Not every 1960s muscle car came from the factory. This 1967 Chevrolet Yenko Super Camaro 427/450, which heads to the auction block at Barrett-Jackson's sale taking place on January 29 in Scottsdale, Arizona, was the product of an enterprising dealership.

At his Canonsburg, Pennsylvania, dealership, Don Yenko built the cars General Motors wouldn't. Shortly after the Camaro debuted for the 1967 model year, Yenko decided to stuff a 427-cubic-inch V-8 under its hood, something Chevy didn't initially offer in the Ford Mustang rival. Besides this creation, dubbed the Yenko Super Camaro, Yenko also offered tuned versions of the Chevelle and Corvair.

The car headed for auction started out as an already-rare L78-powered 1967 Camaro. It was one of just 1,138 cars to leave the factory with Chevy's 396-cubic-inch V-8, backed by a Muncie close-ratio 4-speed manual transmission.

1967 Chevrolet Yenko Super Camaro 427/450 (photo via Barrett-Jackson)

1967 Chevrolet Yenko Super Camaro 427/450 (photo via Barrett-Jackson)

However, Yenko's upgrade to the 427-cubic-inch L72 V-8 brought an increase in power, from the stock 375 to 450 hp (hence the 427/450 designation). And while this Camaro was pretty rare to begin with, it's one of just 54 documented 1967 Yenko Super Camaros, according to the listing.

In addition to the bigger engine, Yenko added a heavy-duty clutch and pressure plate, and upgraded the cooling system and suspension. All for just $677.27 in 1967 dollars.

Barrett-Jackson doesn't list pre-auction estimates, but given this car's rarity and the continuing market appetite for classic muscle cars, you can expect it to sell for serious money. The Yenko name was recently revived by New Jersey-based Specialty Vehicle Engineering for a series of modern tuned Chevys with up to 1,050 hp, but that won't diminish the appeal of the original Yenko Camaro.