Ok Now I know that the S30Z 2-seater was the same for 240-280Z. The only difference was slight changes mainly for appearance, but same chassis and everything. The only reason they got longer was due to the bumpers. So anyway my main question is are the 260Z 2+2 and the 280Z 2+2 the same length?

Not sure how accurate this is: http://www.geocities.com/~z-car/specs/
But that site would have me believe that the 260Z 2+2 is about the same length as the 280Z 2-seater, I can only imagine because the 260 had smaller bumpers.

So are the 260 and 280Z 2+2 chassis the same? Just different bumpers?

 

they are all S30 chassis, other than emmisions and engine bore and fuel management and the bumper style, the rest is the same. same chassis code after all S30 so they must be