How This ’90s Audi Became The World’s Fastest Sedan

To declare that something you built is the absolute fastest of its kind is an incredible feat. While there are a lot of people and carmakers building fast four-doors, only one sedan can hold the crown as the world’s fastest. Since 2012, it’s been a humble Audi from the 1990s.

The car is the brainchild of one Jeff Gerner, the founder of a firm called Four Rings Motorsports. Based on a 1993 Audi S4, it looks fairly tame from most angles; the only thing that really gives it away is the livery, some missing mirrors, and a parachute on the back. How did a blocky mid-range Audi sport sedan manage to snag one of the most impressive land speed records on the books? As it turns out, the car’s story is as interesting as the record it holds.

Gerner is a lifelong gearhead, telling Summit Racing back in August he was building V8s for his friends in high school by the time he was 17 years old. He eventually got into drag racing, but briefly hung up his firesuit to work as a fleet manager to support his growing family. Gerner couldn’t stay away from the competitive scene for long, though, buying a Honda CRX Si in 1988 to go autocrossing.

What followed was a decade of parking lot time attack behind the wheel of the CRX. Gerner was pretty serious about it, traveling to Kansas in 1994 to compete in the SCCA’s Solo II Nationals event (he finished 10th out of 25 entries in C Street Prepared class, according to SCCA archives).

But by 1999, Gerner wanted more speed. So he bought a used ’94 Audi S4 and built it up for track days. The now-defunct Eurotuner Magazine interviewed Gerner about the car in 2008, where they detailed the pretty serious mods:

Right away he performed heart surgery, yanking out the factory KKK K24 turbocharger and exhaust manifold. In their place, a ported and coated manifold with a turbo from the S4’s European brother, the 315hp Audi RS2, were installed to the port-matched, polished and multi-angle cut cylinder head, which Jeff did himself. To further help flow, Jeff also ported the stock intake manifold, matching it to the head’s intake ports.

The new turbo exhales through an 034 Motorsport downpipe and 3″ mandrel-bent exhaust with a racing cat up front. The system is audibly tuned to a harmonious, deep rumble with an Ultra Flow stainless center resonator and an Aero Exhaust “turbine” muffler in the rear. Boost is controlled by ECU through the external factory wastegate, but with a stiff 1.9bar (27.6psi) spring fitted, the wastegate stays firmly closed during spool-up for maximum response. Henceforth, there is no low-boost setting.

For the next eight years, Gerner would participate in track day events “all over the country” behind the wheel of this S4, while also using it as a daily driver. Then he saw the 2005 feature film The World’s Fastest Indian, which tells the true story of how New Zealander Burt Munro brought his land speed racing bike to America to compete at Bonneville, setting a record in the process. From the Summit Racing interview:

In 2006 or 2007, I can’t remember what year it was, we saw The World’s Fastest Indian. That wonderful movie. And as I’ve said many times, if Burt Munro can get there from New Zealand, I can get there from Kansas City. The movie motivated me, and because I knew what the Audi S4 sedan was, how tank-built and solid they are, and all-wheel drive on the salt. I knew it would be the perfect car for me to build.

I worked on the car six to seven hours a day for nine months. I did all the work myself, from stripping the car and fabricating the roll cage to sanding and prepping the body for paint. Then came the engine, drive-line and suspension work.

[…]

[P]reparing an engine to attain and survive this level of performance takes an immense amount of time. The cylinder head alone, for porting, valve work and conversion from hydraulic to solid cam followers took in excess of eighty hours. Then there were big mods to the fuel delivery system, installation of fire suppression, driver safety and parachute systems etc.

The 20-valve turbocharged inline-five was comprehensively reworked with custom parts. Among the long list of mods is a custom billet crankshaft, custom pistons, and a custom dry-sump oil pan. Everything inside the engine is essentially new or heavily upgraded, including the turbocharger, which was sourced from Borg Warner. The five-speed manual was swapped out for a six-speed unit with longer gears, while the rear diff was also swapped out for a custom unit.

The result of all those engine mods was huge power. These five-cylinders are known for being able to hold lots of horses, and Gerner’s build is no different. A dyno run resulted in 1,155 horsepower and 705 pound-feet of torque to the wheels, which is pretty impressive, even by modern supercar standards. Video of the run is equally as cool:

There’s also the suspension, which is far more important than you think for a car that doesn’t need to turn. From that Quattroworld interview:

The front to rear attitude of the body as it rests on the suspension is very important to speed, stability and safety. We run the car three quarters of an inch higher in the rear for added stability and rear wheel traction. This difference in front to rear ride height, combined with the shape of the S4’s body and under trays, produces a slight wedge under the car opening to the rear. This creates down-force and aids with getting the engine’s huge exhaust volume passed beneath the car without the car being lifted by the exhaust pressure.

All of that work paid off. In 2011, Gerner went 242 mph during Bonneville Speed Week in Utah at the Salt Flats, solidifying his S4 as the fastest sedan on the planet. Then he came back again in 2012, besting his previous run and hitting 250.009 mph in 2012. To claim the record, Gerner also had to attempt a run in the opposite direction (to account for wind direction). On the second run, he hit 223.189 mph, for an average of 236.599 mph—a record for sedans that still stands today. eGarage was on the scene and covered the record-breaking run as it happened:

Then there’s the 250-mph run itself, which looks fairly drama-free, aside from a wiggle at the top of 4th gear that caused Gerner to lift off for a split second. The moment he pulled the parachute also unsettled the car quite a bit, with Gerner having to saw at the wheel to keep the nose pointed forward.

Despite being a fairly square-shaped Audi sedan, Gerner’s S4 blows every production four-door out of the water when it comes to fastest speed. The fastest four-door on sale right now is the Xiaomi SU7 Ultra, which has a manufacturer-claimed top speed of 217 mph. The fastest sedan you can buy in America, meanwhile, is the Lucid Air Sapphire, which can go “just” 205 mph.

If Gerner’s story inspires you (or you just love going really fast in cars with four doors), you’re in luck. The record-holding S4 is currently up for sale. Gerner attempted to sell the car on Cars & Bids, where it was bid to $33,000, but didn’t sell. Now, it’s up for grabs on RaceCarsForYou.com, a classifieds site for competition vehicles. Gerner is asking just $65,000.

If you want to beat this Audi, you’ll have to venture further into the exotic space with cars like the Bugatti Veyron 16.4 (top speed: 254 mph) and the Rimac Nevera (top speed: 256 mph). Both of those cars cost well over $1 million. So if speed is truly your only goal, this S4 represents a tremendous value for money. Plus, you also get a record-holding car with an amazing story.