Headlining the enhancements is the use of a single-stage nitrous injection system, meaning this record can't be claimed as a pure petrol-electric hybrid achievement.
Still, it does look the goods. Along with a nitrous system, the "race-prepared" Ioniq also features low-restriction intake and exhaust systems (with retained catalyst), along with uninhibited engine, transmission and hybrid ECU calibrations set-up specifically for this record run.
Useless components like interior features, air-conditioning and ancillary accessories were dropped, while underbody and air-dam modifications were added. The hybrid Ioniq was also given the all-electric Ioniq variant's front grille and valance for improved aero performance.
The tweaks are rounded out with a fully-integrated high-strength safety cage from Bisimoto, a Sparco racing seat and six-point safety harness, and an onboard fire suppression system with battery disconnects and a parachute.
All of this came together to give the Ioniq hybrid prototype an FIA-approved "production-based hybrid vehicle" land speed record of 157.825mph (254km/h), with a peak exit speed of 258.6km/h.
The regular everyday Ioniq will come to Australia next year, with the plug-in hybrid variant (which sits between the hybrid and all-electric models) the likely starter.
For more on the Ioniq, see our earlier coverage at the links below.
MORE: Hyundai Ioniq plug-in hybrid to get Prime position
MORE: Hyundai Ioniq PHEV will go unchallenged in Australia
MORE: Hyundai Ioniq plug-in hybrid 'most appealing' for Australia
MORE: all Ioniq news coverage
MORE: Hyundai news and reviews