Gearing?? - 8ight, Mamba Max, 8XL, 4S

[JeffEmbracedDC]

Hey, guys. So as the title says, I'm converting my 8ight to use a Mamba Max, Feigao 8XL, on 4S.

So far everything is pretty much handled and set. The last question I have is gearing.

With the stock 48t Spur what pinion should I run on this setup? (8xl, MM, 4S)

In my Hyper 7 I ran a 16T pinion on a 46T spur and would get top speeds of approximately 45mph on 12 NiMH cells. I'd like to get the same or slightly better performence on the 4s in the 8ight.

Thanks, guys!

-Jeff

[BrianG]

Start by using the speed calc thingy (link in my sig) and start from there watching temps...

check out the speed calculator and choose gearing based on the speeds you're looking for.

You probably will want a fan on that MM, and probably some additional caps. An 8xl on 4s in an 8ight is going to be a lot for that little controller. Don't be suprised if the stock caps don't handle it for long. I'm not saying it won't work, just be careful ;).

J.

lol, darn. Brian beat me to it! Posted as I was typing.

[JeffEmbracedDC]

Thanks, guys!

Yep, I've ordered a set of 25mm fans and a Novak cap for the battery leads. I plan on leaving the 3 smaller caps alone and seeing what kind of temps I get from there. I plan on mounting a fan on the heat sink and one blowing through the bottom of the case on the fets. Does that sound about right?

Thanks, guys!

-Jeff

Also..

Does this look correct? I have a stock 8ight buggy.


Differential Ratio: 3.3076923076923075
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 48
Pinion Tooth Count: 16
Total Voltage: 14.8
Motor KV: 2084
Tire Diameter (inches): 4.5
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.0073
Spur/Pinion Ratio: 3 : 1
Total Ratio: 9.92308 : 1
Tire Circumference (inches): 14.14 inches (359.08mm)
Total Motor Speed: 30843.2 RPM
Vehicle Speed: 41.61 MPH (66.84km/h)
Effective Speed Rate: 2.81mph/V (4.52kmh/V)
Effective KV Value: 2084
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...

Thanks!

[JeffEmbracedDC]

Also... does this fit the 8ights center diff?

http://www.rc-monster.com/proddetail.php?prod=KYOIF148

Thanks!

[ilpufxit]

I'm running the identical setup. It flies, stays cool, runs a long time. I originally ran an 18t pinion, still worked well but got pretty hot. 14t works awesome and it still has more top end than I could use on a track for sure. I don't need a fan (so far) but it is pretty cold out.

[bdebde]

Originally Posted by JeffEmbracedDC

Also... does this fit the 8ights center diff?

http://www.rc-monster.com/proddetail.php?prod=KYOIF148

Thanks!

Yes, but you may need to sand down the outside of the diff cup a bit.

[stum]

Same setup as mine.. I use 2s2p packs in series... geared 24/68 right now in my erevo with some special cooling.. lol it keeps good temps but with my cooling it stays at 80 even under WOT crazy running :)