apereira

Hello Troy,

Do you think this is too much oil, I know the recommendation is 20-24%, but I just tried the fuel and felt the engine was laking a little power, 17x12 7760RPM.
I switched from 30/20% and field, this is higher field elev but 1200Ft, not that dramatic anyway.
I wonder if that 3% more oil really decrease power a little.


Regards

Troy Newman

It depends on the oil. If its the Low Viscocity oil then I think its good. I use the Cool Power 30% Performance Heli blend and its a 23-24% oil content due to its low viscocity oil. However this much oil in a higher viscocity oil is likely a little too much oil.

I don't have experience with the Powermaster blend you are referencing.

The YS rules are 20% oil content minimum as a recommened fuel. What you choose to run is up to you beyond that.

I have no idea what engine you are running so I can't say if your numbers are out of the range where they should be. A 140DZ on a 17-12 is about right for the RPMs you are showing. A 160DZ its a little low maybe 200-400 depending on the time on the engine and how its setup. A 17-12 Prop at 7800 is a pretty good pull for the F3A sequences. Its also quiet at this rpm too. I normally will run the 17-18" props at this 7700-7800rpm and it makes the noise limits and pulls the models very well.

Troy Newman
Team YS

apereira

Thanks for the quick response Troy,

Yes it is low viscocity oil and it is the the 160, when setting the high needle valve, I was opening until I heard a slight increase in RPM when pinching the fuel line, the thing is I can not have the option of a dead stick because of our field, is like a aircraft carrier.

What method would you recomend to set up the high speed needle?

Thanks again

Troy Newman

I don't do the pinch thing with the YS engines.

I slowly lean the mixture using a Tach till the engine hits its Peak RPM. Then I back the HS needle out about 200-300rpm from this Max rpm peak. Its very important to move the HS needle slowly and a click at a time. It may take 5-10 secs for the new needle setting to have a full effect on the engine.

Normal HS settings will be very dependent on local conditions and fuel choices. Also it will depend on how new the engine is as well and how its broken in and so on.

Normal for the 160 on the Cool power 30% heli and a 17-12 is about 8100-8200rpm, with HS speed needle around 1.5 turns open. Now if you are lower elevation then the HS will be richer setting, Higher elevation the HS will be leaner setting.

It also is dependent on temperature and whether or not you are running velocity stacks or restrictors or not. All these things will affect the top end rpm.

I don't have any experience with the Powermaster to know its comparison on top end power with the Cool Power 30% heli. But I would assume its close. You might be a just a little rich on the HS needle, but that is only up to you. I can't set it via the Internet.

Troy Newman
Team YS

apereira

Thanks for the advises.

Regards