Kelly S16C

[brnursebmt]

Monty, I want to build a S16C for a USRA race to be held at our local track. Im told that the hot tip is a Kelly Contender set up with a Kelly (Proslot) S16C armature. My question is what is the difference between the Contender set-up and the set-up used in Kelly's S16C motors? I have seen a car with this combination and it really was much faster than the others with blueprinted Kelly's or other makes. Thanks.

Bobby Robinson

[Monty @ B.O.W.]

Bobby,

I'm only aware of two Kelly setups, and both are used interchangeably with a variety of C can class armatures. The most popular by far is the ultra light. This one is recognizeable by the large round hole in both flat sides. The other, named the ultra fast, is actually slower in most applications. It has small rectangular holes top and bottom. If you've seen something different, its a new one for me.

Super 16C armatures work well in the ultra light setup. I would reccommend magnets slightly weaker than you would use for a Gr.12. For most power supplies, the ProSlot millenium blank will be a bit faster than their Intruder blank. Since these are long armatures with a lot of wire wrapped on them, high timing is a must. Gearing will prove to be similar to x-12, maybe a bit taller. Otherwise, I use the same brushes and springs as I do any C can motor: Champion light springs and Golddust brushes.

[brnursebmt]

What air gap would you suggest?

[Monty @ B.O.W.]

Bobby,

In most cases, I build C can motors with a magnet gap of .533 - .535". There's lots of variables to fiddle with in a motor, but thats one I prefer to leave as a constant. Anything I might gain with a tighter gap can be had with stronger magnets or lower timing - and less risk of rubbing the arm, wasting power moving air, or offending the tech inspector.