The entrepreneurial endeavor commonly known as “The American Dream” comes in all shapes and sizes. Many of the greatest automotive incarnations have either come out of someone’s garage or from smaller shops like Carol Stream, Illinois’ very own Koza Performance. But unlike loads of other little guys, shop owner John Koza has maintained an approach to precision, speed, and quality that surpasses the masses. These and many more attributes can be found encapsulated within his world record-holding Chevrolet SS Sedan, bringing much-needed recognition to a car that no one wanted.

Photos by: Mike Pryka

Koza originally purchased this 2014 Chevrolet SS Sedan because he needed a family car. It has since become one of the fastest four-door automobiles ever built.

Enthusiasts never really got into the Chevy SS Sedan for a multitude of reasons. It was heavy, featured cheap interior materials in certain areas, way too much bling in others, cost damn near $50,000 in base form, and was entirely too bland-looking to be labeled as a “sport sedan.” Whatever the reason, the rebadged Holden Commodore never really caught on here in America like it did over in Australia, thus leading to the SS Sedan’s discontinuation just a few short years after its release. This was good news for Koza, a man who translated the words “unwanted and cheaply made” to “easily obtainable and affordable.”

A fully built Dart engine, complete with a Koza Performance twin-turbo kit gives this sedan an earth-shaking 1,750-horsepower and 1,490 foot-pounds of torque.

Surprisingly, the 32 year-old shop owner and chief mechanic never considered owning an SS Sedan, nor did he ever imagine modifying one to the point where it could be labeled as a world record-setter. But when a friend asked if he could borrow his truck for a day in exchange for the keys to the GM sleeper sedan, the SS quickly shot to the top of Koza’s must-have list. He was not only impressed beyond belief by the performance packed within the unassuming sedan, but equally amused by how oblivious people were to the power it possessed. News of his wife’s pregnancy only strengthened Koza’s resolve to own an SS Sedan, and thus, a plan was put in place to turn one into the ultimate family commuter car.

Come 2018, a 2014 model of the Chevy SS Sedan had been sourced via the local Chevy dealership that supplies Koza’s shop with all of its OEM components. Like kids with a new LEGO kit, the team ripped into the sleeper sedan, only to find that they had just opened a 2-ton can of worms. All of the insane Corvette action that had rolled out of Koza Performance’s bay doors had not prepared he and his crew for the challenges they would encounter with this unloved GM machine.

A carbon-fiber rear drag spoiler from Angry Aero is but one of several purpose-built exterior modifications made to this insanely quick sedan.

Your average racer or gearhead would not waste their time building or racing a 4,000-lb family sedan.

Having limited access to what Koza calls “race application parts” forced the shop to undertake an inordinate amount of testing, breaking, fixing, and head-scratching in order for the vehicle to reach extreme speeds.

Although the car’s 415-horsepower, 6.2-liter LS3 V8 was a huge selling point, there were some unappealing attributes that made this sedan a real challenge to build. According to Koza, this project “required extreme patience,” not just due to the appalling lack of aftermarket support, but because of the weaknesses found within the chassis itself, as well. Not only is the SS Sedan heavy as all hell, but the car’s IRS rear suspension and drivetrain were a major hindrance.

A dual, BorgWarner turbo layout and a laundry list of race-specific mods have turned this sedan into a world record-setter.

Very little is left stock in the engine bay, with the most recent Dart motor upping the ante via the introduction of a custom top-mounted, air-to-water intercooler from Shearer Fabrications.

As for speed, that comes from a fully honed and filled 433 cubic-inch Dart engine, which receives forced-induction power from a custom Koza Performance twin-turbo kit sporting dual BorgWarner snails. Equipped with numerous fueling and air induction upgrades, a custom Koza tune, and accompanied by a fully loaded three-speed TH400 transmission, the world’s fastest Chevy SS Sedan is a force to be reckoned with, regardless of whether you approve of it or not.

Although the Chevy SS Sedan currently relies upon 24 psi of boost pressure, there is talk of upwards of 40 psi making its way into this system later this year.

While we’ll let you sift through the lengthy list of mods below at your leisure, there is one import lesson to be learned here: setting goals matters. For as frustrating as this car was to build, John Koza’s ability to set goals for himself and this vehicle are what made it all possible.

Creature comforts on this car are almost completely non-existent, thus earning it a dragstrip-exclusive status.

Koza’s goals were simple: source a Chevy SS Sedan, design and build a turbo kit, be the first SS in the 8-second ¼-mile club, become the fastest SS Sedan in the world, and then break into the 7-second territory in the chunky family sedan. All of these things were achieved in surprisingly swift fashion, leaving ample room for Koza to focus on tackling his next big challenge: securing a sub 7.50-second pass and a 200 mph trap speed.

