According to the FAQ the NA1 does signify it is C30A and the NA2 does signify C32B. I have a '01 NSX-T automatic and the Vin starts out as JH4NA1. Even according to Acura, 2002 automatics all have a Vin with NA1. I think this NA1 and NA2 is all inclusive of the chassis and engine and its only specific to the NSX.
For example, maybe in the future Honda might decide to build a car that has a variation of the 3.2L engine of the NSX, that engine code could very well be C32B. But the code that's listed in the Vin will be specific to that car, although it will mean, when decoded, that the car is so equipped with that engine. Just like Mitsubishi's potent 4G63 engine that's in the Lancer, old Galant VR4 and old Eclipse. They all share basically the same engine, but the vins will be different.
I guess what I'm trying to say is that I feel that the NA1 and NA2 gives you more information about the car itself. You know its an NSX. If someone told me their car was a 6G72, I would have to think long and hard exactly which car they are talking about. 6G72 is the engine code for the 3000GT, but there are 2 variations of the 3000GT, Z15A and Z16A. All have the same 6G72 engine. Z16A is the newer model.
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2001 NSX-T
- Bilstein Shocks
- '02 OEM Wheels
[This message has been edited by RyRy210 (edited 22 November 2002).]