Your block is probably good for the same power or slightly above , 380-450 as the 200 block has a thicker wall allowing you to long-stud it(machining your headbolts deeper into cast.) when it will be capable of 500bhp (ten long studs)
The block is only a container! (blast shelter) the rest is capable internally, as it was over-engineered.
Its the bits that feed it that fall short.



Tim.