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Engine basics => Engine set up tips => Topic started by: Guilherme Souza on June 04, 2018, 03:32:57 AM

Title: Fox 50
Post by: Guilherme Souza on June 04, 2018, 03:32:57 AM

Dear ALL

Is possible to use the FOX 50 in stunt mode?

What is the Venturi design?
Somebody hás the drawing?

Thank you a Lot (https://uploads.tapatalk-cdn.com/20180604/b5acc7053b986c6db0a8468f0149169c.jpg)(https://uploads.tapatalk-cdn.com/20180604/2608efb80d50ea09e77bb523e3b3b421.jpg)(https://uploads.tapatalk-cdn.com/20180604/9d737a3f27c91cfaae8a8e56b632c725.jpg)(https://uploads.tapatalk-cdn.com/20180604/5edc9c9fe0ec619ad6158f6befa4974d.jpg)

Enviado de meu Moto Z (2) usando o Tapatalk

Title: Re: Fox 50
Post by: GERALD WIMMER on June 04, 2018, 05:43:33 PM

Hello Guilherme
I presumed the Fox 50 would be a good stunt motor so have bought one to try off Ebay but I've not put it on  a model yet.
It is based on the 40 heavy weight C frame case, you get more displacement but it is still heavy compared to other modern 50-56 size engines and has a wide spacing on the crankcase . They had a reputation for pre-ignition problems when used as a R/C engine and the head had its chamber redesigned a few times to help solve this tendency.
I believe Fox only made one size (8mm) control line venturi that was shared with 40-74 size engines with the bolt on flange intake which normally means a custom set up is needed (7mm may be a better start). There were some Fox engines with a Perry carb adapter and this would be easier to work with when setting up a control line venturi.
Regards Gerald

Title: Re: Fox 50
Post by: frank mccune on June 06, 2018, 08:18:04 AM

      Hi:

      I have one of these on .45 that is in RC trim.  It was new when I got it and thus far. I have only bench tested the engine.  It was the first engine to pull my test stand over! Lots of power and easy starting.  I did replace the bearing as the original bearings were hopelessly stuck from old storage oil.  It was a freebee so I did not feel that new bearings were problem.

     Can somebody suggest a method of converting this to CL other than wiring the throttle open?


                                                                                                                                           Be well,

                                                                                                                                           Frank McCune

     

Title: Re: Fox 50
Post by: GERALD WIMMER on June 06, 2018, 03:30:27 PM

Quote from: frank mccune on June 06, 2018, 08:18:04 AM

     Can somebody suggest a method of converting this to CL other than wiring the throttle open?

   

Hello Frank
I have flown many a large Fox engines with its RC carb set open and must say they are often better then the Fox venturi as supplied .
Don't think MECOA has any C/L venturi's left but you may want to contact them to verify this.
Seems the best set up will involve some metal work making a flange and welding on a tube adapter for a separate venturi or search E bay for second hand .
If you like playing with JB weld you can get very creative here too. (I may post a separate post on this topic)
Regards Gerald  #^ #^ #^

Title: Re: Fox 50
Post by: Chris Wilson on July 02, 2018, 03:34:18 AM

Quote from: frank mccune on June 06, 2018, 08:18:04 AM

 

     Can somebody suggest a method of converting this to CL other than wiring the throttle wide open?
   

3D printer, perfect candidate for it