John Rostek raced his way to five series championships with the Intermountain Racing Association, racing at tracks in Fort Collins, Cheyenne, Longmont, and Greeley in the early to mid 1950’s. He also won four Stock Car championships at Pikes Peak Speedway in Colorado Springs, and drove a Mercedes 300 SL to the Sports Car division title at the Pikes Peak Hill Climb in 1959.  He later competed in USAC stock car races across the country, and compiled a record of one victory, one pole and three top-ten finishes in the six Grand National NASCAR races he entered.