Olympic 15

ebeneezer Wed Aug 21, 2013 11:44 am

Hi all, my Olympic runs great. I am planning to put it into a Kielkraft Firebird controline model. As I know nothing about engines what size prop should I use? I'm currently using an 8x6, the only prop I have. I suspect I probably need an 8x4. With the 8x6 !'m currently running at about 5280 revs on 16% nitro. What should I be getting.

cheers RC Plane

**RknRusty** Wed Aug 21, 2013 2:24 pm

Just trial and error, Eb. Before you know it you'll have a drawer full of props. Sounds like the one you have is a good enough starting point. You just have to find one where you and the engine both find your comfort zone. I have never run a .15, so I'm not the voice of experience on that engine in particular.

crankbndr Wed Aug 21, 2013 3:20 pm

This is a good write up on the engine, looks like its happy in the low teens

http://www.mh-aerotools.de/airfoils/documents/cox_test_olympic_15_aeromodeller_november_1959.pdf

ian1954 Wed Aug 21, 2013 3:21 pm

All the following are within the limits of a .15

7x6, 8x3, 8x4, 8x5, 8x6, 8x7, 9x3

but the recommended starting size is usually 8x4 or 9x3

Jason_WI Wed Aug 21, 2013 6:43 pm

I was getting 15,300 with an APC 8x4 prop and Sig champion 25%. I would check to see if your reed is sealing correctly with that low of an RPM.

Here is a video:

**RknRusty** Wed Aug 21, 2013 8:28 pm

That's a really nice steady engine, Jason. Are you flying it?

Jason_WI Wed Aug 21, 2013 9:32 pm

nope. It's sitting in a plano box.

ebeneezer Fri Aug 23, 2013 10:20 am

Oh dear how silly was I. I had my tacho set on a 4 bladed prop, Now turning 10800 revs, now thats better. Just ordered an 8x4 now I compere with Jason.

Cheers Flying

**Cribbs74** Fri Aug 23, 2013 11:40 am

I have done that before. Welcome to the club!

Sponsored content

Olympic 15

Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15

Re: Olympic 15