Advice on stroker build with cracked cylinder
??? What were you wanting/expecting? Are you planning on running race fuel?
Perhaps there is a communications issue on what it is and means. Low to mid 8's DCR is doably safe for pump fuel, WITH AL heads, but is not 'low' for DCR, in fact is it on the high end for DCR, for pump fuel use. Stock stuff was typically in the mid to upper 6's.
That level of DCR is not good for the lazy hot-rodder; you have to pay close attention to detailed tuning. If you go too high on DCR, or mistune a high DCR engine, then the engine's combustion will reach detonation conditions, and quickly self-destruct. It will melt/crack/break pistons tops and shatter piston rings.
Again, forgive me if I am blathering on too much LOL