Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

engine size/prop for Patriot...?

Reply

Old 06-23-2004, 07:18 AM
  #1  
John@Squadron55
Junior Member
Thread Starter
 
Join Date: Nov 2002
Location: kitchenerontario, CANADA
Posts: 27
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default engine size/prop for Patriot...?

I'm sure you guys are sick of answering Patriot engine questions, but I'm new to this forum, so here goes...[8D]
I was going to put an OS .61 on the front, but was told it would be tough to balance.
My next choice is the OS .46AX (the new engine)...the figures OS gives look impressive (1.65Hp), but we all know how accurate those can be.
Is there a better engine for the patriot (I can't afford a Jett engine)?
What prop should I use on the .46 for all-out speed (I'm taking off from grass, so I need to get airborne too...)
Thanks,
John
John@Squadron55 is offline  
Reply With Quote
Old 06-23-2004, 09:53 AM
  #2  
bob27s
My Feedback: (19)
 
bob27s's Avatar
 
Join Date: Apr 2002
Location: Cleveland, OH
Posts: 5,576
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: engine size/prop for Patriot...?

The OS 46AX is a pretty nice engine..... but is not aggressively timed, and with the stock muffler you want to keep the engine running up toward 14,500 rpm on the ground.

The engine is not designed for higher RPM.... that is why the OS recommended props which are fairly large, to keep the engine down in the 12,000 to 13,000 rpm range. Setting up for ground peak rpm about 14,500 will let the engine unload to just under 15.5K in the air, which is what you want.

Break in using an APC 9x7 or clipped down 10x6. Let it turn up to 14,500, while still running a tad rich. You will only need about 3 tanks of fuel like that.

Start off flying with either a 10x6 or APC 9x8

You may want to go with a 10x6 for grass operations. Again, watch the peak RPM on the ground. After a handful of runs, the engine should turn the full 10x6 around 14,000 to 14,500 peak RPM. Alway back off of peak about 500-600 rpm before flying.

With some more time on the engine, you may notice the engine running around 15,000.... then you can experiment with 9x9 and 10x8 props to pull it back down to 14.5K.

Adding on a Jett-Stream muffler later on will allow you to turn up closer to 16,000.

Also... if you are budget minded, I have found that the Thunder Tiger .46 has been an outstanding engine, and enjoys having a tuned exhaust installed. My TT46 will outperform my OS46FX with higher RPM props.

Bob
bob27s is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service