5 cell + mamba 25 in a tenth scale for racing?

I am not saying this will work ,but I'm sure it is not that far of. Novak makes oversize speedos so that resistence is extremely low for that little edge in spec racing classes. Not many 10th scale batts I know of can support 700amps for any length of time. Most of novaks stuff is for 6 round cells, higher voltage setups only reguire a fraction of the amps.

ignoring eficiancey and other small variables brushless motors tend to follow some basic rules.

- more kv = less in.oz./amp torque (per amp)
- more kv in same size motor can handle more amps
- motors reach max eficiency at a voltage that puts them near there rpm limit
- smaller diameter motors can handle more rpm
- small motors and large motors make equal torque per amp if the kv are equal, however the larger motors tend to handle more amps


my MM 5700 makes aprox. .24 in.oz. of torque per amp I average less than 34 amp racing.

the 2700 kv small motor makes .5 in.oz./amp. So less than half the amps are required to make the same amount of torque

I would be running the 2700 on 2.5 times the voltage (6-cell nimh to 5 cell lipo). so the 2700 would be spinning the same rpm as a 6750 rpm motor on 2s = I can gear down a couple more teeth = even less amps required

new systeme would make the car weigh 20% less = 20% less amps needed.

I know this is pushing the limits, gearing for a particular track will be critical, and maybe not even worth it, but it is not that far off. Any constructive criticism is welcome, I am asking for it. Eagle tree graphs of hot 18TH scale cars or race condition 10th scales with a breif description of running conditions would be extremely usefull. Serums #'s for his monster are appriciated; there is a huge difference between the weight of it and my little car, but still worth considering. Shooting me down because Novak rated a speedo at 700 amps is not very constructive.

jhautz thanks for the positive response I'd love to see more info on that xxx4 setup

I'd like to hear more opinions on wether or not higher voltage feels smoother, that is a big part of the reson for wanting this setup. I already have an M.M. running in the car. 2 or 3s M.M. and 400 size motor would be almost as light as 25 (with heat sink, ubec, and equal watt/hr 5s) and really safe and easy.
My only real experience between voltages has been 2s and 3s with a 4100, 6800, 8000 in an 18t. Lower kv motors seem smoother and higher voltage seems crisper. Maybe the 2s bat. was just a little weak for the higher kv or taller gearing, want others opinions.

[jhautz]

Originally Posted by Cheater

jhautz thanks for the positive response I'd love to see more info on that xxx4 setup

Im on the road for work this week. I'll see what i can dig up when I get home this weekend. No gauranties, its been a while, but I. Do remember having a picture and saw it run with my own eyes.

[BP-Revo]

Originally Posted by Cheater

Shooting me down because Novak rated a speedo at 700 amps is not very constructive.

I wasn't "shooting you down," just simply using a sledge hammer. :018: Just kidding lol :005:

I was just agreeing with the post before my (Serum's) that stated 25amps is too little for a 1/10 scale...

I was just pointing out the vastly high amp rating on a popular brand of 1/10 scale speeds controls (even though it is brushed).

However, it seems like you have given this considerable thought and have calculated it down...so I guess it's worth a try. A mamba ESC is only like 80 bucks in the end, so its not exactly a wallet buster, but its not something I would recommend.

I would like to point out one thing. On the CC website, I read somewhere that using the M25 ESC on 3S Lipo with the 8000kv motor voids the warranty...while with the MM it says you are not supposed to use 3S on the 7700kv because the RPM would be too high for the motor, but the ESC is fine. So, I'm not sure you can overtax a M25 like you can a MM...

It seems to me an MM has much more research put into it than the M25, because (supposedly, from what I have heard) the M25 coggs a bit at startup with the 8000kv motor, but the MM doesn't cog at all with any motor...

Well, whether you decide to do it or not, good luck...

*cocks gun...takes aim* lol...couldn't resist...

found something today http://www.megamotorusa.com/
acn 22/10/2E & 22/10/5 both come with mamba-25 for
10th & 12th scale.


here are some more novak #s
- 4300 super sport = 175 watt motor, 225 controler this system wins alot on our tracks. It is not the fastest, but fast enough and easy to drive
-novak has a brushed 1620 amp 6 cell nimh controller (the gtb)