27cc stihl
#3
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From: Moore, OK
its not about what engine you pick that you will have problems putting on your cap 232, its raw power. on any conversion engine to get the kind of vertical you need to hover and such you will have to do some amount of work to get it there. look at the brillelli guys they take conversion engines and port them and tune them to get the most out of them. a standard conversion will not give you the 2:1 power ratio that you need. it will give it enough power to get off the ground and fly in a decent manor and even aerobatics. Definitely not a hover. Start off by building yourself a rig to measure static thrust. take the stihl convert it mostly un-ported, measure it on your scale. then stuff the crank case measure it again. convert it to electronic ignition which wont do anything for you except lower weight. add a slightly bigger bore carb than what is already on it. highest you can probably go on the 27cc is 15 mm. some people remove the gasket between the crank case and the cylinder which increases the compression ratio a bit.
you need to do some reading on engines here is a list of things to do to make an engine more powerful.
http://auto.howstuffworks.com/engine3.htm
some of the things on the list wont apply to you because they are for car engines but the principle applies. You are going to have to experiment a bit to get use of any conversion engine you run. the way to know is going to be ultimately based on static thrust so the best thing you can do is make a rig for yourself like i said to measure static thrust.
you need to do some reading on engines here is a list of things to do to make an engine more powerful.
http://auto.howstuffworks.com/engine3.htm
some of the things on the list wont apply to you because they are for car engines but the principle applies. You are going to have to experiment a bit to get use of any conversion engine you run. the way to know is going to be ultimately based on static thrust so the best thing you can do is make a rig for yourself like i said to measure static thrust.
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From: buchanan,
VA
can i get a 27 cc to hover it it weighs 12.6 lbs with everything tonight i started it it ran good what prop should i use and what do you guys ahve a 27cc on how does it do?
#6
icando3d2 wonders....Can a 27cc engine hover a 12.6 lb airplane? I DO NOT KNOW...but I would start with a 17x6...but that is a wild guess. Good Luck Capt,n
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From: buchanan,
VA
its a hanger 9 cap 232 73 inch wingspan older hanger 9 version, i ran it tonight for the first time the engine has about 2 hours of run time on it in the weedeater and then it was converted it has a zamma carb on it. im posting on this site to learn because trial and error is effective but let downs suck i can put my zdz 60 on it and it would rip the wings off but it will stay on the edge, plus i want the satisfaction of converting my own enigne and having it do what i want to do for alot less money, the prop i ran on it tonight was just an older master airscrew 18-6 just to have it run on the plane ran it about 2 mins, it snowing here so i got really cold behind the prop
#8
That 18x6 may be a little to much for your engine as is. If it is snowy weather I would not run it too much....I would say the engine has to run warm to breake in right. Is there any way you can post a photo of your engine? That may help viewers to come up with more ideas. Capt,n
#11
Here is a engine size to weigt chart............................................. ............................... Around sea level with right fuel and prop, pitts ect.....
With a Moki 2.1 on pitts plane should weigh about 14 pounds or less
With OS 1.6 plane should weight about 12 pounds or less
With OS 1.08 plane should weight about 10 pounds or less
With YS110 plane should weight about 10 pounds or less
With OS .91FX plane should weigh about 8 pounds or less
With SA100 plane should weight about 7.5 pounds or less
With a ST75 plane should weight about 6.5 pounds or less
With OS46FX plane should weigh about 5 pounds or less
With OS25FX plane should weigh about 3 pounds or less
With 50cc gass/pitts plane should weigh about 18 pounds or less
With 40cc gass plane should weigh about 14 pounds or less
With 26cc 1.6 gass/pitts plane should weigh about 10 pounds or less
------------- It may help for 3d type of flying! Capt,n
With a Moki 2.1 on pitts plane should weigh about 14 pounds or less
With OS 1.6 plane should weight about 12 pounds or less
With OS 1.08 plane should weight about 10 pounds or less
With YS110 plane should weight about 10 pounds or less
With OS .91FX plane should weigh about 8 pounds or less
With SA100 plane should weight about 7.5 pounds or less
With a ST75 plane should weight about 6.5 pounds or less
With OS46FX plane should weigh about 5 pounds or less
With OS25FX plane should weigh about 3 pounds or less
With 50cc gass/pitts plane should weigh about 18 pounds or less
With 40cc gass plane should weigh about 14 pounds or less
With 26cc 1.6 gass/pitts plane should weigh about 10 pounds or less
------------- It may help for 3d type of flying! Capt,n
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From: buchanan,
VA
my father in law made the adapter for me from a sketch i gave him, compression its 2 ring engine has 3 hours of weedwacking compression is really good hand starting is a yes, but it does take some butt behind it to hand start does it look ok to you guys im going to get another muffler for it but if you guys don think its enough i may think about putting it on the showtime
#20
Looks like a good conversion. Like you say a different exhaust may be needed. May give it more power too. How much does your showtime weigh? Also the wing area. Its a good idea to figure wing loading. Capt,n
#21
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From: buchanan,
VA
im not sure about weight on the showtime, i used to fly the cap with a 1.20 surpass fourstroke engine and it had verticle but not impressive i was going to install a 1.6 glow but being newly married money doesnt allow the purchase. The 27cc is a 1.648ci give or take the last few digits so hopefully i can get a fish scale and get some numbers for you guys i have found a apc 18-6 on my 1.20 so im going to try it tomorrow if time allows
#24
As far as I know they are. I know I have seen all types of engines at fly-ins. Maybe of more importance is the Radio and servo instalation. I think most events have a inspector to check this out. Well I got to sut down for the nite. Take Care Capt,n
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From: buchanan,
VA
well i flew the cap today it flew well had good power for normal aerobatics not a chance in the world on hovering or vertical pulls it weighs in at 13 lbs even going to leave it in there to have a great conversation piece, going to convert another and stick it in another plane thanks for everyones input any questions on the conversion ill try to help



