The wider fenders gave the team more room to maneuver, so they opted for a generous 20x10.5" front and 20x11" rear. With TAG's new premises next door to HRE, the guys came over to check the measurements before machining a set of P104 wheels with a 37mm offset.
"The design was close to the stock RS4 wheels, but with an aftermarket twist," Alex told us." On the S4, the biggest we'd fitted was 20x10" ET36 with 255/30 tires, but for this car we were able to fit 295/25s all round; the wider rear wheels allowing the rear tires to be stretched slightly, reducing the height of the sidewall and gaining some extra clearance," he explained.
The car would remain on its KW DDC suspension with HLS nose-lift, since it's about as advanced as you can buy right now. TAG had integrated the DDC controls into the console, sitting opposite the new RS4 Stop/Start button that was fitted.
The only other interior upgrade was an AWE boost gauge, although Dennis had planned RS4 bucket seats and even its carbon-ceramic brakes, but with the project going over budget during the build stage, these additions are on hold.
Returning to the suspension, Dennis had previously fitted EuroCode sway bars and its Alu Kreuz drivetrain stabilizer, both of which were retained for the makeover. He also kept the StopTech ST-60 big brake kit with six-piston front calipers and 380mm rotors.
In the engine department, the supercharged 3.0L V6 TFSI motor had initially been uprated with GIAC software, an AWE Tuning pulley, intake and heat exchanger.
For round two, GIAC would contribute a more aggressive program because Supersprint had supplied the first example of its new long-tube headers and full exhaust system. This was finished with genuine RS4 tips to complete the makeover. And while it might not match the 450hp of the original car's 4.2L V8, you might be surprised at how fast a modified S4 can be...
Speaking to Dennis, he was predictably excited to own such a unique vehicle. He's still entertained by the online speculation whenever somebody posts a photo of it, imagining they've scooped a spy shot, but generally he can slip under the radar.
"Leaving the car in its original white meant it doesn't always get noticed at first. Despite all the work, the car is a sleeper because the RS styling is more discreet than some of its competitors. But it always gets a great reception once people realize what it is," he laughed.
In addition to the bodywork, the new engine mods also made a dramatic impact on the driving experience. "The car is now significantly faster. With the exhaust headers and updated software it pulls so much harder and is a lot more fun to drive," he confirmed.
"We actually helped Supersprint develop the headers. They sent us a prototype but it was much too raspy, so we helped them tune the sound. It's now more subdued at the bottom-end, but really wails at the top," Dennis continued.
He also confirmed the RS4 front bucket seats remain on his wishlist, although carbon fiber interior trim will probably arrive first.
He's still contemplating the carbon-ceramic brake rotors as well, but is prioritizing an upgrade for the stock rear brakes.
"The project isn't over by any means," Dennis told us. "We're still looking at what we can do in the future, but first I'm planning to get out and really enjoy the car."
2013 Audi S4
Engine 3.0L V6 24v TFSI supercharged with GIAC stage 2 software, AWE Tuning stage 2 pulley, S-Flo intake, carbon air box, heat exchanger and coolant reservoir, Supersprint long-tube headers and exhaust system, OEM RS4 exhaust tips
Drivetrain seven-speed Audi S tronic dual-clutch transmission with GIAC software, quattro AWD
Brakes StopTech ST-60 BBK with six-piston calipers in Ibis White, 380mm rotors, StopTech pads r, braided lines f&r
Suspension KW DDC coilovers with W-LAN kit for iPhone control, KW Hydraulic Lift System, EuroCode Tuning sway bars and Alu Kreuz drivetrain stabilizer
Wheels & Tires 21x10.5" f, 21x11" r HRE P104 wheels in dark tinted brushed finish, 295/25 R21 Pirelli P Zero Nero tires
Exterior OEM Audi RS4 front bumper, fenders, grille (in black), side skirts, door sills, rear doors and handles, rear quarter panels, gas door and rear bumper (blendeded to S4 bumper), European-spec headlights, S4 trunk spoiler, trim painted gloss black, car repainted Ibis White
Interior AWE Tuning boost gauge, RS4 Start/Stop button, KW DDC buttons
Thanks TAG Motorsports (tagmotorsports.com)