It's hard to believe that the B7 chassis is pushing twelve years old now. It doesn't appear a day over 5 years old in our opinion, and we think it still looks dashing. Over the past decade and change, we've had a chance to really hone in on the B7's shortcomings and identify the best performance upgrades to make this platform really come to life. When you consider it shares some of the same underpinnings from the B6 chassis as well, we've had ample time to determine what works and what doesn't.
Almost any B7 A4 owner with the 2.0T FSI can agree that the first modification to increase performance should be an ECU flash. It offers the most "bang for your buck" and truly wakes the car up from it's docile factory spec.
Wake Up That 2.0T FSI!
Directly from Audi, the 2.0T FSI can feel numb and rather unresponsive for a 2.0 liter turbocharged motor. It lacks the pep that one would expect from a small forced induction setup. Thankfully, recalibrating the ECU is as easy as plugging into the OBD-II port and uploading a new file to truly bring the 2.0T FSI to life!
034Motorsport spent countless hours perfecting the results for our B7 Audi A4 2.0T FSI Performance ECU Software to ensure impressive and consistent power under all circumstances. The Stage 1 flash utilizes 034Motorsport's proprietary calibrations to increase boost while optimizing timing and fueling maps with no additional hardware or modifications required. The results are a staggering 60 HP and 98 FT-LBS of peak power gains on 91 Octane! In addition to the new-found power, careful adjustments were made to improve throttle response for a more refined driving experience.
If you were to only perform one modification to the B7 Audi A4 2.0T FSI, the Stage 1 ECU flash is undoubtedly the best "bang for your buck" upgrade.
The factory catalytic converter is really good at providing clean emissions and bolting on to the hot side of your turbocharger, but that's about all it's good for. Some of us however, are more interested in increasing power and having a little fun behind the wheel. After all, it's not like we drive a Prius!
In an effort to make the B7 A4 a clean vehicle, the factory cat is massive and robs valuable horsepower and torque from the four cylinder turbo motor. After you've woken the car up with an ECU flash, it's time to tackle the next best "bang for your buck" power mod in the form of a more efficient High Flow Racing Catalytic Converter. The high-flow catalytic converter features a 250 cell stainless steel matrix that allows for exhaust gases to pass through easier, therefore reducing back pressure immediately behind the turbo and offering significant power gains.
The 034Motorsport High Flow Racing Catalytic Converter showed gains of 27 WTQ and 33 WHP on stock turbo tunes when tested on the dyno! In addition to the power gains, turbo spool occurs roughly 300 RPM quicker as well, meaning power comes on quicker after each shift. This complete drop-in upgrade fits the factory exhaust system and OE-Fit aftermarket cat-back systems as well, so no modification is required for install.
Power Gains Aplenty, Now to Improve Handling
Once you've added some power to the 2.0T FSI powerplant, it starts to feel more eager and willing to get you moving. The next step is keeping the newly added power under control in the form of suspension upgrades.
As you may have noticed so far, we keep referring to these "best bang for your buck" mods, meaning you experience the greatest improvement in vehicle characteristics while spending the least amount of money. By upgrading the rear sway bar to a stiffer unit, the B7 chassis develops a more neutral handling personality. Gone is the plague of understeer that these cars are known for, and instead the car becomes more responsive during turn-in and has less body roll when pushed to the limit.
The 034Motorsport Adjustable Solid Rear Sway Bar features two stiffness settings to dial in the amount of oversteer desired based on your driving characteristics and comfort level. Constructed from 25.4mm diameter solid spring steel, this upgraded rear sway bar is 100% stiffer than the factory RS4 unit when set to the "Soft" setting, and 125% stiffer than the factory RS4 unit when set to the "Stiff" setting. While other companies want you to buy sway bar pairs to achieve your handling goals, 034Motorsport engineered this Solid Adjustable Rear Sway Bar to be used in conjunction with the stock front bar for the perfect balance between neutral handling characteristics and street comfort.
By now, the motor mounts on a B7 A4 are likely pretty tired if they're original. The rubber will be fatigued, and fluid inside of each mount may even be leaking out, eliminating any of the dampening properties it was designed for. Furthermore, this failure will allow your engine to move more under acceleration and deceleration and leaving much to be desired from your A4's performance.
Never fear! 034Motorsport's Density Line Motor Mounts for the B7 Audi A4 were designed to be an upgrade from the fluid-filled factory mounts in every aspect. 034Motorsport Density Line Motor Mounts share the same shape and profile of the factory mounts to be a direct replacement part, but that's where the similarities end. Density Line Mounts are void-free and fluid-free, constructed from solid-filled high durometer rubber and feature steel bases.
Street Density Mounts are ideal for daily driven cars where added Noise, Vibration, and Harshness (NVH) inside the cabin is not desired. Using 50 Durometer rubber and solid filled construction (no voids), these mounts are roughly 25% stiffer than factory mounts. This allows for a secure drivetrain with enough compliance around town to not upset your significant other during date nights.
Track Density Mounts were designed for the speed freaks in mind. Constructed from 80 Durometer rubber and solid filled, these mounts are approximately 120% stiffer than the stock units. This means a driver will experience a truly locked down drivetrain with improved shifting feel and more direct power transfer, however an increase in NVH will be realized inside the cabin. If you autocross or track your car more than you drive it on the street, these are the mounts for you!
