time to rebuild
same with exhaust manifold and the heads
have the heads pollished out a bit...
new camshaft.
flat top pistons..
I mean the list is very lengthy, but really using what you got, the best thing to do is have the block prepped properly. If you really do need to bore over, you need new pistons anyway though.
but using what you have, intake and exhaust port matching and then some headwork to open up airflow is probably the cheapest thing you can do (if you do it yourself)
BUT it allows for a lot of room to screw up if you do attempt to polish everything

port matching isn't too horrible though.. use a rotary air tool with a tungsten carbide tipped cutter.
draw an outline of what you want to remove, using the new exhaust/intake gaskets to trace an outline.
it helps a little bit once it's running again.. How much? probably not a whole lot.


