RICRAC

I have a Os 160 FX in my greatplanes ultimate 160, and i run a menz 18X8 at 7700 rpm.
But i want more vertical performance, so i tested a menz 20X6 and only got 7100rpm,
and i think that is to low rpm? Will i overload the engine?

Anyone know what the best rpm is for this engine?

Cyclic Hardover

My Feedback: (3)

To much prop. Your going the wrong direction, Go down. I suggest a 17 The manual has two prop sections "aerobatic and sport". If your looking for vertical and 3d stuff, need lot less pitch.

BankYank

My Feedback: (63)

I mostly run APC props so the info might not apply but could help.
I have found for speed a 18X10 works good. For thrust an 18X6 and a good all around prop is an 18X8 All APC.
Pat

RICRAC

How is the rpms on those props?
What i have seen the APCs turn higher rpms on the same size as menz and other, like if i would put a APC 18X8 on it i will get higher rpms than with my menz?

Will a APC 18X8 have more thrust then my menz 18X8?

pe reivers

rpm's mean nothing.
APC runs higher rpm at disappointing performances. Get a decent wider blade prop if you want pulling power, and test it not by rpm, but by plane performance.

RICRAC

Yes im with you on that, That was why i would go to a bigger prop.
Any ideas of what prop i should try?
Os says 3.7 hp at 9000rpms
And i get 7900 peakrpms on the menz 18X8 and 7300 peakrpms on 20X6 menz
What would be the best static rpm on ground?

pe reivers

The prop that stays below 8000 rpm will be best. When it unwinds, it should stay just shy of the max power rpm limit, which BTW is pretty much defined by the muffler you use. Paper values are just that. They work, if you are running the same setup.

flipstart

Go to the tach forum and do a search for OS 1.60FX-there are pages and pages of various planes, props, rpms, and etc.

RICRAC

Ok thanks, i will try to fly with the 20X6 and see how the plane and engine performance will be.

alan0899

G'day Mate,
I run 16x10 or 17x10 APC's on my Katana, you need more pitch not more diameter.
Try it you'll like it. Forget RPM's just fly the plane.

RICRAC

I forgot to mention that it is the greatplanes ultimate 160, so i dont want more speed just more thrust.

Cyclic Hardover

My Feedback: (3)

I'm with this guy.

Tailwheel Pilot

My Feedback: (2)

I run a 18x6 W on my old Giles and it works great.