Anyone have a general idea of Compression ratio of these pistons (KB 240 KTM) with perma toqure Gaskets and stock 452 / 906 heads ?

Is it more that stock ?

Looking for 9.5 to 10.0

I'm just RIGHT NOW working on same build, and reading all what I have read and calculate, will need to install metallick gasket ( .020 ) and cut the 452 heads around .040 or 1 milimeter ( factory volume is around 90cc ) to be able to get close to 9.5 CR

KB240s even better than the stock ones ( around .090 more CH ), still are around .020 down in the hole, and the valve reliefs adds volume. On my engine maybe less down the hole due the block was sleeved in the past, so cut to decking.

just with closed heads or cutting HEAVILLY the open heads will raise CR around 10:1, but cutting hard will compromise some of the geometry, and require adjustable rockers and/or rocker shims

Even with 240's the compression still isn't that great. With stock heads and a 0.039 gasket I think it comes out to be 8.7 or so.