Hionimi

Wasn't that the MTB group or something?

This one? (Links to Youtube.)

Edit: I actually noticed another engine in the post jwasko made, in the guide by rhino-aus, the NSR 3005 Shark, crazy specs that one has! My only concern is with engines that reach such a high RPM (40,000), do get that torque of 210g/cm over a wide range or only at that RPM? If the latter is true, wouldn't an engine achieving 30K-35K RPM and 210g/cm torque be better suited than one that does 210g/cm torque at 40K RPM?

Lastly, these airing holes, they're there to cool the engine, but they're likely covered by the flywheel case, wouldn't this give issues like melting or at least warping the plastic?

Edit 2: Checked some videos on the NSR Sharks in a Rapidstrike... Those things are scary at 11.1v... Think I'll stick with 2S1P, found a nice pack (links to Hobbyking) too that can be fitted inside the Stryfe's original battery compartment with some modding, it's almost 1,000A and delivers 25C, 50C in bursts, so moooore than enough.

If you want to go another route, these motors on eBay are well tested and reviewed by the community, in the absence of the out-of-stock Falcon 130 motor. They will net better durability and performance than a Tamiya in most cases; these will need a 2S Lipo, but will also work fine on IMR cell batteries, unlike high-end Tamiyas.

You could also try buying Blade 180s or Extreme Pro 180s but those are about $10 per motor currently. They are regarded by many as just about the best motors ever with 32,000RPM and 42mN-m of torque at 7.4volts. They eat up about 3.8amps (just spinning at max speed).

When planning a power source/battery, note that any motor will draw a lot more current when the motors are stalled. For instance, the aforementioned 180s go up to 22amps!

IMR's and Ultrafires aren't easily available where I live, but I also prefer to use Li-Po's. I know they can deliver seeing as I also worked with model airplanes and multirotors. (I actually wish I could use Brushless outrunners but that appears to be really tricky, but I read you could use their bell as flywheel though!) And 42mN-m for 180!? That's quite a different story! 180 Are more powerful, though again, I hope to stick with engines that fit inside the blaster without needing to saw into the shell. I'm still curious what the torque specs are on these motors MAV13 linked or the 130 Falcon's.

Also, reason why I picked that one Tamiya is that it actually states it has Carbon brushes, picked up somewhere that Metal brushes are generally not a good pick, that correct?