Produced from 1958 to 1975, the Biscayne is nowhere near as iconic as Chevrolet’s other full-size cars from the era. But even though it’s been overshadowed by the Impala, Caprice, and Bel Air, the Biscayne was just as appealing in terms of performance. This 1965 example shows why.

The mid-1960s saw Chevrolet introduce the fourth-gen Biscayne. And much like the Impala, the Biscayne grew larger and looked sportier, especially in two-door sedan form. But more importantly, 1965 brought a brand-new V8 engine under the hood. I’m talking about the L78, the big block some of you may know as the Turbo-Jet.

What made the L78 special, you ask? Well, this 396-cubic-inch (6.5-liter) was rated at a whopping 425 horsepower and 415 pound-feet (563 Nm) of torque, figures that made it Chevrolet’s most powerful mill through 1969. The Turbo-Jet is actually better known for its presence in cars like the Chevelle, El Camino, and Camaro, all of which were offered with the 396 from 1966 to 1970.

However, the L78 made its debut in Chevrolet’s trio of full-size cars and the Corvette in 1965. And this is the only year when these cars were available with this specific big-block V8. And with only 1,838 full-size cars ordered with the L78, Biscaynes fitted with this mill are rare and hard to find.

There’s no breakdown for nameplates and body styles, but experts agree that most of the 1,838 L78 cars were of the Impala SS variety. This means that Chevy might have sold fewer than 100 Biscaynes with the 396. This plain-looking two-door sedan is one of them.

So yeah, don’t let that unassuming exterior fool you. This is not your grandpa’s Biscayne, but a full-fledged muscle car that spins its rear wheels to the tune of 425 horsepower. It’s a survivor, too, even though the 396 L78 under the hood is not a numbers-matching unit.

But there’s no need to be disappointed. The owner of this car made sure that the replacement 396 L78 is a date-correct mill. In layman’s terms, the engine was taken out from an identical 1965 Biscayne. And since he’s been restoring Camaros for about 30 years, the transplant is as clean as they get. In addition, he replaced the original three-speed with a four-speed manual.

And yes, while the worn-out paint suggests this Biscayne is a tired daily driver, the two-door is just as snappy and aggressive as it was when it left the factory more than 50 years ago. The front bench seat also helps this classic achieve that misleading sleeper look. This is one Biscayne you wouldn’t want to drag race unless you’re driving a rare L78-equipped Chevrolet Corvette. Check it out in the video below.