Swapping out to a smaller supercharger pulley is the easiest way to add power to your 2003-2004 Cobra short of a tune. However, the smaller you go, the less contact area the belt has on the pulley. This leads to the belt slipping.
Luckily BilletFlow devised the solution by way of this Snub Idler Pulley & Bracket. If the belt is slipping, then you are not achieving full boost. This snub idler will not add power itself, but the elimination of belt slip allows full boost which is where the power increase comes from. It utilizes a 100mm Idler Pulley & is a simple bolt on installation. It is black anodized for long lasting good looks.