Actual activity on the test activity examining the impact of weight and motor upgrades. As originally specified the activity was essentially an Athearn blue box series. For the motor upgrade portion, that is appropriate, but with the weight variations some more recent models are needed. The additional model types are as follows
1- Bowser C636 first release motor
2- Walthers Proto E7A
3- Athearn Genesis GP9
4- Athearn Genesis F9A
5- MTH bi-polar
There are some other potential candidates, but these will cover most of the questions at this point.
The first test adding 154 grams to the Athearn BB GP38-2 was completed and evaluated. As suggested a good draw bar force increase was measured. This was accomplished with a loss in low power performance. The starting voltage increased a few tenths. The starting velocity increased from 3 t 6 SMPH. While these do not sound like much, both performance coefficients went down slightly. It will be interesting to see how this trend changes with additional weight. It is anticipated that the draw bar force increase will diminish and the low-speed debits will grow. The answer will be in the data soon.
