???12th Scale 4-cell Stock Motor Tuning???

[Sean Patterson]

Does anyone have any recommendations for 12th scale 4-cell motor tuning? Currently I'm running an Epic ROAR Pro-Stock with Trinity #4505 brushes and Trinity Blue springs, which are the lightest springs they make. I don't have a dyno so its tough for me to say for sure but the motor seemed to rev higher in the stand when I put a green spring on the negative side. Anyone have any recommendations???

[TEM]

Assuming you did everything else right (bushings, shimming, hoods, proper comm cut, etc) Brushes, just go with reedy 767's, if you're a trinity fan go 4499. Short track run full face, long track consider slotting the brush to give it a little more rpm. Springs red on + green on -. Typical stock motor like this draws over 8amps on 3volts noload on a turbo35. You really don't have to use lighter springs thinking it's a 12th scale and doesn't need much power and you worry to make run time; a typical pack of matched 3300's is plenty. If you cant make run time check the battery, gear down, drive smarter...

[stormperson]

With the Epic roar, make sure to gear it correclty, normally down a few teeth from a monster, so on most tracks around a 27,28/100 with like 1.85 tires, just make sure not to overgear it. As far as brushes, 767's, 4499's, f-brushes, or even the XXX brush (although it lacks the power of the other brushes) are all good choices, as are putnam green/blue's. You want to be able to run as light of a spring as possible (without arching), and with that motor two greens normally are pretty dialed, sometiems u can go to a blue negative on a big track.

[TEM]

Stormperson, I'm going to have to disagree with some of the stuff you wrote. Don't you mean gear down a few teeth with the monster stock and not the other way around? If he's running 12 scale (foam tires anyways), maybe suggest rollout in mmpr instead of gearing. I haven't run roar stock for a while but if I remember correctly something around 45-50ish mmpr should be a good starting point. Well, you'll know after a pack or two anyways...

[Sean Patterson]

Right now I am running 45.4 rollout. Most people at my track run 43-48 rollout. its funny though, even though the dyno readout on the Epic reads a lower RPM than the Monster, the EPIC seemed so much faster on the track.