A 1967 Chevrolet Impala that has been stored inside for decades hides changes made under the hood.

The Chevrolet Impala from 1967 has a lot of history because it was one of the most famous cars of its time.  

Not all Impalas are driven and enjoyed, though.  

Some are left parked inside for decades, where changes happen under the hood. This Impala did the same thing.  

It was kept in a shed for 40 years and is now back with a surprise.  

Tom Smith, the owner, got the car from his grandfather, who changed the engine to a 427-cubic-inch V8 that wasn't offered on the Impala in 1967.  

The engine gives the car 385 horsepower, which makes it a real beast.