Hi,

Take a look at this set-up. Would have been one of the last time the AE team in the UK ran a b4.x on carpet.

http://www.petitrc.com/setup/associa...ce20110116.pdf

A mid motor car will (should) be quicker. But you should be able to get an acceptable set-up on a B4.2

What I would suggest is to add weight to settle the car down.
Heavy front bulkhead, 30g stops the nose of the car lifting.
Slightly stiffer spring on the front, closer to 4lbs.

Worth trying a weight plate under the servo as well.

Rear
On the rear run as smaller a spur as you can, get the weight of the motor in as much as you can.
Move the shock to the middle hole, outside hole on tower. Car will generate enough side bite, no need for the shock to be on inner hole.

You can add weight to the rear as well.

For the tyres, are you trimming them? Trim rows off, front and rear to settle the car down an to stop it grip rolling.

You can also glue the side walls to settle the car down.

MiCk B. :-)