Engine upgrade: To Pponk or Texas Skyways?

txflyer

txflyer

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Fly it like you STOL it ♦
So when our Cessna 0-470-R continental is ready, which one would you use? The Pponk super eagle 0-470-50 conversion? Or the Texas Skyways 0-520-F/TS upgrade? I know they have an STC for an IO-550 now, but that's too much $$$$. :eek:

The Skyways 0-520-F/TS engine has 500 more TBO than the Pponk. I have not priced any of this with either Pponk or T.S., so I may be comparing apples to oranges.

Any other alternatives? I'd like to hear from y'all and anyone who's done this. Something bigger is definitely going up in the squirrel cage when it's time.... Maybe RR or somebody will come up with a 300h.p. $40,000.00 turbine or diesel between now and then, but I doubt it. :dunno:

Thanks in advance. :)
 
I would Pponk, because I can use my own engine (modified)

Last I looked the Texas skyways was only a new engine ($$$)
 
I have the -50 with 3-blade. Amazingly smooth.
 
Skylane81E said:
I would Pponk, because I can use my own engine (modified)

Last I looked the Texas skyways was only a new engine ($$$)
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That confirms what I thought. It's a factory new 0-520 right?

I guess that's why the extra 500 TBO.

If that's the case, I could buy a new one and put it in here. Ron and me could do it cheaper than them I'll bet.
 
wabower said:
I have the -50 with 3-blade. Amazingly smooth.
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I just upgraded to the two blade MT for this purpose. For my 180, it was a perfect fit. It shaved 11 pounds off the foremost CG station, which is huge, and you can feel it. And being composite, the MT is lighter, and spins up faster. It also spins down faster. When you pull the throttle, it's like you dropped anchor.

The 0-470 is a little light in the ass for a three blade, but it mates with the two blade like butter on bread. And when you upgrade, the two blade MT can handle anything you throw at it. So that's why I went with a two blade. So I can have my cake now, and eat it later too. :yes:
 
txflyer said:
That confirms what I thought. It's a factory new 0-520 right?

I guess that's why the extra 500 TBO.

If that's the case, I could buy a new one and put it in here. Ron and me could do it cheaper than them I'll bet.
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Extra TBO is because of the "total drain" oil pan, they have an STC (only available with the engine swap) to put a drain on the low point of the sump, rather than to the side.
 
Skylane81E said:
Extra TBO is because of the "total drain" oil pan, they have an STC (only available with the engine swap) to put a drain on the low point of the sump, rather than to the side.
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Thanks Duncan. I didn't know that, and was not clear on that.

Makes it convenient for them to hold that STC.

What's to stop a man from welding/relocating his own sump I wonder then...?
 
txflyer said:
Thanks Duncan. I didn't know that, and was not clear on that.

Makes it convenient for them to hold that STC.

What's to stop a man from welding/relocating his own sump I wonder then...?
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No STC
 
PPonk it
Cost is about the same as an engine overhaul, unlike TS
 
moonshine said:
PPonk it
Cost is about the same as an engine overhaul, unlike TS
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That's what I figured since that's what everybody does.

One thing I'm learning about airplanes is sometimes it's better to swim with the salmon, even if it's not the uber gizmo you want ...... :redface:
 
Every skywagon owner I know (all two of them) who have the super eagle conversion, are happier than a pig in ****.
 
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Skylane81E said:
Won't buy you the extra TBO time though
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It would be a good upgrade if you could put one on a Pponk 0-470-50.

Draining every drop of old oil sounds good to me, and maybe worth the effort if it can be done.

The tail low stance of the skywagon lends itself to a drain plug right in the back center bottom of the sump. Every drop would come out then. :redface:
 
txflyer said:
It would be a good upgrade if you could put one on a Pponk 0-470-50.

Draining every drop of old oil sounds good to me, and maybe worth the effort if it can be done.

The tail low stance of the skywagon lends itself to a drain plug right in the back center bottom of the sump. Every drop would come out then. :redface:
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It won't hurt with out a doubt, and I think that the extra time you get with it is more likely an indication of how long the engine actually lasts with good care. So far I've been involved with the OH of a whopping thee engines before TBO. One was prop struck with only about 150hrs left, made sence to do it wile the insurance company was paying for the removal and tear down anyway, second was the same engine when a starter mount stud stripped out of the case and a helicoil repair wasn't possible. Again it was just before TBO, so let's do it while it's apart anyway. Third was a plane going on the market with an engine about 200hrs left, done for marketing reasons.

There have been others that needed fairly major work prior to TBO, hell one that never flies is on its third set of jugs in 500hrs due to rust:mad2: and on 135 planes calendar time comes in too
 
Guiding principles:

Only one what can get a Mogas STC.

I'd almost ignore TBO times, as 91 ops it is a non issue. You will fix/replace it as needed by condition.

Do both options include porting, balancing or blue printing the rebuild?
 
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Skylane81E said:
Won't buy you the extra TBO time though
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True, but if you're part 91 it may buy you some extra life, which is even more important. :)
 
Engine upgrade: To Pponk or Texas Skyways?
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Can either legally burn MoGas?

