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I did some back of the envelope chicken scratches while having coffee. The B18B head gives a nominal compression ratio of 10:1. Your 0.040 overbore increase the engines swept volume - easy to calculate. The 0.010 shave decreases clearance volume - not so easy to calculate because of the irregular shape of the combustion chamber; but, I took a guess at a form factor of about 50% of the full bore. I ignored the effect of head gasket variability and assumed that the pistons are flush with the head (which is what Volvo assumes when it provides the compression ratio specs).
If the B18B head has not been messed with, I guesstimate that you will end up with a compression ratio some where around 10.3:1 - 10.4:1. If the block is decked for flush pistons you should live happily with 92 octane fuel, the proposed gasket and no detonation. If the block is not decked, you may have to reduce the ignition advance just a nudge to avoid detonation; but, that is a may not a definite.
The k cam has slightly less overlap than the D cam I use which will result in a slightly higher static compression which may change the tendency to detonate. Only testing will confirm.
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