Continental IO360 vs Lycoming 360

How to keep the Cessna 170 flying and airworthy.

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TerriM
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Continental IO360 vs Lycoming 360

Post by TerriM »

Have any of you converted to a Lycoming 360? Did you buy the STC from Stoots in Fairbanks? It is saturday so I can't reach anyone there to inquire on the cost or what the kit would include.

I'm looking at a 170B with a Continental IO360. It has about 1651 hours on it. That is about 150 hours past TBO. The top has about 851 hours. If I buy it, I would need to be prepared for an overhaul soon or to replace the engine. I'm looking at the cost comparison of replacing with a another mid-time Continental IO360 vs moving to a Lycoming 360. I know the basics like the difference in hp, fuel systems and different prop. I want to know more about the pluses and minuses of each engine/fuel system and what the net cost for a swap might be. It would be interesting to hear commentary on the subject. Nothing like a good debate among pilots! :) Thank you! Terri
Terri M
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c170b53
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Re: Continental IO360 vs Lycoming 360

Post by c170b53 »

I think the availability of the engine kit is the lessor problem as the cost and availability of the engine is the big ticket item. I did talk to Dave at Stoots but I think you would be best to talk to him to get the latest. Dave I believe sells a few STC's his latest requires a new engine thus that's one spendy STC .
Its almost a chicken or the egg situation, need an engine for the stc, need an STC for the engine. The real pain comes in the details as in which prop fits what and what other items need modifying.
In your case you have all the bits, the mods have been done and you're left with the engine O/H, the cheap part, likely a mere 30K. I would look long and hard at what your end game is and what it will cost to get you there before a standard 170.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
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Bruce Fenstermacher
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Re: Continental IO360 vs Lycoming 360

Post by Bruce Fenstermacher »

I think Jim is spot on.

You seam to be contemplating a airplane modified with a VERY expensive STC that most of us only dream of, and you are debating de-modifying it to what many would consider a very nice option and very expensive on it's own, yet lesser than what is already there. Makes no sense. If you feel the engine needs overhaul, overhaul it. Otherwise buy another plane.
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Bruce Fenstermacher, Past President, TIC170A
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Metal Master
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Re: Continental IO360 vs Lycoming 360

Post by Metal Master »

Terri,
I am guessing from your email address that you are in the Seattle area. I have my TCM IO360 converted Cessna 170A at Auburn. Steve my friends who’s 1956 172 Tail dragger we converted to a Lycoming O-360 is also at Auburn if you would like to come and see the differences. Come on down I will be at the airport today after 9:30 AM Today and most other week ends unless I am flying. I will be working on an RV9 today and Steve will be working on a Cessna 140A.
I would not convert from one to the other that has already been converted. Having done and all of the work ourselves. Steve and I are both A&P’s and IA’s, if you are paying someone else to do the conversion. And you were converting a stock airplane to the TCM engine it is a much more complicated conversion. It is a very expensive proposition. Converting a an already Converted TCM IO-360 to a Lycoming engine would be more complicated than just doing a stock conversion to a Lycoming engine as the TCM requires venting system changes that the O-360 Lycoming engine does not require, and if using the Stoots Lycoming IO-360 STC would require system changes not compatible with what has already been performed on the TCM engine installation. The firewall would end up looking like it had been hit with a shot gun blast. If anyone else is around come on down. I should be around after 9:30 AM driving a big white ford cube van the shop truck at mid field hangars north north field hangars.
A&P, IA, New owner C170A N1208D, Have rebuilt some 50 aircraft. So many airplanes, So little time!
hilltop170
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Re: Continental IO360 vs Lycoming 360

Post by hilltop170 »

The Continental is, if I remember correctly, a 210hp engine if turned at full rpm and the Lycoming is 180hp. If nothing else, I would never convert to less hp. There is no substitute for horsepower.

I would love to have a Continental IO360 in my plane. If I was buying that 170, I would not worry about flying it as-is. I would do oil analysis at every oil and filter change and overhaul it on-condition. The cylinders are probably good for a few hundred more hours and the bottom end is tough as we all know. When it starts showing signs, buy a factory new or rebuilt and send that one in as a core, the factory still builds NEW IO360s and fully supports it. I have a buddy with a Hawk XP that has over 2000 hr on the original IO360 and it still runs great with good oil reports.

There would be no positive cost comparison in converting to the Lycoming from the Continental. Buying a factory new Continental would still be much cheaper than converting with a used Lycoming.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
bagarre
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Re: Continental IO360 vs Lycoming 360

Post by bagarre »

Buying a 170 with a Continental IO-360 already installed puts you MILES ahead of the fleet (literally and figuratively)
You're probably several years away from needing an overhaul. If it has an AirMelt crank, you can count on an extra $5k for a new crank so I'd fly it until it REALLY needs overhauled.
I had to split the case on my IO-360 for a prop strike (bought it that way) and a used VAR crank doesn't exist. I ended up needing a new case as well - those are easy to find but the AD requires the AirMelt crank be thrown away at next case splitting regardless of hours.

The big question with that motor, what's the paperwork look like? Was it installed with field approval or STC? There were a few illegal motor mounts so verify the serial number.

It's a very expensive and desirable modification. I wouldn't dream of swapping it for another motor.
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TerriM
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Re: Continental IO360 vs Lycoming 360

Post by TerriM »

Thank you to everyone that responded. Your combined replies increased my knowledge and gave me a lot to think about. Have a wonderful and safe 4th of July. Terri
Terri M
541-639-9045
seattlelights@gmail.com
flyboy122
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Re: Continental IO360 vs Lycoming 360

Post by flyboy122 »

I'd be interested in knowing the weight differences between the two?

I have an Avcon converted Lycoming powered 170. Near as I can tell it weighs about 20 lbs more than stock, with most of that being in the heavy Hartzell constant speed prop. I'm assuming the Continental IO-360 conversion is heavier, but I'd like to see the numbers. More power is great, but since the 170 is limited by gross weight eating too far into the empty weight can leave you with a great performing 2 seat airplane.

DEM
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captsteve
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Re: Continental IO360 vs Lycoming 360

Post by captsteve »

I am nearing the end of installing the Stoots IO-360 in my 170B, with the Hartzell CF prop. Hopefully about 10 more days, I'm doing a lot of deferred items while I've got it all torn apart. Let you know how it goes.

Steve
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