Fox .15 BB. MA 7-5" MA GF3 prop, 10% nitro, no muffler, 16,000 rpm, I thought the head was way off with the domed head and .040" head clearance, so I thought I shold give the head a skim, but there wasn't enough meat on it, so Itook an old crusty burnt out Rossi insert plug and machined it for a turbo plug and took off another .028" from that to give around .016" clearance or something like that. It went 17,700 rpm that way. Pretty good for a steel piston . Kind of a boat anchor but not as bad as Ithought. (I remembered my old slant plug .15 from years ago)

aspeed, do you really own all those .15 size engines? You must do some combat huh?

I have a few combat planes just to scare me a bit, but don't compete.  I like the control line speed planes, but have nowhere to play with them.  Most motors are for RC stuff, Sig Scamp, Wonder.  I think .15's are a nice size, You can use full size servos, and they cut through the wind ok and go as fast as virtually anything else.

You are having way too much fun!

Maybe next winter I can check the .049's. I have to find a paved field somewhere for the real fun.

I don't remember running a prop smaller than a 7x6 prop on my Fox .15's. Usually it is a 8x4 prop most of the time or a 8x3 for combat. I have a Fox .15BB engine on my mini-Sportster plane, and it is running too good with a 7x6 prop on that plane. So i wind up flying it around 1/2 throttle or so. For combat, If I remember right, I had to richen up the engine a little so it didn't rev higher than the max RPMs they allowed at the time using a 8x3 prop. But it has been a while since I flew RC combat though. I was getting around 14,000 plus RPMs using a Fox .15 BBRC engine.

I test ran a Magnum 15XL engine a while back with a 8x4 prop, sans muffler too, and it was running about equal and maybe arguably slighty better than the Fox .15BBRC engine. But not much difference at the time. I haven't tried a Magnum .15 XLS engine yet.

I seemed to have misplaced most of my Fox .15 videos, except for this one of a Fox .15 bushing engine using a 8x4 prop. The Glo-Bee tachometer didn't like working in the shade too much, but it looks like it was turning around 12,300 RPMs sans muffler with the 8x4 prop on it and 5% nitro-glow fuel. The muffler wouldn't fit on the engine while on the test stand. What was surprising was how well the engine idled like that without a muffler.

http://www.youtube.com/watch?v=CVehnv0uBfg

If you could have just one .15, which one would it be? The Magnum?

Thanks,

Ernie

The OS CVA 15 (expensive) and the New magnum 15 are the strongest stock engines. The OS has a very very good carb on it. this one should be on ever 15.

The LA 15 is good also but need a little work to it and become a strong engine also.

The Norvel is the strongest, in my opinion, it is also the lightest.

The stock RC carb gives an excellent idle (down to 2500) but limits the high end too. Replace it with an MVVS .15 carb (a direct drop-in) and it will easily out-rev the Magnum .XLS (blue head) engine.

The MVVS .15 looks to be a really strong running engine. I have a couple of them, but I haven't run them yet to be sure.
Although the Norvel looks good too. But the Fox .15 makes for a great sport engine though. All of these engines are easy to get parts for too.
If your budget is tight, you can trade in a clunker engine to Fox and get the Fox .15 engine at 1/2 off the list price too. That does tend to make it most attractive then.

I guess the Norvel is ok if you get a bigger carb, but if you are going to change it from stock, the Fora with an rc carb would be wicked.  The Magnum XLS is about the best bang for the buck, and I still like the OS LA for piddly planes but would only buy a used one in good shape because they are way overpriced for what they are.  The LA is actually pretty good considering it is a plain bearing non scheurle motor.

Do they still make Norvels? Where's the Fora from?

I got my Fora from Yaroslav Melnikov <font face="Arial">http://aerohobby.ca/store/</font>  I hope it is ok to put that here.I think Hobby Club has them too. They are scary fast especially when you put the 6.2"-5" pitch toothpick props on.  I think Norvel has started up again after a short absence.  It is called something else like N/V  I don't know, someone else will likely say.  I got most of mine at swap meets.  I like them all.  .049's .06, .074's and .15's.  I don't have any bigger ones.  The Taipan is pretty good too, I remember racing against them  in the 1970's, and saw one at a swap meet and had to try it out for $20.  I don't think they are made anymore.

Interesting aspeed, thanks!