Audi RS4/RS6, Z4M Turbo and 242.5MPH S4 - Garage Projects - Eurotuner Magazine

Audi RS4/RS6
HT Motorsports, EFI Express and Advanced Technologies are still at it, swapping a RS6 motor into customer Bryan Whitmore’s ’07 RS4. While the project is awaiting a few components they’ve been busy fabricating other components.

The most recent task was to weld a new turbo-back exhaust with centrally mounted resonators. The muffler have yet to be selected, because the team wants to first hear what it sounds like before silencing the system.

The transmission returned last week with straight-cut first and second gears to enhance the RS4’s drag racing potential. With this aim, it also has a front Torsen LSD, with a Wavetrak LSD in the rear, housed in a B5 S4 long-nose casing. Connecting everything together is a custom, single-piece propshaft from The Driveshaft Shop.

The RS6 V8 now has a CAD-designed valley-mounted alternator and AC compressor as well as a low-mounted sump pump. Next, they’re planning to run oil lines for the external oil coolers on the diffs, transmission and engine.

Modifying the rear bumper support, they’ve mounted the oil coolers to utilize the RS4’s stock rear vent. Additionally, they’ll add an air scoop below the fuel cell to push air through it. The team is also wiring the engine with various black boxes and coil mounts to coincide with the arrival of the second Borg Warner turbo and ported heads.

Z4M Turbo
Trevor Chevalier from San Francisco and friend Marcus Olson turned a three-day weekend into an epic Cannonball-style road trip from Phoenix, AZ to Tampa, FL to give his ’07 BMW Z4M Roadster some turbo power.

Although Trevor’s car was at ProEFI in Phoenix getting an E85 software update, the two friends were discussing forced induction options, inspired by Olson’s 800hp Horsepower Freaks M3 turbo (et 12/11).

After locating a shop able to build the car, the pair flew to Phoenix to collect the Z4. They then smashed the pedal for a 34-hour joy ride, leaving at 10pm Friday night. Stopping once in Baton Rouge, LA to swap drivers and catch a nap, they arrived Sunday afternoon. Using Google Maps to calculate the distance and time, they forgot to add the three-hour time difference, so Trevor barely had time to toss the keys to Shawn Grawunde at Lutz Performance before they boarded a plane to make a Monday morning meeting.

Fortuately, Shawn and Trevor had already devised a plan over the phone to build a custom turbo set-up using an HPF intake manifold and twin-scroll Garrett GTX35R turbo. Jason Siebels at ProEFI would meanwhile develop a wiring harness to adapt his engine management system to the Z4, as well as a clutch and billet flywheel.

The plan is to have the Z4 pushing 700hp on E85. Of course, we’ll update you as the project progresses.

242.5mph S4
Several parts are being finalized at Four Ring Performance for Jeff Gerner’s ’93 Audi S4. The plan is to return to the Bonneville Salt Flats for another record-breaking attempt.

Last summer, Jeff reached 242.5mph, which was well above the 224mph record in the F Production Supercharged Class. However, an engine failure aborted the required second run to put Jeff in the record books.

Working towards breaking the record this year, Jeff removed the five-cylinder 20v engine and has been re-engineering it for greater reliability. One of the most vital components is the crankshaft damper, which needs to withstand torsional vibration for long periods of sustained high RPM.

For the past four months, Jeff has been working with ATI Performance Products in Maryland building a damper system. After relocating the factory oil pump, adding a front closer plate and dry sump pan, Jeff created space north of the crank to accommodate the ATI Super Damper capable of withstand 1000hp and 10,000rpm.

To put things in perspective, the stock damper only can handle 225hp at 7000rpm, so the Super Damper has a custom mounting hub with a 2" interference fit that is pressed onto the crank snout and bolted in place.

We’ll bring you more details on the final touches to the dry sump (which should soon have a new pump from Peterson Fluid Systems) as well as assembly of the block before its return to the famous salt flats.