The year was 1988, and America was waking up from the much-maligned malaise era of automobiles. American automakers were finally able to start building the big and powerful cars they were once known for, and a shellacked automotive aftermarket was taking the first steps of rebuilding what has become a robust and impressive empire worth billions.

Connecticut-based Callaway Cars has never been one to shy away from big-horsepower machines, and they were one of the first companies to truly push the envelope on modern car performance. Cars like the 254 MPH Callaway Sledgehammer Corvette helped cement their reputation as professional tuners, and Hemmings Auto Blog reports that this incredible machine will soon hit the auction block.

The 1988 Callaway Sledgehammer is is the road-going evolution of Callaway’s other über 80s Corvette, the 284 MPH Top Gun Corvette. Designed for better low-speed drivability and for keeping most of the factory options, like the heater and the radio, the Callaway Sledgehammer improved on every performance aspect of these late-model C4 Corvettes.

A four-bolt “Bowtie Block” housed all-forged internals and a custom camshaft, and was fed by a cutting-edge fuel injection system. A pair of large Turbonetics turbochargers helped boost power to 898 ponies and 772 pound-feet of torque, and an Aerobody bodykit helped the Sledgehammer slip through the air with minimal drag. This helped this Callaway supercar reach a top speed of 254 MPH, and when it crosses the auction block at Mecum’s Kississimme auction in January the Sledgehammer is expected to bring between $750,000 and $1 million.