GT80 props
03-12-2003, 09:58 PM
#1
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GT80 props
Hey guys,
I picked up a GT80 with no manual, and it came with a couple 24x12 props. Since this is being used in an aerobatic application, I was wondering if anyone has had success swinging a 26x8 prop? All I got from the Horizon website was 24x10. Looks like a very good quality power plant!
I picked up a GT80 with no manual, and it came with a couple 24x12 props. Since this is being used in an aerobatic application, I was wondering if anyone has had success swinging a 26x8 prop? All I got from the Horizon website was 24x10. Looks like a very good quality power plant!
03-12-2003, 11:01 PM
#2
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24-12 is way too much prop for aerobatics..The 26-8 would be much better..
Direct quote from Zenoah instructions.."This engine procuces the maximum output when the engine is running at about 10,000 rpm..Be sure to use a propellor which makes the engine speed approximately 7000-10,000 when the airplane is flying"
Backyard engineers who try to run the Zenoah twins at 6000 with the wrong prop complain that the engine has no power..
The Zenoah is not a 3W or DA or ZDZ..Run it like they say and you will be happy..We run the 445s (glow fuel) at 11,000 rpm in our racers, and nothing else out there is competitive..Not ZDZ, not 3W, not DA, or anything else. Closest engine was a Quadra 75, but they had to run up to 50% nitro to stay close.....Our class engine limit is 81ccs, no tuned pipes, just an 8 inch (or less) open header...Speeds are 175 mph, radar clocked....The new stock gas class uses Zenoah 80s, speeds are in the 155 mph range...Props are in the 20-18 range, rpms 9000+, just like Zenoah calls for......
Direct quote from Zenoah instructions.."This engine procuces the maximum output when the engine is running at about 10,000 rpm..Be sure to use a propellor which makes the engine speed approximately 7000-10,000 when the airplane is flying"
Backyard engineers who try to run the Zenoah twins at 6000 with the wrong prop complain that the engine has no power..
The Zenoah is not a 3W or DA or ZDZ..Run it like they say and you will be happy..We run the 445s (glow fuel) at 11,000 rpm in our racers, and nothing else out there is competitive..Not ZDZ, not 3W, not DA, or anything else. Closest engine was a Quadra 75, but they had to run up to 50% nitro to stay close.....Our class engine limit is 81ccs, no tuned pipes, just an 8 inch (or less) open header...Speeds are 175 mph, radar clocked....The new stock gas class uses Zenoah 80s, speeds are in the 155 mph range...Props are in the 20-18 range, rpms 9000+, just like Zenoah calls for......
03-13-2003, 12:57 AM
#3
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I saw one of the Team JR guys running a GT-80 on a 33% H9 Cap. It had a relatively small prop - I think Mejzlik 22x10 or 23x10.
As Rcign pointed out, this would let the engine rev up into the meat of the powerband. Also, get a free-flowing muffler. H9 recommends drilling holes in the stock muffler baffles to let it breathe and make more power.
As Rcign pointed out, this would let the engine rev up into the meat of the powerband. Also, get a free-flowing muffler. H9 recommends drilling holes in the stock muffler baffles to let it breathe and make more power.
04-26-2003, 12:40 PM
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I have a brand new GT-80 mounted on a glider tug. Yesterday I made the first flight with a MenzS 26x8. The engine spins this prop just a tad below 6000rpm and produces 33lbs of thrust which is plenty for a 24lbs towplane. Actually I use the same prop for my G-62 and it is my favourite prop for towing.
04-28-2003, 03:35 AM
#10
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GT80 props
So far I'm not happy with my Bolly 24x12. Once the plane gets up to speed it does fine, but at low speeds (harrier), when I jam the throttle it takes a while to spool up to where it is producing respectable power. I'm going to try my Mejzlik 24x12 next, and if that doesn't do it then the props will go up for sale and I'll try a 24x10.
