Sorry, lots of updates at once but time is my enemy.
Having the inlet manifold apart I have been toying with the idea of match porting the runners to the fuel rail / butterfly plate. The inner section which houses the fuel injectors matches quite well to the gasket diameter, the manifold runners on the other hand are 2-3mm under size almost around the entire circumference. Now common sense says that opening these will be better for flow with less restriction / obstruction etc, etc. However, is this really a worthwhile exercise for a mild engine? Has anyone on here actually had any measurable results doing this or used a flow bench to compare factory with a match ported manifold? Realistically there will be many other factors limiting power before this in my build, but I feel that it should be a "whilst I'm there" job.

I am not touching the head yet, so is it worth spending several hours doing this or just leave it? Any feedback / opinions? Would love to hear of other experiences.

Also for now I am leaving the butterflies in.

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