Good information for the most part. The serdi is good but the sunnen VGS-20 is pretty much the standard in the racing industry. I wouldn't advise home porting on a head that you will actually run on your street car. You can easily do huge amounts of harm (not only power wise but reliability too) Headwork is the most expensive part of building an engine. The cylinder head is also most responsible for power gains (or losses) and RPM capability. Whether it's actually worth it, dunno but supply and demand.
As far as what valve jobs to run and whether the valve job is 'radiused,' combustion chamber polishing. All of that: where to remove material, where not to,swirl and tumble, runner surface finish. The smartest people in the world argue about that crap.
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[body]Generally, good headwork leaves the floors of the port alone since most of the flow activity in a port is near the roof of the port. The roof is the outside radius of the bend going to and from the combustion chamber and by inertia, most of the air wants to flow up there.[/body]
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This isn't exactly true. Theoretically, yes this supposed to happen in a specific application, but even in that one example in an actual running state and varying rpms with a valve opening and slamming down 3000 times/minute who knows what the air does? How a port is designed results from induction type and efficiency, application, rpm range, camshaft specs, etc. Someday, someone will develop a flow device rigged to a spintron. That will be much closer but still not 100%. What i've said probably sounds like mindless rambling. alls i'm saying is that 90% of what you hear about how an engine should be is wrong. Anybody (short of a few) that writes books wouldn't be writing books if they really knew what they were talking about and the people that really know wouldn't sell their information. I'll try to compile a list for you guys when searching for a machine shop to do headwork and whatever else.
