Hey guys i was wondering if anyone knows what direction to look for the stc for the 470 in a 175
Thanks
Tom

If you don't get an answer here pretty quick, you ought to be able to go to the 175 club and get one,
http://forums.cessnaowner.org/read/1/17 ... 95/quote=1
That might get ya pointed in the right direction
Gary

Follow this link and then put in the make and model of your plane. It lists all STC's available for your plane.

http://www.airweb.faa.gov/Regulatory_an ... enFrameSet

Tom

We have done 2 470 conversions on 175's and I can look up the info for you in my shop on Monday. But, IMHO I would not do that conversion. I would do a 0-360 and lighten up the airframe as much as I could. The 175 does not have enough trim for the 470 and you have to put lead on the tail for the CG. Even at that it is still nose heavy. The 360 is much better in that sense.

Brian

Jaerl wrote:Follow this link and then put in the make and model of your plane. It lists all STC's available for your plane.

http://www.airweb.faa.gov/Regulatory_an ... enFrameSet

I looked up the 182B and only found one STC for engine swap. That was a to take out he 047L and install the O470R. I am sure that there are a lot more engine swap STC's than that. Could have missed somthing.

Tim

Brian - Steve's Aircraft wrote:Tom

We have done 2 470 conversions on 175's and I can look up the info for you in my shop on Monday. But, IMHO I would not do that conversion. I would do a 0-360 and lighten up the airframe as much as I could. The 175 does not have enough trim for the 470 and you have to put lead on the tail for the CG. Even at that it is still nose heavy. The 360 is much better in that sense.

Brian

O360 with fixed pitch prop would be my choice. But you cannot buy a 175 and install an O360 cheaper than you can buy a strait tail 182. No matter what you do to a 175, you will never get a trimable horizontal stabilizer and that is what makes the early 182' so good.

Tim

I agree with Brian. I did an 0-470 conversion and it was a bit heavy. It makes a 2 place plane out of it....but it does climb! I've got the guy's name in the shop. Nice guy, and he lives near Wichita, KS. I can get it later, if you haven't found it.
John

i was just talking to one of my friends and he was trying to talk me into his project 175 and he has a 470 with it, so i was just curious. The IO-390 looks like a nice engine too

Tom

Tim, for some reason the FAA site has two links for Cessnas. One says Cessna Aircraft Company and the other says THE Cessna Aircraft Company. You need to look at both because there are some STC's that only show up on one or the other.

If I was set on doing a conversion, I would look at the Stoots Site. I know they were looking for a 175 to do a New STC Conversion on, and seems like they were just making you pay for parts.

I have to throw my hat into the ring here... the O-360 is probably a much better candidate for that airplane than a 470. I have not flown the 175, so I cannot say with any authority, but I would also strongly suspect that the extra nose-heaviness and lack of trim authority would take away a lot of the benefits that the extra power would give you.

You would likely wind up with an airplane that was not "balanced" both from a CG perspective and a flight handling perspective. I'm sure the (real, actual, experienced) back country Cessna experts will agree that poor handling, nose-heaviness, and flying around with full pitch trim makes for a not-so-good bushplane. When you are actually out in the boonies doing the nasty, you need a good handling, easy flying airplane in order to actually make use of whatever raw performance or raw power you may have.

What I will guarantee you from personal experience is that you will never get the best performance out of the airframe if you are flying at or near the forward CG limit. No way, no how, no chance. The best performance and handling usually comes in at or near the rear end of the CG envelope. This is a well-known, long-established tenet of aircraft performance. Ask any test pilot.

It's kind of like those sportscar conversions where you put a big block Chevy into a Triumph TR6 or the Sunbeam Tiger. You get a straight-line dragster with an incredible 0-60 and 1/4 mile time, but the first time you take it out on a real road you have a car that handles like crap. So you put these huge tires on it, and it finally will go around a corner a little better, but then you need power steering (the trimmable stabilizer that has already been brought up). In this case, you cannot put the power steering on (it would be a very big/expensive project to STC the trimmable tail onto a fixed-tail Cessna).

Another thing to consider is that you can get an O-360 to put out 200-210 HP without too much fuss and without losing any reliability. There was a "stock 200HP" version of the O-360 engine I believe. The STC tuned exhaust systems will give you back a solid chunk of actual power to the propeller that you otherwise had lost with a stock exhaust. A low-restriction intake air filter gives you back a little. There is "porting and polishing" that can be done legally, I think several engine shops have authorization for it. There are propellers available that deliver a little better thrust. I believe there are STC approved "electronic" ignition units that give you some increase in output as well as a touch better fuel burn. All of these upgrades cost some amount of money and/or time to get field approved... but the 470 conversion will also cost a lot.

Once again I cannot speak from personal experience, but I am willing to bet that a 200-210 horse O-360 conversion on a 175 would be a better all-around airplane and with better all-considered performance than a 230 horse 470 conversion.

If you just HAVE to have 6 cylinders, think about the O-540. I understand it is a lot lighter than the 470. You can lighten it up further by using lightweight starters and alternators. For what it's worth, you should probably fly in a 470 conversion before you embark on that project, IMHO.

EZFlap wrote:......If you just HAVE to have 6 cylinders, think about the O-540. I understand it is a lot lighter than the 470......

