What is the diameter of the drive motor in your WTC?
Also, your stated WTC dimensions seem to not be possible. You said, "The WTC is about 18.5mm long and about 37mm wide" The length dimension would appear to be impossible based on the width, which would make your WTC less than an inch long..
What is holding your drive motor in place inside the WTC?
Hahahaha, oops. The diameter is 37mm wide and 185mm long. I'm not great with decimals, and that's the metric system's greatest drawback...yet greatest advantage, but anyhoo...
The motor's diameter is...I don't know. This is the motor I'm using:
http://www.geocities.com/smallworldmode ... otors.html
It's the SWMM-1 (300-sized motor). I assume it has the same dimensions of a S300 motor. I have yet to run the sub at 100% throttle, so I can't say if using this specialized motor is ideal or not. It's replacing a Mabuchi motor like the one:
I assume it will be an improvement, if not in performance, at least in efficiency.
The drive motor is being held by friction. I glued plastic tabs to the motor directly. I slid the motor into the "rails" glued to the inside of the WTC. I then glued a few pieces of plastic in the "rails" so the motor can't slide back and hit the servo/electronics tray (probably wasn't necessary, but just in case). The motor can't slide forward since the fuel tubing adapter would hit the 1/8" oilite bushing and shaft seal. Here's a close up: