Several questions
 

I sold my brushless LST2 several months ago as it was just too much.

I have my sons Emaxx right now. We have been running a MM ESC/5700 & 3S Lipo 4000 Maxamps for a while. The setup came out of my B4 for fun one day and it ran so well it's been in there ever since. I've got it geared as low as I can go 10/72. It run's good on(2) 6 cell Nimh packs and very fast on the single 3S Lipo.

I was running 5s on my LST and the Maxx is not nearly as strong. But I'm not looking for that anymore.

I thought about going to the HV-Maxx 4.5 but it's kind of $$ when I already have a great ESC with Lipo cutoff. If I go Lipo I want to use my existing pack and maybe purchase one more identical and use the MM ESC built in cutoff. 2 packs parallel 3S 4000 = 8000MAh = long run times and built in Lipo cutoff.

If I bought one more 3S Maxamps pack and ran them parallel what motor would I want. I looked at the Feigao 7XL, 8XL, 9XL but the KV seem kind of low for what I want. I can't find any info on the L size cans.

The 5700 is nice but I can tell it's really not meant to push a monster truck around. The XL motors are very cheap and would be an easy upgrade.

I would be going from 5700KV/V to 2400Kv/V on the 7XL.

What do you guys suggest?

Not sure how well it would run, but the 7xl on 3s would be your best choice for heat disipation. You are running about 30mph on 3s with the 5700. If you want to keep the same speed, I am sure it would be ok. With 8000mah worth of batteries you would have enoght capacity too. The L can motor would probably work too, the 9l works well on 3s. The xl can will run cooler for longer than the l can, but both will heat up eventually. The 9l on 3s will need 66/20 gearing to be as fast as you have right now. The 7xl would need 66/23 to match that. I have had good success with the L cans and the xl. I think someone else here runs a 7xl on 3s so maybe they will chime in.

Just curious as to why the LST2 was "too much"? I'm considering purchasing one for conversion, and would much appreciate your insight.

i'm considering a brushless LST2 as well, and am also curious about your 'too much' statement.

it makes it more appealing, lol

You better have very deep pockets is what I mean by "too much."

Lipo is getting cheaper by the day though.

I had to upgrade almost everything on the LST2 to handle the brushless power and 5S.

I would think most any rig on 5S would require major upgrades. Besides upgrading the drive train, did you break anything such as internal tranny gears.

The 2 speed would never work right with the 5S power. I finally made a custom one speed and 8man's +2 pinions and never had trouble again.


What would be the rough equivalent to the HV Max 4.5 motor in a Feigao? Something like a 10L or 12L? Or is it more like the XL size?

I believe the HV4.5 is rated at 4800kv (6.5 is 3100), and size wise its just a few mm shorter than an XL can motor. The catch is that the rotor/magnet is only 380 motor diameter, which is why it struggles to propel larger/heavier truck around. I have the 6.5 in my Gmaxx and it is only reaching 30mph or so, which means the 4.5 would be faster, but a lot hotter and may fry. You can find the kv ratings of all the feigao motors in BrianG's speed calculator, which is in his sig.