Project RS4 undergoes rear caliper paint, and arch and chassis rust proof and deep clean.

Project RS4: Rear Caliper Colour Coding & Arch Restoration

There’s something deeply satisfying about giving a performance car the attention it truly deserves — not just where you can see it, but where it really counts. Our latest stage on Project RS4 was all about the details: refreshing the rear brake calipers with a new colour scheme, tidying up the rear arches, and protecting the underbody for years to come.

Step 1: Colour Coding the Rear Calipers

The RS4 already has serious stopping power, but visually, the rear calipers were letting the side down. After removing the wheels, we stripped back the existing finish, degreased the surfaces, and masked up everything that needed protection.

Once prepped, we laid down a fresh high-temperature primer, followed by the new colour coat — perfectly matched to complement the car’s overall aesthetic. A few coats of clear lacquer sealed the deal, giving a glossy, durable finish that looks OEM+ and will stay that way under brake heat and road grime.

The end result? Subtle but purposeful — the kind of detail that makes a difference when you catch a glimpse through the spokes.

Step 2: Removing the Arch Liners & Addressing Rust

With the wheels off, we took the opportunity to remove the rear arch liners and inspect what was hiding behind them. As is often the case with older performance cars, a bit of surface corrosion had started to creep in — nothing major, but enough to warrant some attention before it could worsen.

We carefully wire-brushed the affected areas, treated them with rust converter, and cleaned everything thoroughly. Once dry, the freshly prepared arches were ready for protection.

Step 3: Wax Oil Treatment & Clean-Up

To keep the RS4 looking fresh underneath, we finished with a full wax oil treatment. This creates a flexible, rust-resistant barrier that helps protect the arches and inner panels from moisture and road salt. We also took the time to clean and dress the suspension components and inner arch plastics — because when you’re this far in, why not make it spotless?

Step 4: Ready for the Road

After everything was reassembled, the car looked incredible from every angle — even the bits you rarely see. It’s a small project that adds up to big peace of mind, knowing the RS4’s underbody and brakes are as immaculate as the rest of the car.

Want This Done to Your Car?

At Chips & Scuffs, we can carry out the same treatment on your car — whether you’re after custom colour-coded calipers, a full arch clean-up, or a protective wax oil application. It’s a perfect way to refresh tired components, prevent corrosion, and add a touch of individuality.

From detailing and minor bodywork to restoration-level underbody protection, we’ve got you covered. Get in touch today and let’s give your car the care it deserves.

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