hornet dave
Posts: 21
Joined: 12/18/2007
From: Pittsburgh, PA, USA
Status: offline
|
Here's my recent experience with the 160, copied from the xtremeflight yak 54 thread:
A while ago I was complaining about a lack of power with the OS 1.60 FX. I've got it sorted out and working well now, but I'll give a quick summary of my errors just in case it helps someone else down the road. The motor is pumped with a vp-30 and runs nicely across the whole throttle range. Now that it's warm, it starts real easily by hand.
Configuration #1:
Bisson Pitts, ends of exhaust stacks drilled out, wildcat xtra 10% fuel. It would barely pull out of a hover, I really didn't have any confidence to hover anywhere near the ground. It would tach at about 8550 rpm with the apc 18X6W (1000 ft msl, 75 degrees).
Configuration #2:
I tried a TurboJett muffler. It didn't help. I lost a couple hundred RPM. Going to 20% nitro Magnum brand fuel got most of the RPM back, but in flight, the motor didn't unload nearly as much as the Bisson, so I had to pretty much use full throttle for any traditional aerobatics.
So a couple days ago I did some testing of the mufflers at the field - thrust figures are far from being accurate, the grass was rough and the wind blowing in different directions. The zinger 18X6/10 was chosen just to load the motor down into the mid 7k rpms to see how the mufflers compared, I never did fly it. (all measurements at 1000 ft msl, 85 degrees F, quite humid) :
Turbo-Jett Muff and 10% wildcat xtra fuel:
Zinger 18X6/10 7250 rpm 13 lbs thrust
APC 18X6W 8340 rpm 15 lbs thrust
Bisson Pitts w/ 10% wildcat xtra fuel:
Zinger 18X6/10 7400 rpm 15 1/4 lbs thrust
APC 18X6W 8550 rpm 17 lbs thrust
So, still not being happy with the power, I mixed about 2 parts wildcat xtra 10% with 1 part Magnum 30% heli plus fuel, which should produce 16% nitro I think.
Bisson Pitts w/ 16% mixed fuel described above
APC 18X6W 8800 RPM (no thrust measurement taken, should be around 19 lbs)
Now I'm happy!!!!!!!!!!!!!!! After all that screwing around, all I needed was a little more nitro. The funny thing is that in other threads, people report that this engine does not respond much to nitro, but I found that going from wildcat 10% to either magnum 20% heli or adding magnum 30% heli to the wildcat fuel will get me 200 rpm or so. The turbo-jett turned out to be a huge, heavy dud. It might be of use for those that need a quieter muffler, but it's down on power compared to the much cheaper bisson.
I'm not too terribly sure on this, but I think I lost 100-200 rpm when I switched from 10% magnum airplane fuel (used for breakin) to the wildcat 10% xtra. I've got more magnum fuel now, so I'll be able to try that again one of these days.
Now I'm having fun flying the airplane and i'm looking forward to burning some fuel.
|
Printable Version
All Forums >> Glow Engines, Gas Engines, Fuel & Mfg Support Forums >> Tachometer Readings >> RE: O.S 1.60FX Owners. Post your tach readings 
RE: O.S 1.60FX Owners. Post your tach readings - 
