Thanks and New Brushless comments
 

I just wanted to say thanks to all on this forum for the info and inspiration to add brushless to my Emaxx.
I added a Feigao 8XL, MMax ESC, UBEC, tiniest pinion I could buy, and (given what I read here) built up two 5S1P A123 battery packs (complete with copper braid upgrade!).
So it all went together OK- the batts don't sit well on the standard chassis but some zipties helped.
The MM fired up OK even on the voltage from 5S (16.5 or so), as long as I turned on the UBEC and radio first. I thought I'd take it for an uber-gentle trundle as a "proof-of-concept".
Ready
Set
1% on the trigger: a nice smooth start
25% on the trigger: ZING! CRASH! The maxx flipped over in its own wheelbase and smashed a couple of shock towers. Batts spread everywhere. ESC off the velcro. Wiring looms like spaghetti. WOW!
THIS is POWER. I thought it went well on 16 cells/Titans but this is undriveable for me (at least in my yard). I cobbled it back together and couldn't use much more than 15% trigger travel or the damn thing just flips.
I'll fix the towers and get a new chassis, and try it in a big space- what chassis do you think is safe and not too dear?
Thanks again for the inspiration, brushless is Big Fun!

Try FLM extended chassis. I am having the same difficulties with a Neu on 4s. So I am adding some weight, FLM chassis, hybrid bulks, 1/8 diffs, metal cvds and eight SuperMaxx shocks. I am hoping that will help a little.

Duh!! How is that Patrick :)

Do you mean 4s? :whistle: There is two cells in the trackpower packs, so repeat after me (in Barney the dinosaur voice) 2+2 is 4, 2+2 is 4. See now your getting it :great: :rofl:

ICUBoy I recommend the traxxas wheely bar, it makes the car much easier to keep on it's wheels, or at least just the back two :yes:

You are absolutely correct.. brushless is Huge fun... you've chosen a great setup to start with... :gasp:

Thanks for the detail on how to start the MM with this kind of voltage. I got my DeWalt pac Fri nite and have harvested the cells. I'm doing something very similar, but using a 540c 9xl and was trying to decide on what to make, 5S1P was what I wanted to do initially, but was just about to decide to try 4S1P since my charger can handle that. Think I'll stick with 5S1P!

CRASH-BANG-WALLOP! BL is certainly fun! Duster, I would definately recommend 5s A123 over anything else- in 2p configuration it is more or less perfect.

Thanks all- I will follow up on your suggestions.
I just couldn't stay away (such power is addictive), so I took it for another run in the evening last night- being REALLY careful I got a few nice runs around the yard. Too much trigger travel and WHOOMPA! the world turns upside down!
Thanks patrick, duster360, suicideneil, mkrusedc, aqwut I have learned a lot from you all. Duster_360 the power-up sequence works as I wrote, but any other change in the order give an over-voltage alarm. I guess if I had my time again might start with 4S but this is really a rush to drive, and I suspect a better radio and more circumspect driving in a bigger space would have saved some trouble....
Today I'm off work so I might try to fab up some battery trays for the A123s. Thanks!