It was intolerable no one was doing anything with their Epochs, and all I seemed to here was “there aren’t any upgrades” which is completely unfair, since there are a variety of tires springs and such easily available, but more than that there is a whole world out there. Sure the Epoch indoor racer doesn’t really need upgrading but I decided mine needed a LiPo battery for a little more run time and that was the start.
I had decided on a Kokam 145 mAh LiPo but then went ahead and added 2 in parallel for 290 mAh. I also added 2 LEDs and a zeiner diode for a cutoff of exactly 3 volts, it actually works quite well when the lights go out it’s time to charge, and with the 290 mAh pack loosing a minute to the diodes is not really a problem.
After I had finished my first LiPo upgrade I was asked about a Turbo for an Epoch and shown a German website where they were bypassing the motor driver IC and putting external FETs on their cars. My linguistic skills being woefully deficient I was unable to decipher what was being said or more to the point if it was really worth the effort, but the diagrams and photos where enough so I decided to build one and see for myself. (Thanks to Microsash who I believe is the turbos creator) The answer was yes it seemed to have about the same effect as adding the LiPo cells, but combined with the LiPo’s didn’t add that much. After my first try I did like it enough to make some circuit boars and add a 2x2 stack to reduce the on-state resistance which gave me a little more speed, not much but noticeable.
Once I had the turbo it just had to have a modified motor, after all isn’t that what a turbo is really for. And this is where the world opens up for your Epoch, did you know that your epoch motor is just a slot car motor? Nothing more nothing less, the only problem is that it is a good slot car motor not the bottom of the line budget motor, and slot cars run off of higher voltages, up to 20 volts and 4 amps at pro tracks. The specks and data for them will not relate to 3.6 volt operation, but the only physical difference aside from armature shaft length and such is that the magnets are very strong even on the Epoch motor just look at their size compared to the rotor so adding neo’s is out I tried, it’s not pretty, and you really don’t need that much more torque in an epoch motor anyway. But ball bearings, balanced armatures, silver brushes, end caps with gold contacts, and lighter aluminum straps are available the only problem is finding which ones fit. Poly, ceramic and neo magnets are also available but for a more efficient Epoch what we really need is weaker magnets not stronger.
The Spud is named after it’s motor with its aluminum strap, ball bearings, ceramic magnets, silver brushes on gold plated contacts, the armature is wound with 34-gage hi-temp wire, with a diamond-trued comm, and a precision balance job. Hot! Just to see if the turbo was necessary I put it in an unmodified car and yep, the car moved very slowly then smoked. The good news is that since the external FETs bypass the toasted motor driver IC it is now working with a Turbo mod.
No-load motor speed (in rpm’s) and current at 3.8 volts supplied from each car.
Note: Without the turbo your stock ESC will not run a motor like Spud, installed with a load the current will go up and your ESC will die.
For the above tests power was supplied to the motor buy disconnecting the motor wires from the 2x2 Turbo/LiPo Epoch and a completely stock Epoch with the 3 cell battery charged using a LRP Comp. Pro charger then connecting each motor with a set of test leads while taking the readings. A multimeter was hooked in series for current and a Team Orion MPM was used to read the RPM. For consistency the same transmitter and crystals were used for each car. The readings were taken at full forward power. As chance would have it the voltage reading without the motor by both cars was 3.8 volts.
Linear Mode
