Gear ratio for G2R brushless REVO

[osh0122]

Hi,
I just got G2R chassis couple days ago.
It was quick shipping from Mike. Thanks, Mike.

I got NOVAK HV brushless system from my friend, so I'm going to use this set-up first for G2R project with IB 3800 7cell pack. (I'll go with different brushless set-up later)

This is my first project of electric version. ^ ^
(I only know about nitro...)

I'm just wondering what gear ratio I have to use for this motor.
Any recomendation would be highly appreciated.

Thanks.