Time for PolyMaxx to go 24v brushless!

Hey everyone! I figure with my new polys configured for 24v at 4.4 amps (6s) it's time to convert the "PolyMaxx" to brushless!

I've been looking around and found it hard to find high voltage brushless systems...but I think I found a good esc/motor pair - a Warrior 9920 and Lehner XL 1600 motor.

Before I plop down $350, does anyone see a problem? Any performance estimates? I'm well versed in the brushed world but not so in brushless...so I need some guidance. thx!

[RC-Monster Mike]

First things first, Welcome to the forums! this very setup has been discussed on these boards at one point. I think the setup will be excellent. I run the xl2400 on 18.5v lipo(5s) and it works excellent(I actually dial almost half of the available power out for racing). I will probably go to the xl2000 on my setup to keep the power more manageable. I think the 1600 on 6s Lipo would be an excellent setup, offering nice runtime as well as incredible power. as far as a performance stimate, I guess I will simply say it will be incredible. I have run the xl2400 on 6s lipo once or twice and it is absoluttely rediculous for anything but a speed run! The 1600 should be more driveable, while still offering outstanding performance and runtime.

Thanks for the quick reply Mike! I tried searching but got no results :-( What gearing would you recommend for topping out at ~35 mph?

[RC-Monster Mike]

19/66 with stock diff ratio and stock size tires will get you a little over 35 with a fresh charge and about 35 through the whole run. Stock gearing will get you around 35 with a fresh charge and around 33 or so throughout the run. The torque will be out of this world, and the runtime will be very good as well. I typically gear my trucks for around 35mph for racing as well.

[maxxdude1234]

Sounds good fastMHZ, I've seen some vid's of your set up before. I run a 2000XL at 21.6v and speeds are incredible, but runtimes are even morfe incredible. With plently of slow driving, fast driving and speed runs I get almost 40 minutes of runtimes. With the 1600XL on 4.4Ah lipos, unless you are constanly driving fast or racing I would expect almost an hour of runtime!!!!!

[Serum]

What lipolys are you using? How much C can they deliver?


is it a 2p6s configuration or a 4400 6s? That motor is nice and mild to the esc, so i would not expect any problem from it. I saw you have got a audible 6S alarm, is it adjustable with jumpers?

Thanks for the tips and comments so far! To answer your questions:



What lipolys are you using?
is it a 2p6s configuration or a 4400 6s?

2x PolyQuest 11.1v 4400mah wired in series...so 6s...and it's a true 6s. I found inside my previous e-tec 3s packs that they were really 2p3s...and you can't tell unless you take apart a cell as seen in this pic:



In the pic you see one cell unwrapped and the second cell to the left. So my previous setup was something like 2p(6s2p), amazing it ever worked and charged properly like that.



How much C can they deliver?

12c...and with ~22.2v (> 24v fully charged) * 4.4a * 12c = ~1267 watts continuous...it's 16c burst for 10 seconds



I saw you have got a audible 6S alarm, is it adjustable with jumpers?

It's entirely automatic (www.battsignal.com). Upon powerup, it counts the cells and remembers the count. Then it beeps and flashes based on the discharge on that cell count.

[Serum]

With 1300 watts and a lightweight maxx, you can make it fly! and you will have got endless runtime.. (well.. Near endless...)

Nice little device that is!

I felt well informed enough now and just placed my order! I can't wait.

Mike - I didn't see any shipping method specified during checkout...Please don't use USPS Parcel Post as it takes a month to get here and they lose things all the time.

[RC-Monster Mike]

I use USPS Priority, so you should get your stuff by Wednesday!

Over on the Traxxas forum someone said I should have gotten a Feigao XL motor instead of the Lehner XL I got due to the larger can and heat dissipation. Am I going to have a heat problem with the 1600XL on 24v?

[RC-Monster Mike]

Run a heatsink and a fan and you won't have any trouble at all. In fact, you will LOVE the setup!

[Serum]

that feigao XL is the largest feigao available, it will drain your batteries much quicker.. if you gear it properly, the motor would barely get warm.