Personaly I do not think you need to zero deck the block.And 9-1
compression can be easy to get. Even just off the CCs of the head. But Zeroing the block can also help. Or like you said the
LP pistons can help. But bottom line is,You need to know what the CCs are of the piston , piston to deck & the CCs of the head.
Also you have to take into account is also the head gasket being
used. So as you can see The compression can be gained from
anyone of these area's. Lets say you stay with the Stock Block(decking)stock pistons,stock gasket thickness. You can just mill
to gain your wanted compession. Most 230,250,292 heads range from 72.76CCs -- 74CCs. So it just maybe a matter of knowing what head is already on the motor and Going with a different CC
head. Now as to a Lump ported head The air flow is improved right
from the start .100 lift. And it works with any Valve size even
the stock valve. But you can step up to a 1.84 or a 1.94 intake
an 1.6 on the exhaust.
my personal 2cents is go with the 1.8 & 1.6 for a good daily
driver if your still trying to get ALL that you can in the MPGs
or stay with the stock size valve. Even with a stock 1.72 vlave
and the Lump port & porting your still looking at least a 15% gain in the CFMs, Over a stock valved head & no porting.
God doesn't like ugly.
