build a gmaxx and i need help

[JoFreak]

If you wan't to run your truck very fast it depends on if you plan on doing that onroad or offroad. Offroad speedruns with a very hard suspension aren't much fun since your truck will bounce all over the place and won't have any grip.
Since you want a low setup you should definetly get the front shocks.
I just don't get the point of first choosing the FLM chassis with higher center of gravity for bashing and then going all low with the suspension
And it has nothing to do with which shock towers and suspension you choose if you can run a 4 shock setup.
Those would be the shocks UE sells as supershocks: http://www.amainhobbies.com/product_...ed-Shock-Set-2
As Jamara seems to be reseller for most of Europe you might wann try to get those shocks from a local hobby shop: http://neuershop.jamara.com/index.php?a=3190&lang=eng. Those should be the same shocks but are possbily cheaper to get.
But you're most likely to need harder springs than supplied with the kit and thicker oil than what I recommended since that was for 8 shock setups.