While previous ARXs were evolutions, the fourth-generation Honda ARX-04b LMP2 car is a clean sheet design that, as a result, looks radically different from its predecessors. Aside from the obvious addition of a roof, HPD worked with Wirth Research to shape the 04b to be as aerodynamically efficient as possible. It also gets a new ACO-mandated drive-by-wire throttle system and cost-capped chassis construction. Power comes from the same twin-turbo 2.8-liter HR28TT that powers the current ARX-03b LMP2 cars but now features a new fresh-air valve system that reduces turbo lag and improves efficiency.
Honda Racing Development’s ARX racers have been slugging it out in prototype classes around the world for several years now. Since 2007, three generations (and several iterations within each generation) have won races in both LMP1 and LMP2 classes. The ARX-04b will be eligible for competition next season in the WEC LMP2 and USCC Prototype classes.