Replicating ph1 exhaust ports on ph2 head?

[Laine_16v]

I've got my 172 bare head, ive taken all teh valves out to do a bit of tidy up headwork (remove casting and CNC marks while removing as little material as possible), ive heard the ph1's have much improved exhaust ports over ph2 head.

Does anyone have any pictures of comparison or any adivce on how to work the exhaust ports on a ph2 head for some improvement? (obviously not asking for top secret headwork strategies from tuning companies )

thanks.

 

[sideways danny]

just have a look at a ph1 head if you can. the difference in gasket should give you a few clues too