O-360 install

How to keep the Cessna 170 flying and airworthy.

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daedaluscan
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Re: O-360 install

Post by daedaluscan »

Vertical wrote:I would very much appreciate if you could continue to provide your impressions of the performance changes as you fly more. -Climb rate, full burn, range, CG, GW handling etc..

Also, are you on 8.50's?

With an average o300a overhaul nearing $30k (that's if your crank, cam, & pan is good), I'm thinking hard on switching over to the o360 in the next couple years..Seems like a guy could start stockpiling parts and then sell his o300 to take the sting out.

Thanks!
Sure, but I am just calibrating FP5L now, so no accurate fuel burn. Give me a week or two.

I am on 8.50s, but have a pair of Goodyear 26 that may go on.

That was my thinking, but the STC is not cheap. I used the Delaire one, and even though it was very complete you need a prop and governor and the incidentals add up. I also did a new battery, some gauges and then there is paint.

It does feel like a different airplane, I am not sure if it noisier but it feels like it maybe. It is definitely faster and way quicker to accelerate.Once I get a few hours on the engine I will start to experiment with lower power settings and see where the fuel burn at different speeds is.

I will look at cruise trim tomorrow Jim, I will probably headed out to the west coast, Vargas and Nootka. I delivered a 200+lbs outboard yesterday and the flare was way smoother. I think a permanent survival kit is in my future.
Charlie

1956 170B C-GDRG #27019
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Vertical
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Re: O-360 install

Post by Vertical »

Great. Look forward to it. In general were you happy with the DelAir kit?

I have have good paperwork for 337, testing and approvals on the 26" goodyears if helpful. Although, not sure how you roll (so to speak) in Canada. I ran through a pair of the GY 26's. You might appreciate double pucks.
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ghostflyer
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Re: O-360 install

Post by ghostflyer »

I have done the “harry,s Delicker” STC to my aircraft and now being involved with some modification of others but using the Stoots STC also. Harry,s kit turned up in a big box and it looked like some one had just thrown the parts in . I had a few issues with Harry,s STC and phoned Harry a number of times for clarification . My biggest issue was no3 CHT being very hot . I listened to a number of helpful people and did all sorts of measurements of airflow /pressure /temperature in all places of the engine that I could think of . Success at last. In our shop We have fitted a number of Stoots STC,s to early model cessnas and it was comparison time between the STC,s . We found the Stoots one better explained and not so many anomalies in the supplied parts list . For some reason just about every STC ed aircraft here has fitted a fixed pitch prop including my self . For for the best part, you will outrun a Cessna 172 in speed and climb. It could have something to do with that dragee thing on the front called a nose wheel.
One thing I have found in cruise is set your RPM and let everything settle down. Lean for the best outcome for the engine . Then trim slightly down and allow for a very minimal decrease in altitude [less than 100 ft] then slight pressure back pressure on the control column to maintain height. Then watch your air speed increase . Some times the engine RPM will increase very slightly. The best results are around 7500ft to 8500ft .
bat443
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Re: O-360 install

Post by bat443 »

Vertical wrote:Great. Look forward to it. In general were you happy with the DelAir kit?

I have have good paperwork for 337, testing and approvals on the 26" goodyears if helpful. Although, not sure how you roll (so to speak) in Canada. I ran through a pair of the GY 26's. You might appreciate double pucks.
Hi Vertiical. I would greatly appreciate it if you could send me a copy or your 337 for the Goodyear 26 tires on a 170B, also the supporting data if you could. I have a 54 170B with a o360 and a 80 inch Hartzell. I couldn't be happier with it :D . I already have double puck brakes. Thank's I sent you a pm with my email address

Tim
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Vertical
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Re: O-360 install

Post by Vertical »

Just emailed it to you Tim. It also the approval for the Gar Aero bush tail wheel (big fork on a scott 3200). It's a cheaper alternative to the ABI/Baby bush wheel if you can find one.
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Vertical
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Re: O-360 install

Post by Vertical »

ghostflyer wrote:
One thing I have found in cruise is set your RPM and let everything settle down. Lean for the best outcome for the engine . Then trim slightly down and allow for a very minimal decrease in altitude [less than 100 ft] then slight pressure back pressure on the control column to maintain height. Then watch your air speed increase . Some times the engine RPM will increase very slightly. The best results are around 7500ft to 8500ft .
Ghostflyer, What are you getting for cruise speed and fuel burn when you hit that "sweet spot"? You say this is with a fixed pitch?
bat443
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Re: O-360 install

Post by bat443 »

Many thanks Vertical. When (if) I get caught up, may have to do it before I get caught up :) I will fill out a 337 and submit to my PMI, then it is up to them.

Tim
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ghostflyer
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Re: O-360 install

Post by ghostflyer »

Vertical,
I normally cruise at 2450 rpm at 7500ft to 10500ft depending on thermal conditions. My fuel consumption is normally around 34 liters to 37 liters which in American terms
Is about 9.2 us. gals a hour. I run a sensenich fixed pitch with a pitch of 60ins . My TAS is around 120 kts depending on load and OAT. It’s a rocket with just me on board and 1/2 fuel. Even thou I have toyed with the idea of fitting a MT prop [maybe reverse thrust] ,I can’t justify the added expense and weight increase as with the engine and a fixed pitch prop at 2250 rpm initially at the start of take off it has enough grunt to have a reasonable short take off roll. Please note.. on take off with WOT. Fuel is consumed at 15 us gals a hour.
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daedaluscan
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Re: O-360 install

Post by daedaluscan »

Vertical wrote:Great. Look forward to it. In general were you happy with the DelAir kit?

