The B8 Audi S4 is a monster of a Super Sport Sedan – from the getgo, whether you’ve the B8 S4 or the later B8.5 Audi S4, the fact is that you’ve got a great platform to start off with, but it can be AMAZING if you just take care of the few nagging details that take away from the car.
In this article we’ll be going over the basic modding options available to you for getting the most out of your B8 or B8.5 Audi S4, ranging from making it look and sound better to outright making it faster – all laid out in a straightforward, easy to follow manner.
#1 – Wheels
The OEM B8 Audi S4 Wheels range from “meh” to “bleh”- while I’m sure SOMEONE out there likes the OEM wheels, but most of us aren’t exactly impressed by the stock wheels. Check out the difference a set of HRE Flow Form FF01 wheels made on the S4 above. Pretty dramatic, wouldn’t you say?
It’s a universal truth for virtually every car on the market, all cars look better on a nicer set of wheels – doesn’t matter what make or model, from Audi models like yours to wildass italian Lamborghini exotics. The wheels are a fairly large portion of the car’s side profile, so a set of aftermarket wheels for B8 Audi S4 is a great way to give your S4 an accent that’s uniquely yours.
Audi B8.5 S4 on HRE FF01 Wheels in Liquid Silver 19×9.5 / 255/35-19 Michelin Pilot Super Sport
As far as style goes, there’s a wide variety of options to suit every budget and taste – from affordable cast wheels to beautiful bespoke Modular forged wheels, we’ve got an option that’s perfect for you and your exact S4.
With the B8 and B8.5 Audi S4, the body lines and cleaner styling calls for a wheel that pairs nicely with the car’s styling language and your personal tastes. We offer stylish wheels from HRE Performance Wheels, Forgestar, Klutch, BC Racing, Avant Garde, WatCooled IND, Niche Wheels, MRR, TSW Wheels, VMR Wheels and more.
We’ve shown you some HRE’s, check out a few examples that’ve been popular for the B8 S4.
Forgestar Wheels are another high quality option befitting your S4 – like the HRE FF01s, Forgestar Wheels are Rotary Forged aka Flow Form – meaning they’re both lightweight and strong. Forgestar F14 Wheels for Audi are a popular choice.
The stylish Forgestar CF5v Wheels for Audi is another popular choice that looks especially good on an S4.
VMR Wheels also offers some great options for the B8 Audi S4, like VMR V810 Wheels for Audi which are flow-form, rather than cast like the V7## series of VMR Wheels, meaning that they’re stronger and lighter than the cast versions.
If you’re on a tighter budget and a set of Flow Form wheels isn’t in the cards for you this fiscal quarter, VMR Wheels also has some other great choices like VMR V710 Wheels for Audi, which offer cleaner styling than the OEM wheels at a lower pricepoint if super-light or bespoke wheels aren’t your biggest priority.
TSW Nurburgring Wheels for Audi are also another great budget option.
Of course, these are just suggestions – there are dozens of wheel styles available and far too many to cram into one post, so check out our selection of wheels for B8 Audi S4 here.
Next up after wheels is giving the car a drop. Given the fact the cars are engineered with an AWD system, you can bet they’re designed with enough clearance to get around fine in snow belt states, meaning that even on a super-sporty S4 there’s still a good bit of wheelgap. There are a coupe of different options for B8/B8.5 Audi S4 Suspension Upgrades available, and each class of suspension product has its own pros and cons. We’ll lay out the basics and some of the pros and cons so you can decide for yourself exactly how you want to get low, and by how much lower.
The most “minimally invasive” way to lower your Audi is a set of springs for B8 Audi S4, which replaces the OEM springs with another, shorter set of springs for enhanced handling performance and a superior look – the S4 above is sitting on a set of H&R Sport Springs for B8 Audi S4 – it basically eliminates the wheelgap but isn’t super aggressive – and it’s set permanently at this height. You can’t adjust them. But the springs themselves are very affordable. We offer Lowering Springs for B8 Audi S4 from GMG Racing as well.
Lowering Springs are very affordable only in terms of the cost of the parts themselves, if you factor in installation costs for first installing the springs, then taking it all apart again a few thousand miles later when the OEM shocks are worn out, the cost difference relative to coilovers gets smaller and smaller.
It takes the same amount of time to install a set of coilovers as it does a set of lowering springs, and you get the added benefit of a higher quality shock absorber unit – which may even be adjustable – that’s been designed to work with the lower ride height springs, and coilovers offer the flexibility to have precise control over how low the car sits.
