[freebilly]

They were actually faster off the mark than the 280z (none of them were particularly blazing going from 0-60) & had a faster top end speed than either the stock 240 or 280.

[AlBondigas]

My memory = completely opposite from yours, i.e.
Z went from 2.4L to 2.6L in'74? to compensate for emissions hdwre.
('74 also was 1st usage of cats by most of the imports)

You might be citing mag reviews of (Fed) cars, but the '74 260 (cal) was a total stone
The hot setup was to get a 2.0L (Jpn) I-6 from K Watanabe