I have have good paperwork for 337, testing and approvals on the 26" goodyears if helpful. Although, not sure how you roll (so to speak) in Canada. I ran through a pair of the GY 26's. You might appreciate double pucks.
Still calibrating FP5L, but I think I am close. Today saw 10.7 gal hr at 24 square, 115 mph. Still running it purposely rich, I hope to get under 10.
No 337 here in Canada.

I bought the Delair kit from someone who’s had it prior to me. It was very complete and with all the paperwork. Chris then changed the STC to my airframe for $100, and was generally very helpful and kind. The paperwork was a set of plans and very basic instructions. Totally adequate, but as with all of these things you would do the second one faster and better. I wish I could have talked to someone who had done the cowling a few times.

The mount, baffling, nose cone and all of the hardware were very nicely made. When I say complete I mean hoses, wire, terminals, rivets, screws for baffling. It saved a ton of time sourcing these parts. I did a few other things at the same time, added FP5L and UBG16, went to breakers, lots of rewiring, reinstalled a glove box and that all took time.

I had considered the Bush STC as I am naturally cheap, but I think by the time you found everything you would be close in $$ and have spent a lot of time getting there. If I could have found a way to do it here in Canada I would have gone hollow crank with a fixed pitch for the time being, but I could not work out how to do that.
Charlie

1956 170B C-GDRG #27019
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ghostflyer
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Re: O-360 install

Post by ghostflyer »

The strongest advise is do not go any where near the Bush modification. I think it has been well and truely addressed on this web forum. I have a manifold gauge fitted [fixed pitch] and at 2400 rpm it’s showing just under 23 ins and cruising about 115 kts. Verified by 2 GPS and flying a triangle course. You should get it under 10gals [us] a hour .
I had to run my engine around 1800 rpm once due thermal activity and keeping my speed down and the fuel economy per hour was staggering . But it took me nearly all day to get there and the wings stayed on.
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Vertical
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Re: O-360 install

Post by Vertical »

I look at the C170b with an o300 and an 80/4x prop very loosely like the below for off airport, soft ground with no obstacles. Figure sea level, normal temp.

1 person and low fuel 200' landing or take off (TO)
2 ppl and low fuel 500-600' TO
2 ppl and camping gear with mid fuel 700-800' TO
3ppl and mid fuel 900-1,000 TO
3ppl and camping gear (near gross) 1,000-1,100 TO
4ppl at gross (no gear mid fuel) 1,200 TO

Not trying to get too technical with distances. However, can anyone tell me whether their o360 with a CS prop appreciably changes this general equation?

Basically, does the conversion allow you to change your mission like adding a person or more gear or more fuel and fly into places you previously could only go to with one less person/gear/fuel etc.?

I know..lots of missing critical information and every pilot and plane is different... Just looking for relative, anecdotal performance information since I don't think there is a AFM with any of the conversions. Or is there?
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daedaluscan
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Re: O-360 install

Post by daedaluscan »

I went from a stock 170B to a Sportsman and then to an 80x42. Both produced noticeable improvement, and at sea level with half tanks it was a Hotrod. At 10k plus DAs it required a lot of careful planning. Totally practical but I never felt comfortable without at least 2,000 ft of runway at altitude.

I have about 10 hours on my O-360 with Hartzell 76” CS, all at sea level, and it has completely transformed the airplane. It really feels more like a 180. The acceleration from standstill is totally different. If I can ever get back to Idaho I think I will be visiting a lot more shorter strips.
Charlie

1956 170B C-GDRG #27019
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GAHorn
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Re: O-360 install

Post by GAHorn »

It’s a big investment to ovhl an engine... it’s a much bigger one to modify to a different engine...

It may be helpful when making this decision to recognize that Weight is directly related to performance. A standard C-145 / O-300 combined with a standard 53” pitch prop will do better than the statistics in the book.... IF the airplane is lightly loaded.

The last 200 lbs of Weight that brings the airplane up to 2200# really turns it into a plane that can barely meet its’ published data...and that feels very sluggish to the pilot.

Most of these airplanes have gained weight over the years at such a gradual rate that it fools us into believing the engine is weak...when in reality it’s the airplane that’s heavy. The computed Wt/Bal data on the airplane is almost always wrong ... causing us to believe the airplane is lighter than it actually is. On TOP of that, we have added things to the baggage shelf, to the baggage compartment (that spare bottle of oil, the tie-down-ropes, tool kit, spare tailwheel tire, tie-down stakes?, etc etc .... and then there’s that forgotten junk under the rear seat.... and like our planes... WE have gained weight over the years.... It all adds up to marginal-performance.

Before investing in a $50K engine, it may be surprising to have a good house-cleaning and lighten-up. :wink:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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ghostflyer
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Re: O-360 install

Post by ghostflyer »

Hang on George, some of us are still trim taught and terrific and look like we are still 21. I replaced my “clean” carpet and weighted it before disposal and it weighed heaps and the replacement [new] carpet was a about 1/3 of the weight . The new carpet didn’t have that thick foam backing glued on to the carpet as the old carpet did. The new carpet noise reduction was about the same as the old carpet .
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Vertical
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Re: O-360 install

Post by Vertical »

Yeah..I've already stripped out most of non-essentials I can find...I'm to the more expensive or impracticle items like rebuilding your seats with no springs, going to the gym more, titanium gear legs...or stripping my 2017 paint job off (not going to happen)...

I guess I'm just hoping to hear: Yep, along with a few other mods, doing the conversion gets you 2/3 of the way to a 180 mission, but still retains all the best characteristics of the 170 you know and love..
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