Contrary to popular misconception, coilovers are not limited to ‘racetrack only’ use – nothing could be further from the truth – most of the Mod Experts here – myself included- are running coilover suspension in our own personal daily driven vehicles. The real kicker is that sometimes coilovers can be MORE COMFORTABLE than the OEM suspension, as was my experience in my own Fiesta ST after installing a set of coilovers from ST Suspensions.
KW Suspension Coilovers for B8 Audi S4 are one of the finest options available for your B8/B8.5 Audi S4 Suspension, offering adjustable height, bound, rebound – with their stainless steel finish, these coilovers will stand up to whatever road grime and crap the snowbelt states can throw at them. What’s more, if you have electronically adjustable shocks and want to retain that functionality while also lowering the car, a set of KW Height Adjustable Springs for B8/B8.5 Audi S4 are the perfect way to pull that off.
If you don’t live in a state where snow is an issue, or are on a tighter option, you can skip the Stainless finish, as that’s really not going to benefit you much beyond looking all shiny and pretty. The Sepang Blue B8.5 Audi S4 above is sitting on a set of BC Racing Coilovers for B8 Audi S4, which offer a 30-way adjustable coilover at a much lower pricepoint, meaning you still get the full range of adjustments available.
Let’s say you don’t want to hassle with all that adjustment. There are several options available that offer adjustable height but pair that with a fixed-damping shock absorber that’s been spec’d for your S4 to keep the ride comfortable? If you’re looking to lower the car but are still concerned about ride quality, look no further than Vogtland Suspension Coilovers for B8 Audi S4. These TUV approved coilovers feature Vogtland’s in-house-built springs paired with a Galvanized shock body from KW (the same type used for ST Suspensions) that’s been spec’d with comfort in mind. If you’re a bit sportier, ST Suspensions XT Coilovers for B8/B8.5 Audi S4 are a great option on a budget.
If you’re going racing with the car and are working with the shoestring budget the average grassroots racer has at their disposal, a set of Solo-Werks Coilovers for B8 Audi S4 are extremely affordable, but are a very no-frills set of coilovers – all of the functionality, quality and performance but with none of the marketing fluff or show-quality finishing.
Of course, if you want to get lower, there’s always Air Suspension from Airrex.
Which brings us to Exhaust Systems for B8 / B8.5 Audi S4. The OEM Exhaust system is pretty friggin quiet. It’s designed with German road standards in mind, which are much stricter than what cars have to face here in the states. Fortunately here in the good ol’ US of A, we can have a loud exhaust if we feel like it, because MURICA.
What makes a good exhaust system though? Is it the loudest one available? The one that makes the most horsepower?
The best exhaust for B8 Audi S4 – definitively – is the one you like the sound of most. WHOA. What a crazy reveal that was, RIGHT? That’s why listening to sound clips is so important.
AWE Tuning has really made a made for themselves with their reputation for attention to detail – and controlling the tone of an exhaust system is something that AWE specializes and prides itself on, spending hundreds of hours developing and testing their exhaust systems before releasing them to the public, and most AWE systems are very customizable, allowing you to make the system louder or quieter based on your tastes. They offer two main versions – the perfect-for-street-use AWE Tuning Touring Cat Back Exhaust for B8/B8.5 Audi S4 – and the super loud, “let’s be a racecar, make my ears bleed!” AWE Track Edition Cat Back Exhausts for B8/B8.5 Audi S4.
While some folks might think they want the “Track” version, really, if you want a LOUD exhaust on your street car, you want the TOURING version, but without resonated downpipes. Listen to the stark difference between the two and see for yourself.
We have several other options for the S4 available as well, like the Neuspeed Cat-Back Exhaust for B8 Audi S4 models, which offers a slightly different take than AWE does on its exhaust design for a totally different sound out of your supercharged V6.
Another great option for your B8 S4 Exhaust is available from Milltek Sport. Like AWE, Milltek also offers their Cat-Back Exhaust for B8 Audi S4 in resonated and non-resonated forms, and Milltek updated the system as the Milltek Cat Back Exhaust for B8.5 Audi S4 is also available. Have a listen to the sound clips below.
Milltek Catback Exhaust for B8 S4 – Non-resonated
Milltek Catback Exhaust for B8 S4 – Resonated
Remus Innovation, another quality exhaust manufacturer also offers the Remus Exhaust for B8 Audi S4. We don’t have any examples of this system actually installed on an S4, but we were able to find this video.