You will not find a more fun family sedan with the same amount of luxury the SS Sedan provides.

In order to get to the level you see today, Koza Performance’s Chevrolet SS Sedan had to destroy three engines and numerous drivetrain components before its creators were finally able to find a balanced setup.

Koza explains that while he never really had aspirations of owning the world’s fastest Chevy SS Sedan, his background did prepare him for this venture. What began with wrenching on cars in eighth grade eventually turned into a 15-year-long career, which humbly began with a porter/lube tech position at a local Chevy dealership. Prior to opening Koza Performance, John hopped from one privately-owned company to another, until a job at Firestone taught him the importance of busting ass. This expeditious work ethic earns Koza Performance praise for its extremely quick turn-around times — a bit of a rarity in the aftermarket arena.

A 417 Motorsports billet lower/Shearer Fabrications upper air-to-water intake manifold setup ensures that ample amounts of cooled air reach the CNC-honed V8.

Candidly speaking, Koza also has a bit of a love/hate relationship with custom cars. He despises the tedium, setbacks, dangers, flakiness, and BS typically associated with modifying other people’s automobiles. However, he also loves it when everything comes together, project goals are met in a timely fashion, and a customer leaves the shop smiling ear-to-ear.

There’s no better feeling out there than reaching the goals we push for… [like] teaching my 2 year-old son every part on the car. He will bring you over to the car and point out/name every part possible, especially his favorite… the turbos.

Last year’s old setup resulted in a record-setting 7.96-second time at 183 mph. Koza Performance is expecting even more impressive numbers this year now that the car’s radiator has been deleted and it’s fuel cell has been reduced in size.

As for the the dragstrip, Koza tells me that this part of his career provides a different sort of pleasure. While the adrenaline rush experienced while racing remains an unfathomable addiction, meeting people from all walks of life who share this same passion is what kept him coming back. Doubling as a way in which he can promote his shop, drag racing has become a crucial part of this SS Sedan’s existence. So if you want to see the Koza Performance Chevy SS Sedan hauling ass down the strip, you should attend some events this year, like Anarchy No Prep, G8/SS Extravaganza, the Holden Nationals, Street Car Takeover, and Lights Out.

“We will run in any event/class that will allow us to,” Koza says. “Last year we took runner-up in an X275 no-prep class and are ready this year to try and capture that ‘W.'”

So what does it feel like, manning the helm of the world’s fastest Chevy SS Sedan? Koza laughs, and explains that nautically speaking, it “drives like a big old boat.” Fortunately, due to its numerous suspension and chassis mods, the SS handles alright in the corners, just as long as you don’t mash the throttle vigorously. Push the car too hard, and John says that the rear end will break out faster than you can say “Coronavirus,” thus making it damn near possible to control. Slowing down at speed traps when going over 180 mph can also be a bit of a challenge, even with the car’s obvious brake upgrades.

A look at the fuel tank setup in the street-legal Koza Performance Chevrolet SS Sedan.

Despite its original purpose, you won’t find this record-setting machine on the streets anytime soon. Having served double-duty as a daily-driven grocery-getter and weekend track warrior for the better part of the past two years, the twin-turbo Chevy SS has officially retired from on-road anarchy. This is due to several reasons, with the primary one being that the radiator in the car has been removed to save weight this season and that the new fuel cell is far smaller than the old one in order to shave-off a few additional pounds.

A stock dash, carpet, and door panels are some of the only original parts left on this gutted chassis.

As for future goals for Koza Performance and its owner, word on the track is they have already built a second Chevy SS Sedan. This street-legal vehicle currently holds the title as the third fastest SS in the world, and according to Koza, is regularly driven both to and from the track. With a 9.1-second record time at  151 mph, this 100-percent factory accessorized/optioned street car makes around 1,120 wheel-horsepower, numbers that are achieved with the assistance of a Koza Performance single turbo kit.

The latest, street-legal Chevrolet SS Sedan to come out of Koza Performance is a weekend warrior street car with around 1,120-horsepower. Opting for a round of Koza’s race-proven products provides plenty of performance action for anyone looking to grab a gallon of milk in a hurry before picking the kids up at the neighborhood pool party.

So if you’re interested in building your own Chevy SS Sedan, John Koza has a few useful tips. While setting achievable goals should always be first, committing to either a street or strip approach is best. The numerous OEM handicaps found within these vehicles, and limited access to aftermarket options make the SS quite pricey to build, so choosing a mild or wild approach really depends upon how fat your wallet feels.

Daily commuting duties pretty much went out the window when things like a full Wisconsin Race Cars 25.5-point cage were installed on John Koza’s 2014 Chevrolet SS Sedan.

We compete with cars way beyond our league and give them a run for their money. Not to mention we will sometimes race with the baby seat in the back.