gearing question

[otherguy]

I have a T3 and I am putting in a P2K2 motor in it. What pinion would you suggest that I use with it. Would anywhere from a 16-19 work? It has the spur gear that came with it, which i think is an 87.

[PSteers]

Since the p2k2 is a 24deg. stock motor, you should start with a 20-tooth 48-pitch pinion gear. If your track is short with a lot of turns, try a tooth lower. If the track is long with few turns, try a tooth higher. Don't go up by more than 1 tooth, though, or you might overheat it.

[TyceCCSU@aol.com]

I agree with BIO, start with a 20 tooth pinion, maybe a 19 for a track with few starights or short straights where torque is needed over top end. Be aware of the P2K 2's dyno results in a post in this section. Check them out.

[XXXER]

DANG, I do not know where you guys run, but 20tooth? 19 tooth? These are what I run in my stock BUGGY. I would start out with a 17 tooth, and move up, possibly one tooth, seeing how they do. The type of gearing that you suggested may have worked on an original P2K, where there is more torque, over RPM's, but the P2K-2 has more RPM's than the P2K, well; it basically sits right in between the GM3 and the P2K

-Steve

[TyceCCSU@aol.com]

Hahaha,
A 17 tooth? You've lost your mind XXXER, lol. May be if he threw a modified armature in his P2K 2. Yes your right in stating that the P2K 2 has more rpm, but do you have a dyno to see for yourself? No? Yes? Either way, I've purchased Robotrinics and the #'s are very close with the P2K and the P2k2. The differences are the Efficiency and some greater rpm ratings on the P2K 2. However, the power band on the P2K 2 is slighlty less torque at high end but higher torque at low end. What ever the arguement even the manafature states a 19-20 tooth starting point. Not even on the smallest track I've raced on does anyone use a 17 tooth gearing, NO ONE! Your entitled to your opinion but when manafactures state a staring point you useually don't move more that 2 pinion teeth up or down. If you do, your probably running the wrong motor. Good luck

Grizzbob your opinion??
PS Grizzbob, I'm compiling a whole bunch of data on the P2K 2 from different racers. Baiscly dynoing there motors for free to get some sort of staticial data. 6 Sigma, std. deviations etc etc.

[otherguy]

jeepinator: Someone told me that to many teeth would cause overgeaing and could harm the electronics, but I didn't know how true that was. We have different tracks but one for sure is short straightaways and more turns, they told me that I would probably use a 16 tooth, but I wanted more opinions.

[highroller]

The P2K2 is basically the same as the P2k and GM3, the slight increase in the RPM band doesn't dictate a big change in gear ratio. What does help is increasing the spur size, using the same pinion but going from a 83 to 87 seems to help the lack of torque the P2K2 has. Start with the 87/18 since I don't know your track size or layout. Take note of how the truck accelerates off the turns, how soon it gets up to speed and the motor should not get too hot to touch. A motor that is undergeared can have the same effect as one that is overgeared.

[Grizzbob]

That's true, I've only tested a couple of P2K 2's so far, but the power band of both seem pretty much the same as the MVP(which is what I was kind of expecting & hoping for), so it'd be best to gear it just like an MVP. From what I've seen in my testing, they cna put out the same top end as a normal P2K(around 27,000rpm), or as high as 30,500rpm, with torque & power numbers varying appropriately(the higher rpm motors having less torque & slightly less power, & the lower rpm ones having more overall torque & power). The one difference that I thinkis significant is that the P2K 2's do seem to produce better torque at high rpm(which is a weakness of the P2K), so they shouldn't have as much trouble carrying speed through sweepers like a standard P2K does. Plus, they also seem to stay cool(like I'd expect of an Epic motor), unlike the MVP, which we all know tends to run a bit hot........:cool:

[XXXER]

jeepinator, thanks for defending me.

Tyce, it is all a matter of what we have both found to work better for us. You, are obviously a big motor tuner, and insistant on getting every last bit of performance you can, out of your motor. I have found to gear lower, works better for me, but, then again, it may be my driving style, since stock motors do not come with the torque, that I liek to drive with, may not fit you, or his driving style. Also, tracks are different, my track that I race on, just seems to work better with a lower gear ratio, it is a smaller indoor track, that has all sorts of traction, and some of the best clay around(at one time, it was Brian Kinwalds favorite!), so, again, conditions may play a role in that. With an outdoor, or looser track, you may want to gear a little higher, so as to tone down wheelspin, because you do not yet have a trained throttle finger, and help you aid in that.
Also, going the fastest down the back straight, does not make you win the race, in stock class, the straight accounts for all of 3-4 seconds of your lap time, and when you spend another 15 in the rest of the track, you can get a lot more time off of your laps in other sections of the track. My guess, is he will be racing a beginner class, and if you watch those guysm, they are on and off the throttle constantly(no offense to otherguy), and I think that they would benefit, from more torque, because they, and the people around them, have not quite learned how to carry speed through the corners.

When I post a post, I have usually thought it through thoroughly, lately I just have not really been posting as much, and I rarely go into detail, because I have so many times before, that it does get tiring after a while. Usually, I just hope that people will just take my word for it, and if they have another particular question, by all, ask away!

I will try to give more backing to my posts that I do from now on.

-Steve Bylund

[TyceCCSU@aol.com]

My appologies Steve, I was having one of those days. The problem with half of the posts as you have mentioned is the lack of information people use to support there opinion. In addition to that, people like to take the word of people whom they see as qualified. I like to use the analogy of Nascar drivers, yes the drivers are the best in the industry, but a good percentage don't know jack about setting up a car. Hence the Crew Cheif. I believe that many of the younger guys here tend to follow or copy what Kinwald (for one example) is doing. Truth is, there motors are dynotuned for the selected type of track and who knows what other type of team hlep there getting. In addition, I race near RC Car Action's home tracks and have seen the staff race first hand, many times against them. Truth of the matter is, they are BRILLANT when it comes to technical aspects, but driving!?!? Thats another story, (sorry guys!) Most of them i should say. Which goes to prove my point of a valid techician, I being an Engineer naturally understand the technical aspect, and my driving skills could be improved only by equiptment, and some practice. So yes, you were right in stating i like to get every little bit of power out of my motor. The way I like to look at it is like this; I spend 1000's of dollars on equiptment to spend no more than 20 minuites on the track. Hell, I'll run my motor into the ground if it'll get me into the A-main, not to say I run my motors that way, but have compromised having a motor last an entire year vs performance.

Once again, I appologize and you were the better man for not even taking a stabe at me. :confused: :D

[XXXER]

I could stab you now! but it would all be in good fun. I think, in a way, we are both correct in a way. Like I said earlier, our conditions/tracks are the main variable, that we had to deal with, you are right with yours, and I am right with mine.

-Steve

[highroller]

The way I've found to make the MVP run cooler and just as good as the Epic motors is to narrow the brush (leading and trailing edges). Another thing that help is aligning the brush hoods so that the brush wears down the center. If the brush is misaligned it's not conducting the current properly (sort of like retarded) and the brush is actually behind or ahead on the comm segment. MVP seem to work better with the stock springs or purples (Trinity) with a little more tension on the positive. To see if it works or you need more spring tension press down on the positive brush while doing a dyno pull. Some motors work better if you shave (grind) a little of the brush. Adding a little spring tension will sometimes increase the torque, when using a cut or narrowed brush. You still get a few motors that don't respond to any tuning changes, those may need to be remagnetized or the magnets may not be aligned properly when installed in the can.

[mikedude]

Coombi-ya, Coombi-ya....:o

[otherguy]

what's all the talk about the MVP, can't it be about the P2k2:D