Audi S4 B9 Performance Parts & Tuning Mods

Top Brands For Audi S4 B9 Upgrades

The Audi S4 B9 is well supported by several top brands, offering everything from exhausts and intakes to suspension kits and styling upgrades. Below you will find leading manufacturers supplying proven performance parts and tuning options for this platform.

Exterior Styling Upgrades for the Audi S4 B9

For your Audi S4 B9, exterior styling mods like body kits, spoilers, splitters, diffusers and custom grilles can really sharpen its presence on the road, giving a more aggressive or refined look to match your build. These visual upgrades help your S4 B9 stand out from the crowd with a unique, tailored style.

Suspension & Handling Upgrades

The Audi S4 B9 is a quick, capable saloon out of the box, but there is plenty of room to sharpen its cornering and agility. A good starting point is tyres, since a quality set of performance rubber transforms grip, steering feel and braking confidence straight away. Combine that with uprated brake pads, braided lines and performance brake fluid, and the S4 feels much more composed on fast road drives or the odd track day, with far less fade and a more reassuring pedal. From the factory the S4 tends to play it safe with mild understeer and a fairly soft set up, which can dull feedback when you push on. Lowering springs or height adjustable coilovers help reduce body roll and improve stability, while quality dampers keep the ride controlled rather than crashy. Chassis upgrades like stiffer anti roll bars, fresh performance bushes and front strut braces tighten everything up, making the car more responsive on turn in and more playful on the throttle, without ruining its daily comfort if you choose parts sensibly and upgrade in stages.

Audi S4 B9 Performance Parts FAQ

What are the best first performance mods for an Audi S4 B9?

For most Audi S4 B9 owners, the ideal starting point is an ECU remap or tuning box, paired with a decent panel filter or intake upgrade. This gives a noticeable lift in horsepower and torque without needing to pull the engine apart.

After that, a high quality cat-back exhaust system, uprated spark plugs and fresh high spec oil help the 3.0 TFSI engine breathe and run more efficiently. These basic tuning mods set a solid foundation for any future performance upgrades.

How much power can I gain from an ECU remap on my Audi S4 B9?

A well developed ECU remap on the S4 B9 3.0 turbo V6 can deliver strong gains in both horsepower and torque, especially in the mid-range. You will feel sharper throttle response and stronger pull in-gear, which makes the car much more lively on the road.

Exact figures vary depending on fuel quality, supporting mods such as intake and exhaust, and whether you go for a conservative or more aggressive tune. The key is to use a reputable tuner who understands this specific Audi platform, and who can keep reliability as a priority rather than simply chasing numbers.

Will tuning my Audi S4 B9 affect reliability or longevity?

Mild to moderate upgrades, such as a sensible ECU remap, intake and exhaust, are usually fine for a healthy S4 B9 as long as servicing is kept up to date. Regular oil changes, quality fuel and proper warm-up and cool-down routines all help keep the turbo and drivetrain happy.

Once you push into higher boost levels, hybrid turbos or track-focused mods, supporting upgrades become more important. At that point you should consider improved cooling, stronger brakes and possibly transmission software updates to maintain reliability under harder use.

Do I need any supporting mods with a remap on the Audi S4 B9?

For a typical Stage 1 style tune on an Audi S4 B9, you can often run the ECU remap on an otherwise standard car, provided everything is in good condition. Many owners still choose to add a performance panel filter or intake kit and a freer flowing exhaust to let the turbo work more efficiently.

If you plan to go beyond basic tuning, for example higher boost levels or track days, it is sensible to look at uprated intercoolers, better brake pads and fluid, and possibly transmission software to make sure the gearbox and cooling systems can cope with the extra performance.

What suspension and brake upgrades are worth it on an Audi S4 B9?

The S4 B9 is fairly capable out of the box, but a set of quality lowering springs or coilovers can tighten up the handling and reduce body roll without ruining ride comfort if you choose the right kit. Uprated anti-roll bars are another popular handling mod and help the car feel more planted in corners.

On the braking side, performance pads and high temperature brake fluid are a smart first step, especially if you drive the car hard or use it on track. Later on, you can consider bigger discs or a full big brake kit for more serious fast road or motorsport use.

What wheel and tyre setup works well on the Audi S4 B9?

Most Audi S4 B9 owners upgrading from stock alloys move to lightweight 19-inch or 20-inch wheels, which can sharpen steering feel and improve the look of the car. Sticking to sensible widths and offsets is important to avoid rubbing and to keep the ride usable on UK roads.

A good performance tyre makes a bigger difference than many people expect. Investing in a quality UHP (ultra high performance) tyre in the correct load rating and speed rating will give you better grip, braking and traction than simply going for the widest possible rim and tyre combo.

Is a full exhaust system worth it on the Audi S4 B9?

A cat-back exhaust upgrade on the S4 B9 is a very popular mod, as it improves sound, reduces weight in some cases and can slightly improve flow. You get a sportier tone without necessarily making the car too loud for daily driving, especially if you choose a resonated system.

For more performance focused builds, pairing the cat-back with a high-flow downpipe and an appropriate ECU tune can release further gains. Any change to catalytic converters or lambda sensor locations should always be matched with suitable mapping to avoid warning lights and to keep the engine running safely.