YS 63 vs OS 91

Which engine would you think would fly a .60 model the fastest:
YS 63 running 30% fuel with a 12x8 Prop
OS 91 Surpass running 10% omega with a 13x8 prop
joel
Reply to
Joel
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The OS should turn that prop greater than 9500 easily. Don't know the RPM of the YS. Assuming it is about the same then the speed will be about the same too. The pulling power of the 13" prop vs the 12" prop will be considerably greater. I like the biggest diameter prop that will fit the plane, 6" - 8" pitch at 9500 - 10k RPM is fast enough for me. I like the price of 10% fuel better than 30% too. Not really endorsing either engine. The OS 91 I have ran great right out of the box. Very easy engine to operate and the fuel economy is excellent.
Charlie
Reply to
Charlie
If he's looking for speed he should reduce the diameter of the prop and increase the pitch. The bigger diameter will give him pulling power but it will also act as a giant air brake.
Reply to
Normen Strobel
Depends on the plane. If it is a 60 size WW I bipe, the OS may fly it faster due to the larger prop diameter. If it is a slick sport plane, the YS will rule because it will be turning the prop a good 1-2000 RPM faster at speed.
Reply to
Paul McIntosh
if you are attempting to correct me, you would have done better to to provide some rpm data for the ys engine turning the prop he asked about ch
> If he's looking for speed he should reduce the diameter of the prop and > increase the pitch. The bigger diameter will give him pulling power but it > will also act as a giant air brake. > > -- > Normen Strobel > snipped-for-privacy@zoominternet.nospam.net > >
> > The OS should turn that prop greater than 9500 easily. > > Don't know the RPM of the YS. > > Assuming it is about the same then the speed will be about the same too. > > The pulling power of the 13" prop vs the 12" prop will be considerably > > greater. > > I like the biggest diameter prop that will fit the plane, 6" - 8" pitch at > > 9500 - 10k RPM is fast enough for me. > > I like the price of 10% fuel better than 30% too. > > Not really endorsing either engine. > > The OS 91 I have ran great right out of the box. > > Very easy engine to operate and the fuel economy is excellent. > > > > Charlie > > > >
> > > Which engine would you think would fly a .60 model the fastest: > > > > > > YS 63 running 30% fuel with a 12x8 Prop > > > OS 91 Surpass running 10% omega with a 13x8 prop > > > > > > > > > > > > joel > > > > > > > > >
Reply to
Charlie

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