Hello greenteagod,

As always I have to agree with Phil S., the first thing that every one does wrong when they are about to "attack" a head, is that they do "too much" (a bit like sex for the first time???).
Ending up with a result that wasn't what you expected.
Keep it simple, and you'll probably find that it works better than you expected.
All though mjamgb has quite some good qlues too more extensive work, I must make a statement about the flowbench: THROW THEM IN THE BIN!!! (or use them to grow plants in, thats what the serious engine builders do).
The only indication tha a flowbench gives is that a bigger port flows more than a small one, hence a Keith Black pro-mod head should work better on a B18 than the OEM head (might be true if you rev it to 19 000rpm's).
Also a flowbench takes no notice that there is a few moving parts in a head (such as valves...), they tend to disrupt the flow and create back-pulses from time to time...

Best regards, D.E.Sweden