hi guys , loads of info on these great pages , to much sometimes ,lol , i,m on 2012 z quite awkward at slow speeds as well documented , i,m not planning on going round the world etc but do want smoother operation , which mods will put me right please guys , do i need aftermarket cans ? will they make much diff after filter and fuel ? also can you purchase straight of here , ? headache coming on !! thanks in advance from windy raining england