I'm working on an excel spreadsheet (yes, I was bored when I started it) that will calculate the compression ratio for all the various configurations of the m20.
I've got the displacement bit working fine but need some more info to calculate the CR. I need to find out the combustion chamber volume, piston dome volume and piston deck height (distance between the gudgeon pin and piston top, hope I've got the correct terminology here) for the b20, b25 (pre & post facelift) and b27(eta) lumps.
Has anyone got this info available?
If I can get it working I'll try to find a way of hosting it somewhere and post up a link to it.
m20 Combustion Chamber/Piston Dome Volume
Moderator: martauto
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eta
- E30 Zone Regular
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I already have such a spreadsheet. Send me your e-mail and I will fire it of to you. This spreadsheet takes account of headgasket volume (crushed) and has euro and us versions of the m20.
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clarko74
- Old Skooler
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Nice one. You have pm.
clarko74
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Turbo-Brown
- Boost Junkie
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The deck height of the piston is referred to as the compression height.
On the M20 pistons which have a raised dome, it's measured from the CL of the gudgeon pin to the shoulder of the piston, and then the raised features are all above that shoulder....if that makes sense.
It's 34.2mm for the B25 I think
On the M20 pistons which have a raised dome, it's measured from the CL of the gudgeon pin to the shoulder of the piston, and then the raised features are all above that shoulder....if that makes sense.
It's 34.2mm for the B25 I think
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clarko74
- Old Skooler
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- Location: Kent
Cheers Turbo-Brown, much of the info I've got so far has come from your Twin Seq. exhaust manifold thread.
clarko74