Yesterday I went on a little tangent about the S4, particularly, the B9 S4, where I worked through my actual feelings about Audi’s sport sedan lineup since the introduction of the model in 2000. Like any writing, it was an opinion. Just a stream of consciousness as I meandered my way to an understanding of what I could appreciate about the car. The article I had initially intended to write, however, was recommendations about what to do for your B9 S4 to make it the best possible version of itself. Today, that’s what we’re going to explore. These are the S4 parts we suggest to get the most out of Audi’s 3.0T Quattro sport sedan. 

If you are one of the fortunate Audi B9 S4 owners out there, chances are, you already know how amazing the car is, even without the DSG or manual transmission options offered in previous generations. With it being a new car, maintenance isn’t really an issue, even if you picked yours up second hand. Of course, oil changes, tires, and brakes are all continuous services, so we shouldn’t need to explain that those need attention at recommended intervals. That said, we highly recommend you switch to LIQUI MOLY oils and additives to keep everything lubed properly to ensure a long life from the engine, transmission, and differential. 

As long as you stay on top of the recommended services, you should enjoy a long life with Audi’s latest S4. But what if the stock B9 S4 just isn’t exciting enough? Have we got some fun things to show you.

The stance/fitment scene is alive and well, but the S4, particularly the B9 S4, hasn’t really made its way into that community with any regularity. There are some great examples of stanced B9 S4s out there, but, with all the R&D and tech spent in designing the suspension, we would hate to just throw it all away. Of course, an Air Lift setup is a fantastic way to achieve instant ride height perfection for any situation, but that choice ditches almost all the suspension for aftermarket components. A popular trend lately has been actually just using lowering springs with stiffer rates to achieve that perfect fitment without sacrificing Audi’s supreme ride quality. Whatever you choose, be it Air Lift, coilovers, or Racingline springs, lowering the B9 S4 is, in our opinion, one of the best things you can do in terms of looks. Just be wary: you may make a few sacrifices in the comfort department if you decide on bags or coils. 

Naturally, with a lowered ride height, you will want to round the look off with some wheels. The wheels we chose for our B9 S4 were Rohana RFX10 in silver that, frankly, look incredible. Upsized from the stock 18” alloys found on the B9 from the factory, they offer a fuller look to the wheel arches and vastly improve the stance. Our new Tekniform wheels are also a great choice, as they are lightweight, rotary-forged, and incredibly attractive in the 19” versions, though, there are almost infinite options. It just depends on what look you want, what specs you want, and how you want the car to sit. Just make sure you do your measuring twice before you order or stay with the tried-and-true B9 S4 fitment options we have cataloged on our site.

After wheels, tires, and suspension, you’ll likely be interested in what you can do to match the performance and sound to the new look of your B9 S4. The V6 3.0T engine is a stout one, good for 360 horsepower or so, and makes your right foot feel connected to a rocket ship rather than a big Audi sedan. Even so, it is a little too quiet for our liking. Our Cast Stainless Steel High Flow Catted Downpipe, which adds 34WHP, is a great start to building the perfect exhaust system. Next, our Center X-Pipe gives it a heartier exhaust note and frees up some weight. Finally, a Milltek Sport Cat-Back Exhaust System will open up the pipes entirely for the most aggressive sound when paired with our Downpipe and X-Pipe. This will surely satisfy your need for all the noise, pops, bangs, and turbo sound.

To protect your fancy new exhaust and all the rest of the underbits of your B9 S4, we developed the Ultimate Street Shield Kit, which includes a skid plate and tunnel shield made of high-strength, lightweight, aluminum that are designed to fit just like the plastic splash guards installed from the factory. These will keep you safe at your lowered ride height and prevent any undue concern over less than perfect road surfaces.

Moving to the engine, we honestly think all it needs is our ECS Kohlefaser Luft-Technik Carbon Fiber Intake and a bit of flare. Nowadays, everyone covers up their engines anyway. These covers, in theory, prevent some heat from affecting intake air temperatures, but in reality, they’re mostly just to make the engine look more attractive since modern intake manifolds, head designs, and other underhood components aren’t all that pretty. Gone are the days of looking at a bare big block sitting dwarfed in a massive and spartan engine bay. Now, everything is packed in like too many sardines in a tin. So, if we must have covers, we should at least have Carbon Fiber ones. Our Carbon Fiber inlet scoop, intake box overlay, ECU cover, and Radiator Support Cover tie the engine compartment together beautifully with that good, good carbon fiber weave hiding everything underneath. 

Continuing the theme of carbon fiber, now that we have addressed the stance, wheels, underbody protection, engine bay appearance, and exhaust sound of the B9 S4, we can move on to exterior modifications. In the new car scene, as we have said, most of these high-end performance luxury cars are close to perfect in the power and handling department. Changing the look and sound is all the rage, especially with a bit of motorsport inspiration and equally high-quality mods and upgrades that accentuate the striking, modern, and angular look of the B9 S4. Our exterior bits do just that. 

From back to front, our Carbon Fiber Trunk Spoiler adds a subtle, yet sporty, finish to the trunk with its upswept design. The ECS Carbon Fiber Rear Diffuser that sits under the bumper pairs nicely with the spoiler and gives the rear a distinctly track-inspired look, finishing off the rear with bits of glorious carbon fiber. Moving forward, our Carbon Fiber Side Blade Kit, another ECS In-House product, widens the overall appearance of your B9 S4 and matches the carbon motif for a more visually aggressive attitude. Finally, on the front bumper, our Carbon Fiber Front Lip Spoiler, Carbon Fiber Fog Grille Overlay Set, and Carbon Fiber Grille Accent Set make the total package complete. With carbon accents front to back on the B9 S4, it takes on an entirely different character and menacing presence that matches the sound, stance, and performance with a distinct style.

Of course, you can find all these upgrades on our very own B9 S4 for good reason. While some of our fleet cars are sporting 500+whp, incredibly aggressive wheels, Air Lift Performance kits, and even widebodies, the B9 S4 doesn’t need all that. Simple upgrades, like those mentioned, are all you need to set your B9 S4 apart and achieve that desirable motorsport-inspired look, feel, and sound, with the ability to pop the hood and show off carbon fiber at every angle, or leave it closed and enjoy the juxtaposition of rounded, angular, and boxy elements of the B9 S4 heavily accented with carbon fiber goodies that give it a ground-hugging look and hint of elegance. Once again, this is series of modifications we can speak to with experience, as you will notice their presence on our B9 S4, which distinguishes itself from the pack with its impressive stance, sound, and sense of completion. Be sure to check out our full list of Audi parts for your B9 S4 right here at ECS Tuning and stay tuned for more of our top mods, maintenance, and upgrades for your favorite cars on the ECS Blog.