In 1989 there would have only been one thing better than owning a Corvette; owning a Callaway Sledgehammer Corvette. Though only one record breaker was made it revolutionized what the world would think of the American icon and made it a true force to be reckoned with thanks to the hard work and dedication of all those who worked at Callaway Cars Inc.
What was known at the time to be the “Top Gun” project had the Callaway crew set out to take an ordinary C4 Corvette coupe and mold it into a car that was capable of doing over 250 miles per hour and still be efficient enough to be a daily driver. That meant that the super Vette would have to be built to be able to drive to and from the race track and not just on the race track itself.
What was crucial to the goal of breaking 250 miles per hour was of course aerodynamics and airflow. Callaway answered that challenge by going out and hiring the best in aerodynamics and commissioned Paul Deutshman of Deutshman Design to rework the design of both the outside aerodynamics and also to work on the air flow itself as that would be crucial to feeding the twin turbos that were planned to go into the Sledgehammer.
The engine of the Sledgehammer Corvette was intricate to say the least and was built by hand by John Lingenfelter and some of the top engineers that Calloway had in its arsenal. Special considerations and modifications had to be made in order to fit in the twin turbos and also to find a place for the special air box that would feed those turbos. The result was a shifting of major engine parts and a cutting of the actual frame so that everything would fit into the tight space that a Corvette allowed under the hood.
The end result saw the twin turbo engine put out an overall 898 horsepower with an unheard of 772 foot pounds of torque to go with it. When it was all complete the time came to test the Sledgehammer Corvette and see if it was indeed capable of putting up speeds that were expected of it.
At first the testing didn’t go quite as planned at the Transport Research Center in Ohio. While the car was exceeding the 200 mile per hour mark with little effort the goal of 250 was still somewhat off. When the test track officials found out that the speed of 250 miles per hour was not only wished for, but expected they cast their doubts and some even snickered.
That only made the Callaway team work harder and their efforts would be rewarded. On October 19, 1989 the Sledgehammer Corvette took to the track and hit about 248 miles per hour on one of its final runs. The test track officials gave the team just one more opportunity before they would close down the track for the day and the Sledgehammer Corvette piloted by John Lingenfelter would prove the critics wrong as it blazed down the track at a top speed of 254.76 miles per hour.
As if that were not impressive enough, the Sledgehammer Corvette was then driven back to its home without faltering a bit. All and all it gave a true testimonial to the work of Callaway and the durability of the Corvette itself. While it was anything but stock, this ultra fast Corvette set the stage for other projects to be completed by Callaway and GM and showed the world that it was possible for an American car to go as fast as the million dollar plus imports.