An exhaust system for B8 S4 will free up a little bit of power, and opting for sport cat or catless downpipes when you are getting a system will also help keep the motor running a little cooler with that supercharged V6 and let you enjoy the unique engine note a roots supercharged motor has to offer.
Of course, if you’re not sure what your best options are, you can always chat with a Mod Expert and they can point you in the direction of an exhaust system you might like based on the traits you’re looking for – give em a call at 714-582-3330, chat live at ModBargains.com or simply stop by the ModAuto showroom in La Habra, CA Monday thru Saturday 8a-5p and speak with an expert in person.
#4 Stand Apart with an Exterior Look that Says YOU
If you’ve already picked up a set of wheels, lowered the car and done whatever you’d like with the exhaust system, then it’s time to look at making that S4 look a bit like it belongs to you, rather than just another anonymous 2 year lease.
If there’s one negative thing you can say about Audi’s styling, it’s that sometimes the Germans can be a bit “sterile”. Fortunately, changing up the aesthetic of your B8 or B8.5 Audi S4 is easier than you might think, and there are quite a few options on the market to help you create an aesthetic to your B8/B8.5 Audi S4 Exterior to create a combination that suits your style.
If you want something slightly more aggressive but still subtle, consider a DTM Style Carbon Fiber Front Lip for B8 Audi S4, which extends the front end slightly and the ends turn up for a subtle canard effect.
This ultra-subtle Carbon Fiber Front Lip overlay for B8 Audi S4 is a conservative way to add a little accent.
For those seeking a setup with a bit more portrusion to it, the Deval Style Carbon Fiber Front Lip for B8 Audi S4 offers an easy way to get that kind of look.
The STVBEK Front Splitter for B8 Audi S4 offers similar styling that offers a slight aerodynamic advantage and a more race-inspired looking splitter.
Then there’s the grille. The OEM S4 grille has that wonky license plate cutout that’s kinda ugly. The RS4 style grille for B8 Audi S4 without the license plate bar is a much more attractive front grille for the car and is available here.
When we install a RS4 Style Grille for B8 Audi S4 here at the shop, we also plastidip the crash bar behind the grille black, as otherwise the unsightly crash bar will be clearly visible.
Then there’s the side skirts. There’s really nothing that you can do about the side profile of the car as very few manufacturers even offer anything for the sides of these cars, strangely enough.
If you’re looking for a more aggressive rear end aesthetic the R Style Carbon Fiber Rear Diffuser for B8 Audi S4 will do exactly that, framing the quad exhaust tips nicely.
If you’re just interested in adding a carbon fiber accent to the rear, this OEM-style Carbon Fiber Rear Diffuser for B8 Audi S4 is shaped almost identically to the OEM panel, but produced in carbon fiber rather than body color.
Want a subtle hint of aggression without overdoing it? The Eurogear USA Style Carbon Fiber Rear Diffuser for B8 Audi S4 offers that kind of aesthetic.
These are just a few of the options available to you when it comes to making your B8 Audi S4 Exterior look like it’s YOUR car.
#5 Powering Up Your S4’s Performance
Now let’s talk about power and performance. There are a couple of key things to address when you’re modding for optimal B8 Audi S4 Performance. The 3.0 TFSI V6 is a different animal than many other cars and has unique problems specific only to roots supercharged cars.
The Roots blower on the 3.0TFSI V6 engine is great at making low end torque, but like any roots blower it has its shortcomings that need to be addressed as well. Namely, HEAT SOAK. Yup, the same problem that plagued my old 1990 Ford Thunderbird Supercoupe (3.8 Eaton Supercharged 5MT) plagues Audi’s latest n greatest sport sedan, and it’s gonna rob you of power the same way that it did to that old Ford, despite the massive difference in age.
AWE Tuning found that in testing, their 3.0TFSI powered S5 (the world’s fastest Full-Weight, Full Interior S5) was losing nearly 30whp after just a few WOT pulls on their dyno. Being ones never to leave something “half done”, AWE then set out designing this beefy cooling setup.
You have a few options for combating the insane levels of heatsoak these cars suffer from – both from premier names in tuning. AWE Tuning, a long time Audi specialist, offers the AWE Cold Front Cooling System for the B8/B8.5 Audi S4/S5 3.0 TFSI, which replaces and augments several key cooling components to ensure the motor stays cool and producing its intended output, pull after pull.
However, the cooling problem is enough of an issue that AWE wasn’t the only ones to notice – Supercar tuners ALPHA Performance have rolled out their own to keep the S4 running nice and cool – the Alpha Performance Boost Cooler Kit for B8/B8.5 Audi S4.