I don't know about that. I don't have the pertinent specs here, but just from the fact that the 540 has 70 more cubic inches than the 470 I would guess that it weighs just as much if not more.
I would agree that the 470 seems like too much engine for that airframe, & that a O- or IO-360 Lyc would be a better choice. If a 6 cyl is desired think about an IO-360 Continental (like the Hawk XP and T-41B) or a 220 Franklin, if you can come up with the appropriate STC. For power-to-weight it's tough to beat the Franklin, which gets 220hp out of only 350 cubic inches, but there's pro's & cons with any engine or for that matter any airframe.
Like someone said, it'd probably be cheaper to buy an old straight-tail 182 which'd probably be a better all-around airplane than a hopped-up 175 anyway.

Eric

It might easily cost less to buy a C180 that is ready to go...or a Maule.

gb

EZFlap wrote:I have to throw my hat into the ring here... the O-360 is probably a much better candidate for that airplane than a 470. I have not flown the 175, so I cannot say with any authority, but I would also strongly suspect that the extra nose-heaviness and lack of trim authority would take away a lot of the benefits that the extra power would give you.

You would likely wind up with an airplane that was not "balanced" both from a CG perspective and a flight handling perspective. I'm sure the (real, actual, experienced) back country Cessna experts will agree that poor handling, nose-heaviness, and flying around with full pitch trim makes for a not-so-good bushplane. When you are actually out in the boonies doing the nasty, you need a good handling, easy flying airplane in order to actually make use of whatever raw performance or raw power you may have.

What I will guarantee you from personal experience is that you will never get the best performance out of the airframe if you are flying at or near the forward CG limit. No way, no how, no chance. The best performance and handling usually comes in at or near the rear end of the CG envelope. This is a well-known, long-established tenet of aircraft performance. Ask any test pilot.

It's kind of like those sportscar conversions where you put a big block Chevy into a Triumph TR6 or the Sunbeam Tiger. You get a straight-line dragster with an incredible 0-60 and 1/4 mile time, but the first time you take it out on a real road you have a car that handles like crap. So you put these huge tires on it, and it finally will go around a corner a little better, but then you need power steering (the trimmable stabilizer that has already been brought up). In this case, you cannot put the power steering on (it would be a very big/expensive project to STC the trimmable tail onto a fixed-tail Cessna).

Another thing to consider is that you can get an O-360 to put out 200-210 HP without too much fuss and without losing any reliability. There was a "stock 200HP" version of the O-360 engine I believe. The STC tuned exhaust systems will give you back a solid chunk of actual power to the propeller that you otherwise had lost with a stock exhaust. A low-restriction intake air filter gives you back a little. There is "porting and polishing" that can be done legally, I think several engine shops have authorization for it. There are propellers available that deliver a little better thrust. I believe there are STC approved "electronic" ignition units that give you some increase in output as well as a touch better fuel burn. All of these upgrades cost some amount of money and/or time to get field approved... but the 470 conversion will also cost a lot.

Once again I cannot speak from personal experience, but I am willing to bet that a 200-210 horse O-360 conversion on a 175 would be a better all-around airplane and with better all-considered performance than a 230 horse 470 conversion.

If you just HAVE to have 6 cylinders, think about the O-540. I understand it is a lot lighter than the 470. You can lighten it up further by using lightweight starters and alternators. For what it's worth, you should probably fly in a 470 conversion before you embark on that project, IMHO.

Actually, the six cylinder Lycomings are ALL somewhat heavier than the six cylinder Continentals. Do a little poking around on the engine manufacturer's web sites: Lycoming O-540 weighs approximately 405 pounds dry. Continental O470 weighs 369 pounds dry.

I've flown a C-175 with an O-470, both loaded and empty. It was a load hauling machine for short distances, at least, where you didn't have to carry a lot of fuel. The fuel burn of the 470 CAN be nearly that of the Lyc O-360. The airplane climbs like a BOOH (starts with bat) and is fast. With a big load it is great. It is indeed a somewhat nose heavy airplane, but it flys just fine. I'd take one most anyplace, due to the takeoff and climb performance. A good friend owned this one, and asked me to fly supplies out to his remote cabin.

It would be an expensive conversion, as all conversions are these days. As many have said, it's cheaper to buy an airplane that's already been converted.

But for those naysayers, go fly one of these things, and report back. A bit nose heavy, but I'd rather be a bit nose heavy than a bit tail heavy.

MTV

Well, to completly answer the original question....here is the STC information from the FAA database:

Supplemental Type Certificate

STC Number:
SA122NW

This certificate issued to:
Park Robert M

STC Holder's Address:
402 NE 100 Road
Harper KS 67058-8404
United States

Description of the Type Design Change:
Installation of Continental )-470 engine, McCauley propeller, engine mount, cowling, baffles and associated parts.

Application Date:
04/16/1974

Status:
Amended, 11/27/2002

Responsible Office:
ACE-115W Wichita Aircraft Certification Office Tel: (316) 946-4100

TC Number -- Make -- Model:
3A17 -- Cessna Aircraft Company, The -- P172D
3A17 -- Cessna Aircraft Company, The -- 175
3A17 -- Cessna Aircraft Company, The -- 175A
3A17 -- Cessna Aircraft Company, The -- 175B
3A17 -- Cessna Aircraft Company, The -- 175C

Brian

Well, my 175 has 50 more horsepower than the 0360, so even with more engine weight and 11# of lead in the tail it is a great performer. It easily trims to cruise straight and level so I don't know what that's all about. It is on Aqua 2400's which float it like a boss. The 0470 runs a lot smoother than the 0360 in my experience. Not a mechanic, just a bush pilot from the 60's and 70's. Just did a glassy water landing on the Fairbanks float pond last night.

Does anyone have info on this STC holder? Can’t reach them. Has anyone purchased the rights?