Fox 35 vs McCoy 35

I have heard lots of talk about the Fox 35 engine but nothing about the McCoy 35 engine. Why?

Advantages and disadvantages?

Pros and cons?

Good or bad?

Fox advantages:

1. Still produced; easier parts availability (although Redhead parts are no problem).

2. Better wear characteristics.

3. The Ultimate 4-2-4 Run (although Redhead is very, very close, or equivalent)

4. Better fits, finishes.

5. Monobloc construction best in the long run

6. Aesthetically, wear and tear ages the Fox in a more graceful manner. Some will say the Fox can't get much uglier.

7. Later ones will take factory, bolt on mufflers (if you are a strap on tonque fan, this doesn't matter).

McCoy advantages:

1. MUCH better nva.

2. Slightly better fuel economy.

3. There's a .40 version. Note that I twisted your original question a little.

4. Sleeve location relative to piston only fits in one spot. On the Fox, you have to be careful to retain the alignment. Helpful when reassembling.

5. Maybe, just maybe, if you took a 2 Sigma Fox and pitted it vs an equal McCoy, the McCoy would have a smidgen more power.

6. Advantage when new: $5.95 vs much more for Fox.

7. Aluminum filings routinely found in 50s/60s era Fox cases at no extra charge (Ft Smith has fixed this for some time now).

8. The Underdog. Like rooting for the Cubs.

9. People will give you McCoy parts. Kind of like Cox reed valve stuff. Folks are more anal about their Fox stuff.

Your choice:

1. Looks...a case (no pun) can be made for both...

All above IMHO, of course.

And I'll think of more...

Currell (two dozen Stunts, maybe 10 or 12 Red and Blue Heads)

A few other McCoy advantages:
1. When mounted in a profile, they don't sputter in the outside loops like a Fox.
2. If you have a Lightning Bar Red Head, you can put the ring, piston, wrist pin, connecting rod and head from a Series 21 McCoy in the RHLB and you have a good durable, powerful engine that doesn't sputter in outsides.
3. When a stock engine wears out, you can get another at a swap meet cheap.
4. I have even taken several piston/cyl assy's and swaped them around until I found a pair that had compression!
Red Head McCoy's forever!

LAST EDITED ON Dec-03-03 AT 02:41 PM (CST)
 
Gary,

In the 50's the Fox was THE stunt engine. It ran in the 4-2-4 fashion we've all come to know and love. It has some problems and quality control was one of them, but when you got a sweet one it was just that. The McCoys of the time were not the Red Heads but the Super Stunts, I've also heard of people using the Sportsman but it was a rear rotary valve engine. General belief is that compared to the Foxes they were down on power although I've heard arguements to the contrary. I think the Foxes were also lighter then the McCoys of the era. Later in the late 50's came the Red Head McCoys amd they too had quality problems, unfortunately to a greater degree then the Fox. Interestingly George Aldrich told me he thought the McCoy by design was the better stunt engine but that the poor manufacturing put it out of the running as a viable stunt motor. Still, when you get a good one it is good. I have a 2 .29s and a .35 that are very nice runners and have been for a long time. The bad fits made for some engines, that I'm told, wouldn't even run though I never had one that wouldn't. Never-the-less, some had very short service lives before the compression degraded to a point where they wouldn't produce allot of power. One seeming acception to the overall poor series was the .40 which enjoyed use by some prominent stunt flyers. When found the fetch a good price. Clean ones at the Toledo Week Signals swap were going for $100 minimum wirh their .29 & .35 couterparts were $20-$30.

I've used both and like both. The McCoys seem to me to be a little easier starting, but I've heard bad words from others trying to make a warm one go. But too, the Foxes give me a hard time warm starting.

That's all I can say about it. I'm sure Kiwi and Currell can held put meat on the bones and srtaighten out any errors I've made.

I see Currell got here while I was typing.

No, I pretty much agree with you, Randy. I forgot that Fox had a little weight advantage vs Redheads.

Value wise, from a NIB collector standpoint, both do pretty well, with a nod to the earliest 2 bolt backplate "Sandcast" Foxes. I think I have seen them around $150 or so. Still, though, a NIB or NIP Redhead .35 can be in three digits. And the .40, Blue Head, Redhead, Lightning Bolt, etc will bring $125 or more, as you say.

Foxes and Redheads both are alike when it comes to oil %. You want 25% minimum, majority castor.

Some nitpicks and minutia...

That little plastic plug that you put in the McCoy conrod is easy to lose.

Nothing is prettier than a new Testor's Gold plug (McCoy).

McCoy didn't make a Gold Case version, unless someone at the factory dropped one in a plating vat by mistake. Fox did, and on purpose, even. I have one, but can't bring myself to run it.

The first gen McCoy 40s (shiny case, no bolt) did something dumb re the lug holes. The front ones were open, like the letter "C". So they broke. The Bolt ones were contained ovals, like a little racetrack, and they were really useful.

People used to look down their noses at you if you showed up at The Old Flying Field with a McCoy Redhead. Kind of like being spotted at Wal Mart. Or a thrift store (hey, we're here to buy muslin for hinges...).

I don't think the Redheads shake quite as bad as Fox Stunts. That's like saying they were like Don Knotts on a very good day...

Color code your motor to your paint job! Try doing that with a Fox Stunt (Fox Rocket 35 Redhead excepted; thought you were going to catch me on that, right, Kiwi)? $150 50th Anniv ones too...

Starting...a wash. Good ones are First Flippers, both brands. Both hot, even. Shot ones never will, but we hardly can blame Fox and McCoy for that.

Thing that is good about both...If you don't like the one you have, just grab another...

John: I think a sideways mounted Redhead still has a little of the Dreaded Fox Disease. Maybe not as bad, true...

Not that I noticed, in fact, it was quite a surprise till I remembered reading that they didn't burp. I like to show that off to the guys at the field. Blubbury rich so that the lines go slack in a loop while you're flying lazy eights with my McCoy powered Shoestring, not a hint of burp. Fox, I love it, Burp, silence, blap blap blap blap, off she goes again. Lotsa fun.

Still, it's nice noing that a brand new P/C assy, or any part for that matter, is just a phone call away. Too bad they both don't exist. Then again, you can always buy a modern engine. Just no romance when the engine doesn't shut off at interesting positions.

I don't remember ever having one of the Mc's burp. Maybe the Fox burp was so bad I miss it when the Mc does. If its that slight, to me it isn't there at all.

My McCoys burp on profile mounts. I've learned to open the turns up a bit and the burp pretty much goes away...same for the Fox. Like already posted, I also give McCoys a slight power edge and smoother run over the Fox. I'm a late bloomer with McCoys but the more I fly them the better I like them. Fox Stunts are still at the top between the two...I learned to fly on one and they are like an old family friend.