with just these changes and no others and the same head gasket. the new cr will be .25:1 higher than before.
The ZZ4 L-98 heads (113) work really good with full porting and larger LT-4 2.00x 1.56" valves.
In stock form the ports are modest. But they shape is basicly not bad and there is enough meat to carve
a nice finished hi flow intake and exhaust port on these heads.
250+ cfm intake and 200+ cfm exhaust when done. The chamber gets some work too.
Look at the vortec head and Lingenfelters CNC ported OEM L-98 head CNC'ed combustion chamber for inspiration.
I believe they still sell these 450+hp capable ported L98/ZZ4 heads.
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If you get the opportunity to see one of these CNC ported L-98 heads you will see what needs to be done to wake up
the L-98 113 head. They work good when done right.
You will know how much power improvement you got when you run it down the drag strip a few times.
MPH from time slips and true car weight with driver. It never lies.