Chevrolet has had its appeal against IndyCar's ruling in the turbocharged controversy denied.
Last month the series had allowed Honda - which uses a single turbocharger unlike rival Chevrolet's twin layout - to modify its compressor cover in the interests of parity. Chevrolet objected to the decision, and after IndyCar rejected its protest, opted to appeal the decision. That has now been dismissed by Justice Theodore R Boehm, who was appointed to hear the case.
An IndyCar statement said: "Retired Indiana Supreme Court Justice Theodore R Boehm denied an appeal filed on April 30 and upheld IndyCar's decision to approve use of a 0.71 A/R compressor cover for the single turbocharger.
"Justice Boehm conducted the appeal hearing on May 9 in Indianapolis. Pursuant to Rule 13.11, the appeal decision is final and binding."
Practice for the IndyCar Series' Indianapolis 500 showpiece begins next week.