INDYCAR announced that turbocharger boost pressure during push-to-pass use will increase from 160 kilopascals (kPa) in 2015 to 165 kPa, equating to a gain of approximately 20 horsepower in the Chevrolet and Honda 2.2-liter, twin-turbocharged V-6 engines. Normal boost pressure on road and street courses – before the overtake assist is engaged – remains at 150 kPa in 2016.
A total of approximately 60 added horsepower will now be available for push-to-pass activations during the 11 road- and street-course races in 2016, nearly doubling the on-track effect for passing over 2015.
"The Verizon IndyCar Series already boasts some of the most exciting racing anywhere," said Jay Frye, INDYCAR President of Competition and Operations. "This technological update is part of INDYCAR's ongoing initiative to enhance the overall level of competition and excitement even more. Increasing the available push-to-pass horsepower will make the system more robust and lead to additional overtaking opportunities on road and street circuits."
Push-to-pass parameters for each track – the number of pushes available and duration of each – will remain the same as in 2015.
According to Marvin Riley, INDYCAR Director of Engine Development, the push-to-pass boost pressure increase coincides with other 2016 engine updates through homologation which include the cylinder head ports and combustion chamber, fuel injectors, camshafts, pistons and connecting rods.
"These updates are part of continued open development in the manufacturer competition between Chevrolet and Honda," Riley said, "but are also needed for performance and durability when you increase the peak power of an engine."