Might be something to consider if ethanol free MoGas is available in your area. I've saved enough money during my current 1,100 hour run of my O470L to pay for about 1/2 of the overhaul (I average about 50% MoGas).

And...

It's still running strong...
 
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When I was plane shopping, a guy whose info I was inclined to believe told me that Knopp designed the -50 for mogas but that his STC was being delayed by the FAA over some BS detail so he agreed to drop the mogas if they would just approve it so he could sell some engines and generate some cash flow.

We can't get no-corn gas around here anyway, so it wasn't a big deal at the time but might be worth a follow-up to decide what's possible without damaging the motor.
 
We have 750 hrs in 4-1/2 on a Pponk made by Steve Knopp's shop. Couldn't be happier, it's been a great engine. Of course, now we're faced with the idiocy of the proposed AD on the ECi jugs we installed (which we've had zero problems with), but that has nothing to do with the Pponk design.

My understanding is also that it would likely run just fine on non-ETOH mogas, but that's not in the cards (legally) for now.

We have a 2-blade McCauley on it, fwiw.

Jeff
 
Where I send them they all turn experimental and no-one cares what the STC says
470-50 is a low compression carb'd engine
YMMV and you do the math
 
Reading Pponk's site, they honor a 180 day or 240 hour warranty on the engine. Whichever comes first.

I can't find any nitty-gritty specs on their site like what jugs they're using.
 
If you're this far into the swap, you should give some thought to whether you want to be carbed for another engine life. If I were doing it, the answer is no. I've had no problems with the 470-50 but injection is just better. And yeah, I could change it out now, but the engine has less than 400 hours and I'm simply not going to throw that much money at it without some provocation. But if you want a nice low-tiime -50 we might figure out a way to make both of us happy.

txflyer said:
Reading Pponk's site, they honor a 180 day or 240 hour warranty on the engine. Whichever comes first.

I can't find any nitty-gritty specs on their site like what jugs they're using.
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wabower said:
When I was plane shopping, a guy whose info I was inclined to believe told me that Knopp designed the -50 for mogas but that his STC was being delayed by the FAA over some BS detail so he agreed to drop the mogas if they would just approve it so he could sell some engines and generate some cash flow.

We can't get no-corn gas around here anyway, so it wasn't a big deal at the time but might be worth a follow-up to decide what's possible without damaging the motor.
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You might try Pelican Landing.
 
wabower said:
If you're this far into the swap, you should give some thought to whether you want to be carbed for another engine life. If I were doing it, the answer is no. I've had no problems with the 470-50 but injection is just better. And yeah, I could change it out now, but the engine has less than 400 hours and I'm simply not going to throw that much money at it without some provocation. But if you want a nice low-tiime -50 we might figure out a way to make both of us happy.
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I guess it would be pretty stupid to yank my 0-470-R out and sell it with another several hundred hours to go on it. But I would sure like more power!

If I got a wild hair, I could upgrade for just ****'s and giggles, but it wouldn't be too practical. :redface:

You want the IO-550 I'll betcha. Are we ever happy? That's the thing I like about the skywagons. You can put everything, and the kitchen sink on one.
 
wabower said:
If you're this far into the swap, you should give some thought to whether you want to be carbed for another engine life. If I were doing it, the answer is no. I've had no problems with the 470-50 but injection is just better. And yeah, I could change it out now, but the engine has less than 400 hours and I'm simply not going to throw that much money at it without some provocation. But if you want a nice low-tiime -50 we might figure out a way to make both of us happy.
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IO-550 C180 flies very nice, but tends to be nose heavy (think if you are comfortable with carrying lead in the back) and you do need to watch those CHTs at lower alts in hot climates.
You might already know all that but I figured I'd throw my 2c in :)
 
Thanks, I really hadn't looked into it further than talking to Tom Clements (the King Air guru and friend) about his plane that he likes a lot after the new engine install.
moonshine said:
IO-550 C180 flies very nice, but tends to be nose heavy (think if you are comfortable with carrying lead in the back) and you do need to watch those CHTs at lower alts in hot climates.
You might already know all that but I figured I'd throw my 2c in :)
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Henning said:
Why are they using extra low (7.5:1) compression cylinder assemblies?
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You get a 275hp engine as a result of mating 470U crankshaft to low comp 520 cylinders. De-rated for longevity, I guess.

O-520/TS sports GTSIO-520 jugs if I remember right
 
Sounds like that low compression engine would be suited well for a turbocharger.

Or if you wanted a one of a kind, get a field approval for Forced Aeromotive's mechanical super charger. They have an STC for 182's, but not 180s or 185s.

I looked into their supercharger, but backed off because of the no STC for my plane. Rod told me when they filed for the STC on the 182, they just made a stupid oversight mistake and did not apply for the 180/185 not knowing they could have, since it is the same airframe. Now, they don't want to have to do it all over again.
 
I see in 2002, Pponk issued a service information letter recommending tear down and rebuild of effected conversion engines due to the wrong crankshafts and 8.5 compression pistons being installed. :eek::dunno:
 
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