The HSC never even made it past the concept stage. The concept car was simply a NA2 NSX chassis with different body panels and a different interior. The model was only minimally functional and really just intended to give the public a visual glimpse of the design direction for the next NSX, not a production-ready design concept. The project was never pursued due to a lukewarm response from the public and belief inside Honda that the concept was not enough of an improvement over the existing NSX to be worthwhile.
The original Dual-Note concept used a V6 producing 300 hp (much like the NSX at the time) and two wheel motors producing 50 hp each for a total of 400 hp (300 + 50 + 50). It is a brilliant concept worthy of the Honda of old, but in 2001 it was not workable from a production standpoint.
Fast forward 10 years and now the technology seems to be maturing to the point where this is possible. The Dual-Note powertrain developed into the SH-AWD system currently in use across the Acura product line. I have this system in my RDX and can attest to its amazing performance. All Honda did was replace the electric wheel motors with a centrally-mounted electric differential that distributes engine torque via a driveshaft to each wheel. While the wheel motor is a novel concept, I suspect Honda will instead use the proven tech of the centrally-mounted electric SH-AWD differential, but instead of hooking it to a driveshaft, it will run off of a co-located motor. This will also have the added benefit of keeping the heavy motor on the centerline of the car instead of at the wheel hubs. Where the driveshaft normally would go under the middle of the car, you will see the lithium-ion battery pack. This again keeps weight low and in the middle of the car.
This layout offers some incredible performance and economy potential. Just think of your NSX having two modes: "Sport" and "Eco".
In "Eco" mode, the the car adjusts power to only that necessary to maintain current speed, with the front electric motor wheels providing 75% or more of the driving power- much like the current SH-AWD system. At the same time, the iVTEC V6-IMA part of the package will use VCM code to shut down to run on 2 or 3 cylinders- just enough to keep the battery pack charged and providing 10-25% drive to the rear wheels. Finally, the engine would reduce power and emissions further by switching to either a third "econ" VTEC lobe or a fully variable cam. On a 3000 lb, all aluminum car, I bet you could see hwy mpg of at least 50 using this configuration. Thus you could cruise the interstate in your 400 hp exotic NSX with the same fuel economy as a Prius.
In "Sport" mode, VCM and the "econ" VTEC shut off, giving you the full power of the V6 and VTEC at the rear wheels. Also, the SH-AWD logic reverts the power balance between the wheels to maximize acceleration while utilizing the full 100 hp of the front motor. Butterflly valves open up in the mufflers to give you the full effect of the 9000 rpm V6. Your NSX is now a 400 hp AWD firebreathing beast.
Pretty cool, huh? I say go for it Honda. This is the best idea you've had since the original NSX. If the styling is right, this could be a game changer for the industry.
