There are a total of 3 electric motors:
1 x Drum Rotator/Dart Pusher motor
2 x Fly-Wheel motors
As the speed of its motors are voltage dependent, increasing the voltage feed should be able to yield quicker drum magazine rotation and dart pushing, resulting in increased rate-of-fire (RoF).
In addition, the faster spinning of its fly-wheels should also "throw" the foam darts out at a higher velocity, thereby possibly increasing the firing distance.
Here is how i tested it with some simple components:
Step 1: Get the following items from an electrical supply store.
(Nerf Vulcan modders should be familiar with such items by now!)
1 x Battery Holder (holds 8 x AA Batteries)
1 x Battery Holder Snap-on Adapter
2 x Insulated Wire Leads (Red + Black w/ Crocodile Clips)
Step 2: Attach everything together and install the AA Batteries (in this example, i used 8 x 1.5V AA Batteries which provide 12 Volt power in total). Once again, please take note of the Positive (Red) and Negative (Black) wire leads, do not let them short-circuit!
Final Step: Remove the Buzz Bee Tommy 20's battery cover and clip the Red and Black wire leads onto the connection points (clip properly and note the wire lead colours!).
Okay, time to test it out!
Here are the Test Fire Videos of my stock vs. upgraded Buzz Bee Tommy 20s:
Buzz Bee Tommy 20 RoF - Stock 4.5 Volt Power
Buzz Bee Tommy 20 RoF - Upgraded 12 Volt Power
The stock unit had a RoF of approx. 2 rounds per second, while the upgrade unit generated a RoF of approx. 3 rounds per second. Therefore there was a 50% increase in RoF.
In the upgraded unit, the foam darts also got "thrown" out of the 2 fly-wheels at a higher velocity too, with an average increased firing distance of around 6-7 feet.
If you are confident, you can try increasing the voltage further to increase the RoF and range even more, or use other power sources such as rechargable RC car li-po batteries to do the upgrade.
Just be careful not to burn out your blaster's motors! :)
An additional note for those of you looking to get into more detail in the modding of the new Tommy 20:
The front 2 motors powering the fly-wheels are seperated from the main body unit by a pair of electrical contacts (you can see them when you flip up the front barrel unit), therefore with additional mods, it is possible to power the drum magazine/dart pusher motor and the fly-wheel motors seperately with different power sources and voltages.
Hope we can see more mods done on the new Tommy 20! :)