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That set got nothing but new valve seals and a couple of springs shimmed up.
The big wide seats aren’t the best for performance, but as long the the runout is decent, it’s not going to cause any problems.
Guide clearance was a tick over .002”.
Again, not fantastic for new aluminum heads with bronze guides, but it won’t cause problems.
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With a proper valve job and a basic bowl blend I’d expect to see a gain of somewhere in the 10-15cfm range from about .400 lift on up.