Speedmaster head hypothetical

Earlie A said

My opinion and experience (for what it's worth) is that throat size is a result, not a goal in and of itself. The size of the throat is a result of getting the bottom cut angles and blending to direct the air where you want it to go. I have also found that the throat size can be used to regulate flow separation to some extent. Bottom cut angles and blends will be manipulated based on the port in front of the throat and the chamber after the throat. To say a throat needs to be X% is just incorrect in my way of thinking.

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I’m not suggesting you make the bowls a given number, but steeper than 45 degree seats usually want the bowls over 90%.

I’m not sure how you do your seats/valve job but I start with a cutter that sets the bowl at 91ish%.

I’ll hold my comments a bit longer but your flow numbers gave away that your bowl % was smaller than I’ve ever used with other than 45 degree seats.

Again, we are getting into the nebulous realm of is the flow bench telling you the truth or not.

Also, have you flowed both ports in reverse? What about at lower or higher than 28 WC?