Improved cooling leads to smoother and a more consistent power delivery. The APR intercooler upgrade for the S4 is a combination of RS-4 intercoolers and APR designed and developed peripheral parts. The RS-4 intercoolers provide cooling superior to that of the stock S4 intercoolers. Besides being larger, they offer better build quality utilizing aluminum end tanks that are welded to the radiator cores. However, the highlight of the kit is the APR custom designed silicon hoses.

The hoses included in the kit are true custom hoses. They are not a combination of off-the-shelf or modified parts. Instead, they are specifically designed for optimized flow by minimizing straight sections and maintaining a maximum radius throughout. These are true one-piece silicon hoses made from APRs own tooling created in-house. These hoses, along with the RS-4 cores, insure the most thoroughly developed S4 intercooler upgrade option on the market.

The kit consists of two primary parts: one, the intercoolers themselves, and two, the hose kit and associated hardware. The hose kit is made up of two turbo to intercooler hoses, two intercooler to bi-pipe hoses, eight clamps, the horn re-location bracket, and cap screws and lock nuts.