Following a lengthy hearing on Thursday before a three-person panel, the IndyCar Series has rejected Chevrolet's protest against Honda's planned turbocharger modifications the manufacturer wanted to introduce.

Honda had been granted permission by the series' governing body to introduce a new housing for the upcoming race in Brazil to which Chevrolet had objected.

Honda engine. (Photo: IndyCar)

The decision was made as to achieve parity between the alternative turbo layouts. - despite this promise not being formally enshrined within the regulations.

But after a lengthy hearing on Thursday, IndyCar ruled that Honda could go ahead with its changes.

Honda welcomed the decision, saying in a statement that it would level the playing field. "The new compressor cover helps to offset a demonstrable performance disadvantage between single- and twin-turbocharged IndyCar Series engines."

So far this season, Chevrolet has won all three rounds held since the new technical package came into effect.