Hyundai has revealed its engineering teams have attempted to set new land speed records with the Nexo and Sonata Hybrid at the Bonneville Salt Flats on September 25th.

The vehicles were driven by senior powertrain engineer Dean Schlingmann and were modified for the attempt.

The Nexo attempted a land speed record for the hydrogen fuel cell category of 106.160 mph (170.848 km/h). It was lightly modified as the only exterior changes were the installation of a custom wrap and a “high-speed under-bumper aero valence.”

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The crossover was also outfitted with an assortment of safety features including an FIA-approved chromoly roll cage and a Sparco ERGO safety seat with a six-point harness. Other safety related items included window and arm restraint nets as well as a fire suppression system.

Likewise, the Sonata Hybrid attempted a land speed record for the gas electric hybrid category of 164.669 mph (265.009 km/h). However, the vehicle was extensively modified as it featured a host of upgrades.

Starting under the hood, the engine was equipped with a custom exhaust header and a bespoke 3 inch (76 mm) exhaust system from Injen Technology. The model was also outfited with a Nitrous Express Maximizer EZ controller, dual nitrous tanks and a “wet” fuel rail solenoid package. The car also used race fuel and run custom powertrain software.

The modifications don’t end there as the team also installed a strut, shock and spring package from KW Suspensions and a high-performance braking system. The model was also equipped with Vision Rally 55 race wheels that were wrapped in Goodyear Eagle land speed tires and covered by aerodynamic moon discs.

Lastly, engineers installed many of the same safety features as used on the Nexo. However, given the higher speeds, they also added a parachute.

The land speed record vehicles will be shown at SEMA next month and their records are still pending approval.