I have just aquired a Traxxas Rustler and am in the process of converting it over to brushless. I already have the motor with is a Medusa 4800kv and I already have the battery that I am going to use which is a Turnigy 3000mah 11.1 lipo. What I need to know are some good recomendations for speed controllers. I am going to be doing top speed runs with this thing to see just how far I can push it. Let me know what you guys think.

Tekin RS Pro
Tekin RS
Tekin RX8
LRP SPX
LRP SSX
LRP ???
Speed Passion GT 2.0 (non LPF)
Speed Passion GT 1.1 (non LPF)

I think sums it up for the higher end ones.
Those would be my picks from most desired to least.
But also Most expensive to least expensive. Tekin Drules .....

I do not want lrp they do not even make a speed control that will hold 11.1v

A Mamba Max is the best ESC made for what you want to do. I have used many speed controls and nothing even comes close.

There are a couple of guys online who have modified their Mamba Max ESC to accept a 4s or more lipo using a CC BEC. Does anyone know how this is done?

You could get a r1 pro to keep cost down I have heard people running 5 cell as long as you disable bec

Mamba Max pro should be out in a week or 2 and handles 6s. By the way, does anyone have the dimensions for the pro? I'm hoping it will fit in my mini revo.

L: 1 3/4" W: 1 7/16" H: 1 3/8"
You will want to wait for the MMPro. Not even a question.

So its a wee bit longer, and a wee bit narrower, and a bit higher than the mamba max. This may fit perfectly on a mini revo. Sweeeet.

Also there is a fan on top that comes right off. Runnin in a mini you would not need it so there is a bit more room.

all the above are good, but if you are looking for an idea of what others have used with your setup, check out http://rcgearing.com

The limit in MM is the internal BEC - so to try to run higher than 3S, you run the esc with the onboard BEC disconnected. A separate external BEC is used to supply the power for the rx and servos.

Take a 6" servo extension and pull the middle wire out of the male connector and tape it to the rest of the wires so its stays out of the way. Plug the esc rx wires into the servo extension and into the rx.

You can do this with the wire off the esc, but sometimes replacing the wire doesn't leave you with a good connection here when you want to convert back to normal. Using the servo lead doesn't compromise the esc connection.