The International Cessna^® 170 Association

HI:

I am a 170 wannabe, I have always liked the 170B with the 180 engine.

Can someone give me a performance comparision between the 145HP C-170 and the 180 HP C-170?

The 145 hp only occurs at 2700 rpm....practically meaning no one sees that kind of hp on takeoff. The original engine actually only produces about 120 hp on takeoff.
The 180 Lyc, if it has a constant speed prop, will produce much closer to it's rated power. The differences on takeoff and climb are pretty apparent. The 180 Lyc engined 170A I tested at my home strip used about 2/3rds the takeoff roll/run, and about 1/2 the total takeoff distance to 50 ft as the 145 hp 170B I own.
The cruising speed differences are less dramatic. The 180 Lyc gained about 12 mph and burned 2 gph more to do it. When throttled back to the standard cruise speeds, the fuel burn was also more like the 145 hp airplane.
Accurate performance data is virtually lacking in the increased hp engine conversions. Most of the STC's only state they "meet or exceed" original data for takeoff, climb, cruise, performance.

Thanks for the info.

So what is the REAL world cruise speed for the 180 HP with C/S prop.

75% pwr?
65% pwr?

MP 23" rpm 2400 = 10 gph = 120 mph indicated, constant speed w/7666-2 blades, Gar Aero 850X 10 tires large TW. Not the cleanest plane around.

If you're looking for cruiseing speed, I suggest some other type aircraft.
A C-170 is not much of a cruise speed airplane. Bigger engines are primarily for getting "off and up". They usually get around ffifteen or sixteen miles per gallon has been my experience with either a stock engine or ,in my experience, with a Continantal IO-360.

As for the bigger engine I believe it's what that airframe should have had all along. Except Lycoming didn't make it until 1963 With the stock engine we would cruise at 100 knots at 7500 or 8500 feet and it would labor hard to get higher. Sea level climb loaded would be 3-400fpm. But it would be a good sea level airplane if flown light.

With the Lycoming at those cruise altitudes at 60- 65% it gets around 112+ knots, same MPG, and you can power it up some and go faster if needed to fight a headwind. That's not an insignificant increase in cruise speed. The plane is riding "on the step" not mushing around and it can easily climb higher. Sea level climb at gross is more like 6-700fpm and it's really fun to fly it light!

I have not talked to anyone who has made the switch who would go back.

I could also get into the virtues of a Lycoming O-360 over the Continental
but that's another issue and George and I would get into it again .

My plane is for sale. It is a higher entry cost than most but I think it's also the best value if one can swing it.

Aww, Dave.... let's keep it nice and discuss the pros/cons of the two engines, OK? (Of course, it's a Ford/Chevy probability...)

Lyc O-360 vs TCM IO-360
4 cyls / 6 cyls: 4 cyls is cheaper to overhaul, but 6 cyls is smoother with less vibration for noise/comfort and less likely to cause cracks in cowls, windshields, etc.

valves: Lyc's valve/cam issues, versus TCM's better lubrication in this area.

TBO: Lyc's longer TBO (if both engines overhauled/rebuilt to same specs)

HP: Lyc's 180, versus TCM's 195-210, which gives it slightly better performance numbers at all altitudes.

Fuel system: Lyc's normal aspirations, versus TCM's slightly more complicated, but more efficient, fuel injection system.

Propeller system: Lyc's more Lyceley to have an AD-prone Hartzell.

Availability: Lyc's higher production numbers give it the edge when searching for a used engine to install. The Lyc also has the advantage in finding the appropriate engine mount.

Aesthetics: Lyc's "cheek bubbles" in the cowl and crack-prone (but repairable) fiberglass nosebowls, versus TCM's ability to leave the cowl's external appearance as original.

Cost: About the same, Expensive. $35K-$40K.

gahorn wrote:Aww, Dave.... let's keep it nice and discuss the pros/cons of the two engines, OK? (Of course, it's a Ford/Chevy probability...).

Nope George, you're not suckering me in on this one.

My first 170 I flew home to Washington State from Missouri. It had the stock engine and very low time on it. The plane was a 1952 B model.
It was pretty quiet, and smooth with two people and no luggage. It flew fine but struggled to clear the passes and some of the higher peaks. Its a great plane. Then I sold it and bought one with the Lycoming 180 in it and the 180 landing gear. Hartzel Constant speed prop. The difference between the two is amazing, its a real four place airplane, it gets off the ground quick, carrys four people with alot of power to climb. The cruze is about 130 and gets somewhere around 10 gallons per hour. I have not had it long enough to see its full potential. But I can honestly say that I would not go back to the stock engine, at least in this part of the country, we have alot of mountains and passes. Another thing that suprised me is how smooth the engine is, its the same as the 6 cylinder I sold. The noise is louder you need head phones on. Hartzel now has a 100 hour AD on the constant speed prop as well. You dont have to remove the prop for the inspection. This is my observation on both planes that I owened.

Bill