Had my springs tested by a dealer , he changed the shock absorbers with monroe's.
I'm not confident about cornering performace of the 155.Something to do with the chasis , you can change the entire set-up but ik will cost you a small fortune ...is it worth it?? Only when you are a regular circuit user I think.
I take corners faster with my bike , not normal considering that cars most of the times have faster corner speeds.
Lowering the car , a harder set of springs , big spoiler for downforce , soft race tyres .
But normal purpose suffers under these adjust's.