Coleman is the president of Competition Cams, a world leader in valvetrain technology, and under his management the company has acquired several other businesses to make it the successful operation that it is today. He also founded the National Muscle Car Association, which is recognized as the largest national sanctioning group dedicated to street-legal vehicles.

Additionally, Coleman served on the SEMA Board of Directors for two terms and dedicated his professional time to a four-year stint as SEMA Chairman of the Board. He also served on the Joint Operating Committee for Automotive Aftermarket Industry Week (AAIW) and, at the governmental level, was elected to the White House Conference on Small Business twice. He was active in issues involving government regulations and taxation of business, and testified before the Senate Small Business Committee to encourage the reduction of regulations that impact small business.

With SEMA, Coleman was active in the U.S.-Japan Auto Parts Trade Agreement, which for the first time gave U.S. companies a fair chance to compete with product sales in Japan.