Hi All, a question on the differences (apart from diameter
) from the stock 850 lemans pistons v the 88mm Gillardoni pistons that are a common replacement for the 850 Lemans to 1000cc.
I am currently tearing down a Mk2 that has the 1000cc Gilardoni barrels & Pistons
I notice that on the Gilardoni 88mm pistons the crown/dome is ~6.5mm and much more pronounced than the standard SP1000/G5 crown/dome for the additional compression and chamber shape that the LeMans uses - make sense
However, the dome/crown is noticeably shallower then the original 850lemans pistons (~9-10mm? from memory).
My question - is the compression ratio maintained by a higher piston deck/top height (distance from gudgon pin to flat of the piston top)? And having never seen a set of OEM 1000 Lemans (mk4/5) pistons, are the Gilardoni’s the same as this or is it an improved design over the OEM 850 & 1000 lemans pistons