A native of Colorado, Junior Kaiser grew up in the Washington Park area of Denver. He attended his first drag race in 1955, at age 16, at Lowry Air Force Base. Like many, he was first a street racer cruising the streets and drive-ins looking to take on anyone with his Henry J powered by a V-8 Chevy. After his brother Jerry totaled the Henry J, he took its engine and put it in a 1927 Model T Coupe. In 1958, he built a top fuel dragster powered by a 389 cubic inch Pontiac engine.

Junior and his dragster showed up at Continental Divide Raceway in 1960 and won a top eliminator title defeating Hall of Famer Roy Golightly at a speed of 134 miles per hour. He continued running top fuel at CDR before moving to California. With the help of his brother, he raced at all top California drag strips running most every weekend. Returning to Colorado several years later, they put a GMC 671 super charger on a Pontiac engine in their top fuel car. Junior became one of three Colorado drivers to go over 150 miles per hour in 1962. Junior opened his own high performance engine machine shop, Kaiser Enterprises, Hi Pro Engines. It is now owned and operated by his son, Troy, and his daughter-in-law.

In collaboration with Mike Collins, Mike Widner and Mark Williams, he developed a rear engine top fuel car which the Kaiser brothers ran for over a decade. When they ran the car at the NHRA Winter Nationals, one of the drivers looked over their car from one end to the other. That driver, Don Garlets, came out with his own rear-engine car a few months later. Behind the wheel of the Kaiser Brothers top fuel car, Junior won the NHRA Division 5 Championship in 1980 and ’82. He was also ranked ninth in the country in 1982. Junior closed out his driving career partnering with Bill Rice, before retiring at age 57 in 1996