexpensive way to convert it back. The case is shot.

That said I have been maintaining a couple for about 1500 hrs each and see no major problems with case cracking or fatigue that should keep it from making 1600 to 1800 for TBO. I still don't see the 2000 mostly due to the cylinders and timing as to feasibility to repairs that close to overhaul.

All in all a good engine.
 
Call Alaska Seaplanes in Juneau, (907) 789-3331 and talk to Craig. They put one in a few years ago and flew it commercialy.

I went with a Texas Skyways and loved it.

235, no, 265 is the hp rating! and trust me, the only reason to go back to stock is if you are switching aircraft and are taking the engine with you!

If you are buying a plane with it installed, I would not worry. There is a guy here that is on his third or forth, used the plane for Herring spotting and Salmon spotting. He is really holding his life on the engine, so it must be trustworthy.

You can not believe the difference these, (texas skyways/pponk), engines can make
 
aktango58 said:
235, no, 265 is the hp rating! and trust me, the only reason to go back to stock is if you are switching aircraft and are taking the engine with you!

Check the data plate. The -50 is rated at 235 Hp. They didn't want to go through the paperwork to show a larger hp increase.

There is also a mod to put 550 cylinders on a 470 case available
 
Try looking on Skywagon.org. Some of the guys,including stewart b., have discussed this very thing before.

Lance
 
PPONK

I have a PPONK in my Ector L-19 and it is by far the fastest Bird Dog I have ever seen - around 148 GPS mph at 22"/2250. Much faster at higher, but for what?

They balance the engines, and if you have an O-520 case like mine, you have the possibility for 285 pistons. Add Lycon intake polishing and you are off to the moon.

Make certain they jet the carb rich enough. you can lean out, but you cannot richen up if you are short.

Steve Knopp (PPONK backwards) is also very accesible and helpful. :crazyeyes:
 
Cimarron, you might have a miss marked data tag. I have worked on many of these and all have had 265 stamped on them. Supposedly they actually produce more than 265 but to simplify getting the stc they rated it at 265. That is what Steve Knopp told a friend of mine anyway, don't know how true that is.
Shawn
 
A lot of the P-Ponks are converted from 520's. Mine was a TSIO 520 D, it is now an O-520, @275 hp. I guess. The 180 with this engine will go fast ! It all depends on how much you want to spend for fuel.

In case anyone is interested, my 180 is for sale at
www.theplaneexchange.com
J. C.
 
P Ponk

I spent an hour on the phone last Thursday with Paul Knop (Ponk spelled backwards) the owner of P Ponk talking about his STC O-470 conversion for the Cessna 180. You basically can go two ways with this STC and arrive in the same place.

1) Take an O-470K, R or J, pull it apart and install different crankshaft counter weights set up for the harmonics of a three blade prop, bore out the case halves to accept the bigger O-520 cylinders and 7.5:1 pistons, replace the rods with 520 rods, assemble and away you go.

2) Purchase a TSIO-520C (turbo charged 7.5:1 compression) take the turbo charger and injection off and install a carburetor and away you go.

Either way you end up with a carbureted O-520 with 7.5:1 compression that can run auto gas, with a 2000 hour TBO.

The Cessna 185 engine (IO-520) has 8.5:1 compression and fuel injection. He said fuel delivery has not the big difference in the engines hp, compression was the main difference.

He also said on a dyno test the converted 7.5:1 O-520 engine showed 281 HP and a IO-520D (Cessna 185 engine) dyno'd out at 285 hp.

He feels the lower compression 0-520 will run longer because it is under less stress, and has had some come back with over 2800 hours on them and in great shape.

The original O-470 has 7.5:1 compression pistons so this is not that big of change. Just a bigger bore picking up 50 additional cubic inches of displacement (0-470-50).

My big question is whether to get an early light ('53 to 59') 180 or a mid '70s J model that is 350 to 400 lbs heavier but with a modern panel and lower hull time.

