I dont know how to put it in words or if you guys would understand what im gonna ask..but lemme give it a try.

About the combustion chamber ( heart shape ) - If we place a gasket on the top of it, follow the shape of the piston, and then machine it ( change it from heart shape to round, following piston diameter ) with a depth of about 2-3mm...will this make any positive difference to the compression ?

Quote:Less compression is good for some uses
More compression is good for other uses

Which do you want?


And do you mean taking a B type and machining into a C type?

YES. Exactly.

Basically it lowers the compression right?
And, if the block is fitted with a taller piston, the volume ( CC ) and compression ratio should increase right?. Correct me if im wrong...

Don't know if it will work with a GX head though.
My second spare GX head was machined to the max by the previous owner due to warpage.I thought about grinding the one chamber a little to get the cc's equal as everyone was 10,5 : 1 except the last one that was 11 : 1. I could see it had some detonation marks on the valve heads.
I talked to a cylinder heads specialist and he said there is not enough meat to do it.

Assuming the head hasn't been milled down to begin with, yes I think you can do it.

You end up with a popup type piston, which expands up into the combustion chamber. As I understand, these are less efficient than a heart-shaped chamber and flat-top piston.