Well as promised ive managed to find the site about what happens when you start to modify your car
the site address is www.Balancemotorsport.co.uk this site obviously sells you spares but more importantly tells you what can happen to your car when you fit that competition part
click on each section for eg brakes and see what can happed when for instance you just change the dia of your wheels/tyres hope you find it as interesting as I did 