I don't think the suspension has been messed with on my car but the 18" wheels and 40 profile tyres are maybe a lot to do with it. I hate the harshness of the ride and am looking at options to improve it. I am thinking of swapping my wheels for 17's. a bit annoying as the 18s have 4 brand new tyres on and I quite like the way they fill the arches but the ride quality suffers. Anything else I can do?