GMS .76 initial readings
12-11-2003, 11:44 PM
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GMS .76 initial readings
Two GMS (Gemtec Machine Systems) .76 engines on test stand
Two 10 ounce tanks of Morgan Omega 5%
Stock muffler
SonicTronics 310 glow plug
APC 13 x 8
Both ran at 10,700 rpm and idled cleanly and continuously at 2200.
This approaches the performance of a .91! I fully expect to run a 13 x 7, now installed in a GP60 Stik at over 11,000, once the weather cooperates here in MI.
Best of all, a half ounce lighter than a TT.61 Pro and $82!!
Regards,
DrGO
Two 10 ounce tanks of Morgan Omega 5%
Stock muffler
SonicTronics 310 glow plug
APC 13 x 8
Both ran at 10,700 rpm and idled cleanly and continuously at 2200.
This approaches the performance of a .91! I fully expect to run a 13 x 7, now installed in a GP60 Stik at over 11,000, once the weather cooperates here in MI.
Best of all, a half ounce lighter than a TT.61 Pro and $82!!
Regards,
DrGO
12-22-2003, 12:12 AM
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RE: GMS .76 initial readings
Dang...that,s pretty good...I imagine you would see about 700-100rpm's with a tuned pipe, if that's the case then at $88.00 you gettin on hell of a motor. Here is what I posted in the other forum. as you can see with a sotck muffler and an O.S 7l carb the GMS aint lookin to bad.
With the stock muffler minus the baffle I get 11,300 with an APC 13/8 and 15% Omega, the 11,300 is maxed out...for flying I richen it down to 10,800. About the only complaint I have is the vibration at idle. BTW...I am using an O.S. 7L carb.
Spacewalker...that is one hell of an increase in RPM's...I think I might have to get on of those mufflers...I am mounting a pipe in it now but I doubt that I will see 1000RPM increase.
After mounting the Macs muffled pipe I am now getting 12,100 maxed and about 11,800 ready to fly...I was going to do a maiden flight today and test the tuned pipe setup but the wind is really cranking 25mph and gusty...so ot will have to wait.
With the stock muffler minus the baffle I get 11,300 with an APC 13/8 and 15% Omega, the 11,300 is maxed out...for flying I richen it down to 10,800. About the only complaint I have is the vibration at idle. BTW...I am using an O.S. 7L carb.
Spacewalker...that is one hell of an increase in RPM's...I think I might have to get on of those mufflers...I am mounting a pipe in it now but I doubt that I will see 1000RPM increase.
After mounting the Macs muffled pipe I am now getting 12,100 maxed and about 11,800 ready to fly...I was going to do a maiden flight today and test the tuned pipe setup but the wind is really cranking 25mph and gusty...so ot will have to wait.
09-25-2006, 08:43 PM
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RE: GMS .76 initial readings
You want the 14X4 because the 13X4 will go supersonic and let the engine rev into an rpm range that it wasn't designed to run an it will quit.
