To the average Joe, the Audi RS4 goes unnoticed. It looks like an ordinary A4, with the exception of a few sportier accents and different badges. But Matthew Collins has built an example that deserves more recognition.
Undeniably, the RS4 is an amazing machine, but Matt took it a step further. The 4.2-liter V8 is supercharged to deliver awesome all-wheel drive power, while custom-tuned Ohlins suspension keeps the chassis composed at all times. Stopping the car from triple-digit speeds isn’t a problem, thanks to massive StopTech brakes. Michelin tires offer endless grip on the street or at weekend track days. Yet the interior features European-spec seats and steering wheel plus an award-winning stereo system to provide the best of both worlds.
We were in the race to build the first supercharged RS4 in the US, began Max Gerson, co-owner of 3Zero3 Motorsports, the shop responsible for the majority of the build. Everybody has put big turbos on the 2.7T and 1.8T but once you supercharge an $80k car, you’re not modifying it. You’re building a supercar.
The road to building the ultimate RS4 had begun. Matt’s decision to buy one was simple. At the time, the RS4 was considered the elite among Audi’s lineup. However, many people were hesitant when Audi ditched the twin-turbo 2.7-liter V6 from the previous generation. Yet Matt didn’t hesitate.
He became close friends with staff at 3Zero3 who specialize in Audi, VW and Porsche. Together, they began the project by de-restricting the exhaust with high-flow Milltek downpipes and cats. A non-resonated system turned the RS4s growl into a lion’s roar.
From there, the factory Dynamic Ride Control system was ripped out for Stasis Engineering coilovers. It included Ohlins remote-reservoir dampers and custom-spec street springs. This would enable the system to react quickly to driver input, while still retaining a comfortable ride.
Hotchkis front and rear sway bars enhanced the suspension by reducing body roll. Just like the coilovers, Matt wanted to be first to have a PES supercharger kit. PES was first to market and we wanted the kudos of having the first supercharged RS4, explained Max. We also needed some hometown support since PES was a phone call away in Pennsylvania.
At the center of the kit was an Eaton M90 blower, commonly used as OEM hardware by Mercedes, Aston Martin and Jaguar for its instant power delivery throughout the powerband. For the RS4 application it provided a conservative 6psi of boost fed through an enormous liquid-to-air intercooler.
We’ve been really happy with the R&D on the PES kit, Max continued. We haven’t really had to troubleshoot any issues at all. The only thing left to do is squeeze that last 10% of power from the car.
After the blower, the boys installed a water/methanol port-injection kit from Snow Performance. This acted as an extra layer of safety by decreasing the chance of the motor grenading, especially during hot summers at altitude in the Rocky Mountain region. It also helped clean the carbon buildup that commonly clogs the FSI intake manifold as well, since the meth injection essentially steam-cleaned the valves.
Before all the work, the RS4 threw down 285whp on a SuperFlow dyno. A little low compared to Audi’s advertising, but Matt had to factor in the altitude of Colorado. After the upgrades, the RS4 dynoed just over 400whp. The sedan also dialed in a 0-60mph in 3.2sec compared to the manufacturer’s 4.2sec rating.
When you’re in the car it’s ungodly. It basically gives you a boner. It has consistent and endless horsepower. It’s definitely a car that will get you in a lot of trouble, explained Matt.
In case you thought the factory 365mm front and 324mm rear brakes were enough, you thought wrong. The new power warranted a brake system with more bite, so Matt waited for StopTech’s solution. The first RS4 big-brake kit was installed using 380mm and 355mm rotors with six- and four-piston calipers respectively. It was a night and day difference. It’ll put your eyeballs right into the windshield, he confirmed.
Sheltering the big brakes were a set of lightweight forged wheels from HRE. Measuring 20x10" all-round, the rollers were finished in brushed aluminum to match the window trim.
The interior followed the same functional yet fashionable theme with a steering wheel and front seats from Germany. The more ergonomic leather chairs were disassembled and painted to match the color of the car. For safety, Schroth four-point harnesses secure the driver and passenger.
The rest of the interior was genius. If you don’t know what you’re looking at, you’d never know, Matt smiled. This was because every modification looked either OEM or stealth. For example, the water/meth controller was hidden in the ashtray. You can shut it and hide it. I didn’t want to take away from the RS4 interior by having buttons and switches everywhere.
This was also the case with the Valentine One radar detector, which was cleverly installed in the dash, in the original airbag light location.
Continuing, the stereo install was nothing short of awesome. Instead of being extravagant with TVs and subwoofers everywhere, the layout was simple and stealthy thanks to the handiwork of Highline Car Audio.
Two 12" Focal subs faced each other in a lit box. To save trunk space, the Mosconi amps were hidden in a compartment below the subs; however, a hidden switch reveals the amps on a motorized rack. The interior panels were also reinforced to minimize vibration. Highline even spent extra time ensuring the trim and fabrication of the trunk looked and felt like factory.
Within the driver-side trunk panel, the five-gallon water/methanol reservoir was cleverly positioned.
Another neat interior mod was a custom iPhone dock that hooks up to the Kenwood head unit in the credit card slot.
Finally there were cameras. Whenever Matt would hit the track, he could switch on an HD camera hidden in the license plate that records footage straight to a DVR.
We built one of the most unique RS4s of its kind, concluded Max. This car isn’t a show- or trailer queen. It has a full stereo install but hits the track four or five times a summer. It’s significant in the Audi community, representing a leap forward to the V8 FSI from the 2.7T.
So is this the ultimate Audi RS4? You be the judge. But without doubt, it deserves the title of supercar.
ET Tech Spec
2007 Audi RS4
Owner: Matthew Collins
Location: Aurora, CO
Occupation: M&M Auto Body appraiser
Engine: 4.2-liter V8 FSI with PES stage 2 supercharger kit, KMD carbon catch can, Snow Performance stage 3 water/methanol injection and tank, Milltek downpipes with high-flow cats, non-resonated exhaust system, powdercoated head covers
Drivetrain: six-speed manual with Stratmosphere short shifter
Brakes: 380mm front, 355mm rear StopTech rotors with six-piston front, four-piston rear calipers, stainless lines, Prospeed RS683 fluid
Suspension: Stasis Engineering coilovers with Ohlins remote-reservoir dampers, custom spring rates, Hotchkis sway bars
Wheels & Tires: 20x10" HRE 893 brushed wheels with 275/30 R20 Michelin Pilot Sport 2 tires
Exterior: European headlights with color-matched housings, painted reflectors, 3M clear bra
Interior: European RS4 steering wheel and color-matched seats, Schroth four-point harnesses
Audio/Visual: Kenwood DNX-9140 double-DIN head unit, Focal 165KRX2 front, 165CVX rear speakers, Mosconi AS200.4 and AS 300.2 amps, two 12" Focal 72KX subs, CAMP2 real-time engine monitoring system, front and rear cameras, motorized iPod dock and amp rack
Thanks: Pearl, Aaron Marshall, Max Gerson and Scott Simpson at 3Zero3 Motorsports, Highline Car Audio, Travis and Eric