Glass-fibre reinforced “Zytel” Plus 95G35 from DuPont (Wilmington, Delaware / USA; www.dupont.com) has been specified for the resonator for the BMW "i8" hybrid sports car. The resonator is tuned to reduce the typical high-frequency air intake sound to a lower level, improving the driving experience.

The material is a high performance PA that provides improved long-term resistance to high temperatures and aggressive fluids typically found in under-the-hood applications. The resonator, developed in close collaboration between BMW, DuPont Performance Materials and Mann+Hummel (Ludwigsburg / Germany; www.mann-hummel.com) has a relatively large volume, but weighs just 1.5 kg thanks to optimised wall thicknesses and the use of the high stiffness and high strength grade of the material.

Installed between the air filter and turbocharger in the rear of the i8, the resonator is part of the air management system of the sports car’s compact 1.5 litre 3-cylinder petrol engine. It has long-term resistance to temperatures from -40 °C to 190 °C as well as hot engine gases and fluids.