Yeah, these systems are a bit pricey, but the cooling system is the #1 issue that you should address if you’re looking to get more power out of your S4.
So after you address the cooling system, then what?
Upgrading the intake isn’t without its gains, as you can pick up at least 15hp / 10tq by installing a performance air intake, and a free flowing intake will allow you to better hear that trademark Eaton Roots-Blower whine. “WRRRRRRRRRRRRRRRRR” has never been a more beautiful sound to behold.
You have a couple of options for your intake upgrades for the 3.0 TFSI – the AWE Tuning S-Flo Intake for B8/B8.5 Audi S4 3.0TFSI, which is the more “OEM+” option and a touch more conservative.
If you’re okay with a more aggressive look under the hood, Injen technology offers a great solution for the 3.0 TFSI. Injen’s intake replaces the OEM upper airbox lid and fits a high flow filter and tubing to deliver a gain of 18whp and 14wtq at all four wheels.
Beyond the intake and the cooling system, what other upgrades are available? Well, the fun thing is that increasing power is surprisingly easy with a Roots-Supercharged engine. Want more boost? Just change the pulley! It’s that simple. And AWE Tuning has a solution that allows you to do just that.
AWE Tuning offers a combination of a pulley/belt combined with a software reflash to yield a whalloping gain of up to 100 crank hp and 80 crank tq over stock.
As you can see, there are a number of different ways to go about building more power with your 3.0 TFSI engine – if you’re not sure about what the best option for you might be or have questions, feel free to ask a Mod Expert, call 714-582-3330 or chat live at ModBargains.com
The B8 S4 can get moving with some serious authority – however, the OEM B8 Audi S4 Brakes can be a bit undersized for the job, especially if you’re an aggressive driver (you know who you are) or plan to track or canyon the car on a regular basis. That means that with all that thrust getting you moving, the OEM brakes might fall short when it comes time to suddenly hit the brakes and come to a stop.
There are a couple ways to beef up your stopping power- we’ll start with the easiest. You can always go with the Audi Sport Big Brake kit, but let’s say that you don’t have the budget for 24-Hours-of-LeMans grade stopping power. (We didn’t say that was the cheapest, just the easiest.)
One of the more cost-effective ways to beef up the B8/B8.5 Audi S4 Brakes‘ stopping power is more affordable than you might think – a set of StopTech Drilled & Slotted Brake Rotors for B8 Audi S4 are a great place to start, pair these with a set of StopTech Street Performance Brake pads for B8 Audi S4 for a noticeable increase in stopping power.
If you’re on a tighter budget, R1 Concepts offers their slightly-less-fancy E-Line series rotors in plain front / plain rear , slotted front / slotted rear, or both drilled/slotted front with drilled/slotted rear for Audi S4 applications.
The last inexpensive-but-effective Brake upgrade for the S4 is an upgrade that’s effective on nearly every make and model – a set of NeuSpeed Stainless Steel Braided Brake Lines for B8 Audi S4 will give your brakes a more positive feel, a firmer pedal and the stainless steel braided construction does not expand under pressure like the OEM rubber lines sometimes can, thereby denying the brake fluid a potential place it can boil and create air bubbles in the system.
By installing an upgraded set of Brake Rotors, superior compound brake pads and stainless steel brake lines all together, you’ll net a major increase in stopping power for a fraction of the expense of a big brake kit.
That said, if upgraded versions of the OEM components still aren’t enough, we also offer the AP Racing Big Brake Kit for B8 Audi S4 here to give you enough stopping power to give yourself whiplash several times over.
We hope the above 6 best mods for the B8 and B8.5 Audi S4 (3.0TFSI) has shown you what you wanted to know about the basics of modding the B8/B8.5 S4 as a platform, but we should mention once again that this is simply a general overview and there may be more options we weren’t able to cover here.
If you have questions about modifying any aspect of your B8 or B8.5 Audi S4, we invite you to consult our team of Modification Experts. Each member of our team owns and modifies their own personal vehicles and have years of firsthand experience building modified cars – give them a call at 714-582-3330, chat live at ModBargains.com or just stop by the ModAuto showroom (which is also our install facility) in La Habra, CA on Lambert Rd at Harbor Blvd Monday thru Saturday, 8am – 5pm PST.
Thanks for reading, and we’ll see you next time!
Story & All Original Photos by Nick Gregson
Select Photos Courtesy Manufacturers