The 1963 split window Corvette is often cited as the epitome of Corvette design. Sure, it was difficult to back up, and it wasn’t the most powerful Corvette ever built either, but it has a number of fans. Most of these ’63 Corvettes have been restored to better-than-new quality, but at least one found its way to the drag strip.

Up on eBay is a very special ’63 split window, appropriately named “Split Personality” has an important secret under its hood; the very first pre-production Corvette Z06 engine.

According to the seller, the Z06 engine was purchased to be part of a project for Hot Rod magazine that never materialized (though we wonder what they were planning). This car is extremely well known and has appeared in numerous magazines and online publications before, so the details are well known and we won’t rehash too much. Suffice to say, the engine has been beefed up, making around 700 horsepower, a healthy increase from the stock 505 ponies. The engine is backed up by a five-speed transmission, and with the air conditioning running this Corvette gets about 20 mpg.

Yes, despite those huge slicks and that aggressive stance, this car is street legal. The stance was accomplished by replacing the stock control arms with custom tubular arms, and out back is a narrowed 9” rear end on a custom frame. As the license plate says, this is “1BAD63,” and with a Buy It Now price of $125,000, it isn’t even the most expensive split window money can buy, despite all the custom work.