Take care! Crash
 
Morning Crash, I have never worried about hull time. I would much rather have an airplane that has had regular use than a hangar queen. More unseen things go wrong with an aircraft that is little used.

I don't know about all P-Ponk conversions, but the two I do know about, both are nose heavy. It may be the big three blade, I didn't weigh mine when I had it off, but I would guess between 100# and 150# for the prop alone. Once you realize the nose heavy condition and balance it with survival gear - whatever - they handle just fine.

I would also rather have a set of good instruments. More than once I have been caught in a weather situation that would have required a big diversion (maybe not enough fuel) or a long wait. I'm not talking about hard IFR, ice, none of these light aircraft are any good for that, just the daily garden variety "I can't see the ground anymore" situations. J. C. GTF
 
Another interesting point is the test between propellers. The 88" three blade pulled the same as the 86" three blade. Paul felt the 86" was the optimum length and after that you didn't gain anything. This might also apply to Super Cubs.

Last week Kascub posted a pull test of 770 lbs with a 90" 1A200. I remember a post some time back that another Cub driver did a pull test with a 82" 1A200 and it pulled over 800 lbs. Is my memory bad or was I just dreaming? Crash

http://www.pponk.com/HTML PAGES/propellers.html
 
Plane pulls

Maybe you could have a competition like they do with the tractors,or just a tug of war on the ground.That would be more exciting than just a scale test. :drinking: :Some of my buddies spend lots of their time pulling it.
 
trust

Testing of Aircraft (max static thrust)
Bob Dempster?s 150 hp SuperCub 74/56 560 lbs
Michael Moore?s 150 hp Stinson ? 580 lbs
John Carson?s 180 hp SuperCub 82/41 880 lbs
John Carson?s 253 hp 182 82 c/s 820 lbs
SGC?s 180 hp SuperCub 82/41 780 lbs
SGC?s 260 hp Pawnee 84/? 800 lbs
BESC?s 235 hp Pawnee 84/? 880 lbs
 
PPonk converted my '57 180A from the original O-470K to a -50 in 1996. I use a 2 blade seaplane prop. I have had no trouble.

I prefer the simplicity of a carburetor, even though carb ice can form and the fuel burn may be a bit higher than a fuel injection. Hand prop starts are also easier, should the need arise. I also consider Steve Knopp to be a trustworthy individual.
 
After reading Kano's post here:

http://www.supercub.org/phpBB2/viewtopic.php?p=55570&highlight=#55570

I'm left wondering if static thrust testing provides nothing more than an opportunity to set around with the lads drinking beer and running up engines on a dyno stand?

Does static thrust testing provide any insight into the blade's AOA change in the various phases of flight?

I guess even if it doesn't testing would be a fun way to kill an afternoon.
 
SB,

Not attempting to shoot down the proposal. Just curious how static thrust relates to Kano's post and admittedly I'm not an engineer. I guess the point you are making is that if static thrust is high then performance on the slow end of the envelope will be good, i.e. take-off, climb and control while slow and landing? I guess to maximize the STOL end of the envelope one wants a prop whose airfoil is generating max lift in take off and landing portion of the envelope? Hence the climb vs. cruise trade off in fixed pitch props.

Anybody have any data on AOA at various points up and down the blade on say a borer 8242? I'm guessing that the AOA on that prop changes when it gets loaded during T/O and the prop flexes; and that the prop flexing under the load is increasing AOA (?) on the prop and creating more lift which is a good thing?

I guess with all these questions, I'm wishing I could pitch up to drink beer and tell stories with you for the static tests - hell I'd even be willing to buy the beer....
 
aktango58 said:
235, no, 265 is the hp rating! and trust me, the only reason to go back to stock is if you are switching aircraft and are taking the engine with you!

Check the data plate. The -50 is rated at 235 Hp. They didn't want to go through the paperwork to show a larger hp increase.

