TeamThibault

So when do install shims or remove shims from bulkheads ?
I know it changes your roll center but not sure when to it?
Yes I'm still learning

Qatmix

The roll centre is the theoretical point around which the car rolls.

Rc onroad cars have roll centres lower than their centre of gravity, so think of the roll centre as a pivot point, when the car steers the car leans around that point, the closer they are together the less it will roll, the further apart the more they will roll.

So adjusting the front and rear inner camber links on the bulkheads is a big tuning option after tyres and springs. (Note you can do adjustments on the lower arm pivots and outter arm upper links as well but let's keep it simple and discus the inner bulkhead ones)

Adding more shims on the inner bulkheads lowers your roll centre. This essentially gives you more grip into a corner as the car rolls more and the outter wheel will dig in.

Removing the shims raises the roll centre. Making the car roll less and keeping more speed at the corner and transferring less weight to the outside wheels.

So tuning basics are as follows:

Lower front roll centre (more front chassis roll):

• More on throttle steering out of a corner
• Makes car less responsive

Higher front roll centre (less chassis roll)

• Decreases on throttle steering
• Car more responsive

Lower rear roll centre (more chassis roll at the rear):

• More grip on throttle
• Less weight to the rear but more grip

Higher rear roll centre (less chassis roll at the rear)

• Less on throttle steering
• More responsive when off throttle (chicane)
• Moves more weight forward off throttle.

I hope the above makes sense in on the train using my iphone so it's hard to type