The accident happened outside the Moody Cow in Apperley Bridge, near Bradford, on Monday afternoon after Mr Tordoff had pulled his car into the pub's car park to turn around.
Jack Tordoff, who is still the chairman of the firm he founded in 1946, escaped the crash with minor injuries.
The 83-year-old was driving the Porsche 4x4 when witnesses saw it clip a bollard as it left the pub car park and overturn.
JCT600 are the shirt sponsors of Bradford City and employ more than 2,000 people across 50 sites in the UK.
The company's headquarters are at Apperley Manor in Apperley Bridge. Tordoff, who trained as a mechanic, has held a Porsche sales franchise since 1967.
He lives in Rawdon and has a holiday home in Barbados. As a young man he was a keen rally driver, and he also has a pilot's licence, and keeps a private Cessna light aircraft at Leeds Bradford Airport.
A spokesperson for JCT600 said:
"JCT600 has confirmed that founder and chairman, Jack Tordoff, was involved in a car accident in Apperley Bridge on Monday afternoon.
"Only Mr Tordoff’s vehicle was involved and, fortunately, he only sustained minor injuries."
Image credit: Guzelian