Hello Bob!
Ok, thanks a lot for this flow chart, because we will order exactly these Si valves in 1.88" and 1.60" in the next time and after porting the in- and outlet, we will also use a flow bench for the results of our work, if it is possible, i will show you here on this thread!
Right, we will use a 2,4L head, our "God of porting tuner" here in Germany uses also an flow bench and he selled him on ebay:
Sportzylinderkopf f. 2,4 Ltr. Opel CIH /Kadett C/ bei eBay.de: Antrieb, Motor Getriebe (endet 11.11.07 21:00:00 MEZ)
He promised 221 HP with a intake port flow from 198 cfm,
but he uses 45mm intake valves, we will use 47,75mm, i think
(hope) maybe we will come to 230 cfm, we will see!
And thanks for congratulations to my birthday...
Best regards