Is the 3.4 and 3.6 based of the 3.2?

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here's how the M96 variants (non GT2, GT3 or Turbo) are pieced together (if i remember correctly):

the 2.5L and 2.7L engines share castings. the heads are identical and the bores are identical, but the stroke is slightly longer on the 2.7L (different crankshaft).

the 3.2L and 3.4L engines share castings and heads as well. i believe they also share cranks, but that their bores are different.

the 3.6L and 3.8L share castings and heads; the 3.8L has a larger bore.

The GT2, GT3 and Turbo engines are all more or less the same (and totally unrelated to the M96); the valvetrain on the NA is a bit different than the one on the turbo variants i think; the compression ratios are obviously different as well.