Following the same train of thought from the motor mounts, replacing those worn out transmission mounts with void-free, high durometer Density Line units will reward drivers every time they put their car in gear. Adding power is mighty fun, but leads to additional stress on drivetrain components left to cope with the new limits. After all, improving shifting feel and response is a huge part of what makes driving so pleasurable.
Street Density versus Track Density utilizes the same rubber compounds found in 034Motorsport Motor Mounts, 50 Durometer and 80 Durometer respectively. There are transmission mount variants for 6-Speed and CVT-equipped vehicles as well as Tiptronic cars. Take it from Ramon, a happy B7 A4 2.0T CVT customer who says, "it really is day and night compared to the stock mounts. So smooth and quiet, no vibrations under load, and the motor feels planted."
If you've been following this mod list moving from the front of the car to the back (excluding the rear sway bar section), the next portion of the B7 A4's drivetrain that needs some help is the rear differential. Similar to the factory motor and transmission mounts, the factory rear differential carrier mounts have voids in the rubber as well. These voids are designed to dampen the vibrations from the rear differential and in doing so, allow for flex and twist under load. While your Grandma might enjoy Audi's thoughtfulness here for a quieter ride, your performance wishes need to be satisfied.
The 034Motorsport Rear Differential Carrier Mount Inserts are an ingenious solution to limit rear differential movement for you adrenaline junkies. Engineered to perfectly fill the voids of the factory differential mount, the billet aluminum inserts act to limit movement under load while still utilizing the dampening characteristics of the rubber. Therefore, no additional NVH is experienced in the cabin, however differential movement has been severely limited during shifting, acceleration, and deceleration. The result is a tighter and more connected feeling from the rear end, giving the driver confidence when the roads get twisty.
Considering most B7 A4s are getting "up there" in mileage, the control arms and tie rods can wear out and lead to a vague and sloppy steering feel from the front end. These Audis use a lot of arms to link the front wheels to the chassis (8 to be exact) and ensure the wheels stay pointed where you want them to. When the rubber bushings degrade on the factory control arms however, steering becomes less precise and handling is hindered.
034Motorsport Density Line Control Arms are created to the same exacting standards as the factory units from Audi to ensure perfect fitment and strength. These direct replacement control arms feature solid rubber bushings constructed from a slightly higher durometer than OE units. This lends to crisper handling due to less deflection from the bushings, as well as longer life from a more durable part all-around.
If you're looking for a bit more adjustability from your alignment, then 034Motorsport Adjustable Upper Control arms are just the ticket. The high durometer inner bushings feature the same characteristics as those found in the complete Density Line Control Arm Kit, ensuring crisp handling and long life. The outer heim joints are comprised of Aurora Spherical Bearings with a Teflon race lining and a safety washer to ensure the spherical bearing will never separate. The best part of all is that these arms are completely rebuildable, from the bushings down to the pins, so owners can always enjoy responsive handling.
Whether you track your car and are looking to dial in your alignment, or your car is lowered and you simply want to reduce camber and minimize tire wear, these Adjustable Upper Control Arms can get you there. The heim joints are adjustable in 1/36" increments, equating to roughly 0.1 degree of camber to allow for a truly accurate alignment. Track cars and show cars alike can make the most of Adjustable Upper Control Arms with the precision they allow.
Look For Longevity From the 2.0T FSI
Another weak point of the B7 Audi A4 2.0T FSI was the factory PCV system. When subjected to constant heat from the motor, the plastic hoses and connectors degrade and crumble over time leading to boost leaks. Furthermore, as the first generation of direct injection from Audi, the 2.0T FSI motor is known for a bad case of carbon buildup on the valves and within the intake tract.
One of the best ways to minimize carbon buildup on a 2.0T FSI motor is to install a catch can kit. In doing so, you are redirecting oil and water vapor from the crankcase into a container where it can condense and drain back into the oil pan or be discarded periodically. A catch can safely eliminates one of the largest causes of carbon buildup and prolongs the efficiency and health of the 2.0T FSI.
The 034Motorsport Billet Aluminum Catch Can for B7 Audi A4 2.0T FSI was engineered to be the most complete and effective kit on the market. Constructed from billet aluminum, this catch can kit features a valve cover adapter plate, -10AN braided lines, intake manifold boost tap, and chassis specific mounting brackets. It's a no-brainer upgrade for any 2.0T FSI owners who want to get the most out of their engine and ensure it is performing optimally long into the future.
The factory air box is plenty efficient for vehicles still running the stock K03 turbo. When it comes to induction on the B7 A4 2.0T FSI, the weakest leak is the turbo inlet hose. The factory corrugated unit is made from rubber and can rip over time due to the extreme conditions it endures in the engine bay. The rubber can become fatigued over time as well and collapse from the suction created by the turbo, effectively strangling the motor.
Instead, the 034Motorsport High Flow Silicone Turbo Inlet Hose is constructed from high quality, automotive grade silicone with 4 layers of reinforced nylon to ensure it holds its form no matter what. The inside of the hose features a larger diameter with a smooth surface throughout, eliminating the turbulence found in the corrugated factory hose. All of this ensures that the intake tract to the turbo is free of obstruction and able to flow.
The B7 Audi A4 was an excellent evolution from it's B6 predecessor. Sharing many chassis components with the B6 while improving the powerplant and updating the exterior styling to the larger and more modern front grill helped the car stay relevant. Even a decade later, the B7 hardly looks dated and remains reliable as the miles continue to climb. With the right upgrades, the B7 Audi A4 2.0T FSI can transform from a docile commuter car to a lively and playful canyon carver.