There is also a mod to put 550 cylinders on a 470 case available

The deal with the data plate is that it simply depends on which case you started with. Those going the O-470 route will end up saying 235 on them, and those going the TSIO-520 route will end up saying 265 on them. Since for all intents and purposes they end up in the same config the hp will be the same, but the hoop jumping to make the O-470's reflect that increase would be enormous... This is similar in function to those 200hp for take off only, ELSA's....
I would venture to guess that if a decent shop puts together your pponk you are going to end up with a good chunk higher than 265 available on T/O...

Whiskey Mike, are you missing WM yet? that was one cool bird :)

Take care, Rob
 
We've done 3 of P-Ponk conversions 2-182's and a 180. Everyone is very satisfied and glad they did it. Aero Engines of Winchester has done all the engines.
 
Steve Pierce PPonked my 180 and it Is a dream come true. We used a late model VAR cranked IO520 for the core. It turned the 55 180 into a high speed high performance bird.

Sj


Sent from my iPad using Tapatalk
 
Hi SB,

The TCM data plate shows the T/O HP and the continuous HP. The smaller Pponk 'add a tag' shows Max RPM and CID. Mine says 235, must be a stout 235 :lol: 235 Clydesdales as opposed to ponies?
Take care, Rob
 
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and then add the Cherokee-six fuel injection system(lyc), with a 3/4" spacer to make airbox still fit... and we have 300 if i remember right.... (they have a cont one now too for it? I think?)
 
Mike,you would probably have to add a fuel pump then too I suppose. After a night flight from CT - OH with a lot of carb ice, I wish it were injected!

That has to be an expensive mod though.

sj
 
Stewart

I would be up to a round of Static Tests, maybe I can find a "better" prop for my 150hp cub? If nothing else I can figure out how to drink beers and listen to stories :p
 
Mike,you would probably have to add a fuel pump then too I suppose. After a night flight from CT - OH with a lot of carb ice, I wish it were injected!

That has to be an expensive mod though.

sj

yes its the whole system...
was +10 years ago, pump(s), servo/throttle body? split manifold/fuel pressure/flow gauge, lines, and that riser block.... some old abandoned STC if I recall....
 
SJ,

Mike,you would probably have to add a fuel pump then too I suppose. After a night flight from CT - OH with a lot of carb ice, I wish it were injected!

sj


Hey, leave the carb heat on, or at least partially on, so that intake temperature is well out of the freezing range. Your not going to ingest anything at any reasonable altitude, so there shouldn't be any fear of harming the engine.

Most of these carbureted big bore Continental engines like a little "heat" anyway, helps with the fuel vaporization, giving you better fuel distribution, i.e. they usually run smoother. Yes, adding carb heat does enrichen the mixture, so set the carb temperature you want first, then lean like you would normally, ROP or LOP, doesn't matter. A lot of people have a lot of success around 50 df, mine likes it a little warmer, around 64 degrees.

Get a carb temperature gauge, if you don't already have one, and try it. And if you have a engine monitor, put it in "normalize" mode ( it's more sensitive and reacts more quickly) while you try it and you can watch the EGT's and CHT's smooth out, left side of the engine with right side, while varying the amount of carb heat to find your ideal temperature for the best fuel distribution. Then, it's just a matter of setting the carb heat to that temperature again while in cruise and you leave it there then the ice can't form.

I just leave it on, if carb ice is a concern, all the way to pulling off the runway, keeps it simple.
 
BTW, did anybody notice this thread has been resurrected from 2004? :wink:
 
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Stewart

I'll confess that it probably will be somewhat different for you guys up there in Alaska, where you experience much colder "normal" temps. To the point that adding carb heat may even bring the temperature BACK into the "carb ice" range.

It's just another technique that is often overlooked or worse, not even taught, that will mitigate most of the risk of carb ice. Hell, I'm more worried about starving to death than I am getting carb ice! :smile:
 
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