Engine ID please

[Mike Haverly]

I thought I knew most of the Fox engines, at least by size.  What is this?

[Dennis Adamisin]

Hi Mike
That's the Fox 40 designed by George Aldrich.  Vintage about 1970 give or take. Dad put one in an old "beater" airplane to try.  It ran quite well for the vintage, but they never caught on because they are so large compared to the 35/40's of the era.  One really neat feature was the large mounting lugs with the very broad spacing to help distribute the mounting pressure over a much larger area of the mounts.

AMA museum also has a 45 of the same type with anodized cylinder fins.  I never saw one of those except in the museum.

[Mike Haverly]

I kinda thought that was it but with no markings.  It dwarfs a 36X.  I didn't weigh it but it feels heavy.  It is bulky for sure.

Edit: added photo

[RandySmith]

I kinda thought that was it but with no markings.  It dwarfs a 36X.  I didn't weigh it but it feels heavy.  It is bulky for sure.

Edit: added photo

I have a couple of those , one  new, A friend used one to power  his  Chipmonk  Stunter, it ran very well  and  pulled  the plane with ease, I think a  11 x 6 prop  was used

Randy

[Randy Cuberly]

I had one of those many years ago in a T-Bird II.  A bit heavy but a very solid running engine.  11-6 prop!

A really great 2-4 with a soft break!

I still have it somewhere! 

Randy Cuberly

[Andre Ming]

George designed it?

Interesting.

My first stint at Fox Mfg (hired Aug 1970 as I recall), Duke was still working on getting that engine finished and into production. Duke was still in the process of developing the Schnuerle-type porting. There were raw case, backplate, etc, castings in barrels as well as other raw machined parts. Never a word was mentioned about George designing it.

I do recall an ingenious improvised method Duke created to watch the flow of the incoming fuel/air mixture. A back plate was drilled and fitted with a nozzle. A 3' piece of neoprene tubing was attached to it. On the free end, was a fitting that one could insert the filter end of a cigarette. The cigarette would be lit, and he would stick the cigarette into his mouth and blow. The incoming smoke would be directed by the porting and thus the porting could be fine-tuned to more efficiently fill the cylinder as well as fill the compression area.

After seeing Duke use his "flow-a-nator", I made my own and begin to use it to make mods to the X series of combat engines. Pretty ingenious idea, I always thought.

Andre

[Brett Buck]

I thought I knew most of the Fox engines, at least by size.  What is this?

   Fox 40 large-case. This engine usually runs pretty well but is not very powerful, maybe no more than a Fox 35, but doesn't have quite as much issue with an 11-6. It's also huge.

      Brett

[Andre Ming]

Careful there Motorman... the Fox nay-sayers are always at ready. Can't be TOO complimentary of Fox engines or mayhem results. 

 

 

Andre

[Bill Mohrbacher]

Here are pictures of the 40 40 stunt (or RC) porting with the piston at TDC and BDC.  Also the crankcase innards.  The engine has an aluminum cooling Muff around a steel cylinder.

The color ad shows the never produced 40 BBRC and 40Rat Race.  These examples are in the AMA museum.  Note the front BB housing and stiffening ribs that runs from the mount to the housing.  Neither have pistons.

[Bill Mohrbacher]

Bill Ives (The world's greatest Fox collector) got this experimental 40 "Stunt" from a collector who used to visit Fox.  Duke gave him experimental stuff.  Note this engine has the twin BBs and a way modified crank, liner, piston, and head.  The stock piston was flat topped.

[Bill Mohrbacher]

And a while back, I got this guy off da 'bay.  Lots of GMA type engraving on it; not customer names, but dimensions.  It doesn't use a muff, but a drop in steel fin cylinder.  It uses a button insert with a wide squish band and a flat top piston, cut away on the bypass side.  The case is designed with 3 partitions to blow fuel into the intake port at 3 angles.  The "carb" is stricktley a fuel shut off; it made from a partially machined Fox throttle casting.  The crank is modified.  The is a "2 SPCL." engraved under the exhaust stack; all the engraving looks to be in George's hand.  I am calling it an experimental GMA Pylon Racing engine.  If you know what it is, please share it with us!

For a long while and still we have been thinking GMA designed the 40 stunt.  But I have an Email from the Kiwi who knew George and he has a different story.  Duke had the basic engine designed and sent George a batch of parts to see what he could do with them.  George built racing engines out of them and gave them to Duke.  Duke wasn't happy as he had decided this would be a Stunt and an RC engine (must have been after he made the BB protos he never produced).  So it seems the production engines weren't GMA designed at all.  Again if any one knows or recalls any different, please let us know.  Andre? Help?