What are these pistons?

[JJK1204@domain.elided]

What compression ratio are these pistons asked the second mouse?
Continuing the mice in the 1750 engine saga, upon looking at the bottom of the
pistons I have found they are Venolia #306. If it helps they are the flat top
style and the flat is around 1 5/8" wide at the center of the piston.

John Katos

p.s. It is pretty well unanimous that the cams are 7L for a 1600, 245 duration
and 9.5mm lift.

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