Somewhere I read or heard that the 0200 crank STC made the C85 into a 93hp engine. Is that even correct? If so, at what RPM?
--- In [email protected], Hartmut Beil <hb...@...> wrote: > > > Al.. > > Is 2350 rpm all you can get in cruise? > > You should see at least 2500 if not 2575, which then would indicate best > performance... for a C-85. > > > > On the other hand, a C-90 engine that shares the O-200 crankshaft will be > redlining at 2475, a hundred revolutions slower than a C-85, but due to the > higher torque will still develop 5 horses more than a C-85. > > Interestingly enough the McCauley 71/52 is considered a normal prop on a > C-90, while a cruise prop on the C-85. > > > > It is all torque related I guess. Confusing? Sure. > > > > Last note, 105 MPH is slow in a Coupe that has 85 or more horses. I see 110 > or more depending on environment with a C-85 and a McCauley 71/52. > > > > > > > > Hartmut > > > > To: dongen...@...; [email protected] > From: afl...@... > Date: Mon, 25 Jan 2010 11:00:49 -0600 > Subject: Re: [ercoupe-tech] Re: PROP PITCH > > > > > > > Donald, > > I have a 1947 415CD. It's engine is a C85 with the 0200 STC. It now has 12 > hours on it since major OH. Hartmut recommended I put a 71/52 prop on it for > best cross country cruse. I am happy with the 71/52 performance on this > engine. I gave up just a little bit of climb in order to gain just a little > bit of speed. I am with you, a stickler for not having a draggy plane. SO, I > removed the large venturi, Installed a new round windshield and waxed it to a > military bootcamp shine. It now indicates 105 MPH at 2350 RPM. Before the > improvements it indicated 105 MPH at 2350 RPM. My ASI was checked with my > GPS. SO, no matter what I do the numbers just keep comming out the same. Let > us know how your wheel pants work? > > Al Flora > N94748 > (HYR) > > > ----- Original Message ----- > From: Donald > To: [email protected] > Sent: Sunday, January 24, 2010 8:35 PM > Subject: [ercoupe-tech] Re: PROP PITCH > > > > > > That makes sense. I am a stickler for not having a draggy plane, plans > already to put the sissors fairing back on, wheel pants going on, venturi > horn comes off etc. I have the round windshield, somewhere I heard that is > even a help too. Anybody have any more ideas to make it slide thru the air > easier? I have even found that a good coat of wax helps. > > --- In [email protected], "Ed Burkhead" <ed@> wrote: > > > > > > Besides what Hartmut said, a heavy Coupe with a cruise prop (7151 or > > 7152) may not be able to get up to cruising speed due to load and > > insufficient horsepower to turn that pitch of prop adequately. > > > > While a 1260 pound Coupe might cruise 112 mph with a 7152 prop, a 1400 > > pound Coupe may only cruise at 90 mph at near full power with the same > > prop. > > > > So, if you want the fast cruise, either you need the horsepower to do it > > or a plane light enough to do it with the engine/prop you have. > > > > Each airframe, just like each boat/ship hull, has a range of speed it > > can reach with moderate power. Past that speed, the power requirements > > go up steeply. > > > > Ercoupes and Forneys get to that elbow in the graph somewhere around 110 > > mph. The guy who mounted a 135 horsepower engine didn't go much faster > > than that - he just got humongous climb and fuel consumption (and a very > > ugly plane). > > > > Mark in Wisconsin (who used to work for a previous owner of Skyport and > > who designed the 30 gallon fuel tank system) is one of the few who has > > made a higher power installation effective and he really worked at it > > intelligently. > > > > Me, I was happiest with my C-85 engine and a 7146 prop that gave me > > adequate climb even though my 2400 rpm cruise speed was only 100 mph. > > > > Ed > > > > > > > > > > _________________________________________________________________ > Windows Live Hotmail: Your friends can get your Facebook updates, right from > Hotmail®. > http://www.microsoft.com/middleeast/windows/windowslive/see-it-in-action/social-network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_4:092009 >
