Why are the older Z34's faster than the newer ones?

MCDX

2010:
In Europe the tuned down the engine from 243 to 241 kW to meet emission standards.

2012:
added Oil cooler

2013 FL:
added sound deadening


Allthough I think all the fancy pieces of paper from Nissan always stated 5.3s from 0-100km/h (62mph) for the manual and 5.6 for the Auto. 5.2 for the Nismo.
0-60 normally seems to be roughly 0.2 less.

But, several tests seem to have high 4s for the car in general and normally a faster time for the non-Nismo as the suspension is a bit softer, weight shifts easier to the accelerating wheels and therefore generates more traction.

Nevertheless I can guarantee the normal 370Z Sport with the AT is the fastest Z on public roads.
Otherwise driver-mod or bigger b* required.


EDIT: to sum up: I'd never buy an older car just because it could be a friction of a second quicker.