More technical details of the next-generation Honda NSX have been revealed at the SAE (Society of Automotive Engineers) World Congress in Detroit, Michigan.
The biggest news is the new Honda NSX — known again as the Acura NSX in certain markets — will feature a dry sump 3.5-litre twin-turbocharged V6 petrol engine mounted behind the passenger compartment. The V6 motor is longitudinally mounted, has a 75-degree V angle, and is fitted with both port and direct injection.
The twin-turbo V6 drives the rear wheels via a nine-speed dual-clutch automatic transmission that was developed in-house. Both these items are paired with an electric motor that “applies its torque directly to the crankshaft for higher output with immediate power delivery to the rear wheels”.
At the front, each wheel is powered by its own electric motor — a setup the company dubs ‘twin-motor unit’ (TMU). Honda says its engineers have devised a “double-wishbone, double lower control arm front suspension that decouples the [front electric motors’] torque from the driver’s experience at the steering wheel”.
Although the company has now confirmed the displacement of the NSX’s petrol engine, it still hasn’t revealed the hybrid drivetrain’s performance numbers nor its output or fuel economy figures.
Honda may not be the first automaker to use a multi-material space frame, but this is the first time that this type of body construction has been used in a Honda or Acura model.
The company did consider an all-aluminium monocoque design, similar to the original NSX’s, as well as a carbonfibre space frame or unibody, but ultimately chose the multi-material path “because it offers the lowest weight and best rigidity, precision and hybrid powertrain packaging capability of any design”.
The company claims the new NSX is the first production vehicle to use ablation casting. Unlike traditionally cast items, ablation casting has rapid cooling phase, and is said to give items made this way the “ductility and energy absorption characteristics of extruded material”. Ablation cast items are used within the NSX’s crush zones and often operate as aluminium nodes.
Honda has attempted to replicate the original NSX’s thin A-pillars by using an “all-new three-dimensionally formed ultra high strength steel”.
Keeping the various components of a modern supercar cool is a major undertaking. Honda is proud that for the new NSX it has been able to do so without resorting to any active aerodynamic parts.
To ensure that various components receive enough cold air, the company employed a mixture of computer modelling, wind tunnels, 40 per cent scale models and real-world testing. There are 10 air-cooled heat exchangers responsible for keeping the various components of the car’s hybrid drivetrain from overheating.
The twin-turbo V6 has three radiators attached to it: two on the sides and one in the centre, which is titled forward at 25 degrees to improve its pressure gradient and reduce the car’s centre of gravity. The engine’s intercoolers are located in the NSX’s side air intakes.
The Acura NSX goes on sale later this year in North America. Right-hand-drive Honda variants will begin production in 2016, although the timing of the car’s Australian release has yet to be confirmed.