There is no universally agreed upon criteria for exactly what constitutes a muscle car, but the term typically refers to mid or large sized, two door automobiles with powerful engines. Most muscle car restoration focuses on earlier model vehicles that can date anywhere from the late 1940s to the early 1970s. Restoration of these vehicles typically involves returning the body, interior, and powertrain to a good state of repair. Hobbyists often engage in muscle car restoration, though there are also professionals that focus on different aspects of the process such as body repair, engine rebuilding, and upholstery work.
A muscle car restoration can involve anything from some light body and engine work to a complete rebuild from the frame up. If a vehicle has a solid frame that is free from rust or accident damage, it may be a candidate for restoration. Body, powertrain, and interior repairs are typically different parts of the process, and some vehicles require attention in all three areas while others only have issues in one or two. If an enthusiast enjoys tinkering with engines, he may choose to get the vehicle into running condition and then hire professionals to do body or interior work. Others might prefer to source every part and do all of the repairs personally.
Many muscle car restoration projects involve classic or antique cars. These terms can vary slightly in the model years they describe, though classic cars are often considered to be twenty or more years old. This advanced age can make it difficult to locate brand new, original equipment (OE) parts for use in a muscle car restoration. Some enthusiasts prefer OE, so they may end up sourcing parts from junk yards or old dealer stock. Others might be happy to use replica body, trim, and engine components that are often readily available for popular makes and models.
The muscle car restoration process will often involve an effort to restore the vehicle to its original condition without making any unnecessary modifications. This may result in restored antique or classic muscle cars that lack modern safety devices, such as seat belts. Certain classic and antique vehicles may also have longer stopping distances, be more difficult to steer, or generally harder to drive than their modern counterparts. This can be compounded further due to the fact that muscle cars tend to have such powerful engines. Some jurisdictions allow people to operate classic or antique cars without modern safety features, though there may be restrictions on how often or far they can be driven.