all the light cars we had in for 4 wheel alignment (hillclimb and sprint) needed loads of camber on the front
softer springs and firm damping also improve things as do softer tyres and lower tyre pressure
its just a side effect of not having any force pushing the thing down
all made worse buy having no body roll to soak things up
and a low more centered c of g
castor is only there to pull things stright and keep the thing going straight (what the offset mushroom should help)
if the start of a light turn feels unresponsive its could be too much toe out to twitchy and its mostlikly to be toeing in too much or the rear toe in reverse
if you ahve a problem later in the turn (half lock) it could be a problem with ackerman angle (not usualy ajustable) its basicly the angle of the tyre to its tyre path when driving in a circle as all tyres will have a diffrent radius of path so you could have toe in or out when the steering is turned
only way i can think of ajusting this on a roadster is to change the length of offset to the arm where the TRE mounts from the kpi line (note offset mushrooms have changed this length making its effective length longer) on or move the rack postion or change its rack length so the inner track rod pivots are a diffrent distence appart
rwd cars should toe in slightly fwd toe out at the front btw
also worth pointing out almost all production cars have positive camber to match the convex road serface (top out bottom in) not plum stright as you may think
im going to start with rear straight, front neg 1.5 deg camber and a tiny amount of toe in and the rest is trial and error with a thing like the roadster
also if you change the ride hight the hole lot will be out and you need to ajust it all
all just one big bag of worms realy
