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Olly398
@Dammit
Current bore (lol) is 96mm, we are going to 100mm. With the 3.4 litre 78mm stroke crank this nets 3.7 litres. However, Baz just suggested we use the 2.5 litre, 72mm stroke Boxster crank. This would mean capacity would actually be unchanged at 3.4 litres, but 72x100 rather than 78x96.
Why would we do this?
For a nominal Mean Piston Speed of 20.8 m/s, a 78 stroke would net you 7846 rpm, whereas the same MPS with the short stroke gives 8666 rpm.