Brent, are you using the accessory output on the CW-80? If so, the ACC Output is adjustable, and may not be adjusted to a high enough voltage for the effect you want.
To adjust the ACC voltage on a CW-80, turn the throttle all the way off, push all three buttons( Direction, Whistle and Bell) AT THE SAME TIME, while holding all three butons depressed set the throttle handle to the setting that gives the effect(Voltage) that you want, leave the throttle in that position, then release all three buttons, then return your throttle handle to off. The CW will hold that ACC setting, and then return to normal operation when you move the throttle handle again.
If using the track power outputs, I can't imagine the CW-80 not putting out enough voltage. Are you sure it is a CW-80, and not a Power-Max 30 watt, or Power-Max Plus 40 watt transformer?, I would still think that those should handle that accessory, unless there were other items being powered from them as well. The Power-Max and PM Plus look almost identical to the CW-80, but the cases are a little shorter in height, and they only have one set of power outputs(track) and no ACC Output connections.
Doug