Kevin Rogers, 53, a retired machinist and a stock market dabbler from Richmond, Ill., on his pair of rare muscle cars, as told to A.J. Baime.

When people think of muscle cars, they think Camaro, Mustang, Dodge Charger. I like different cars—cars that stand out in a crowd.

My 1970 Oldsmobile 442 was known in its day as “the banker’s muscle...