honestly I doubt you could port a z22se head up to the level where it would get the full benefit from +1mm valves, but on a Saab head... I'm sure it can be done.
Like on your SC setup, your restriction now is most likely the exhaust ports and I bet you can free 15hp or more (and safer ones) with an extreme port and exhaust flange rework
Like on your SC setup, your restriction now is most likely the exhaust ports and I bet you can free 15hp or more (and safer ones) with an extreme port and exhaust flange rework