Speedmaster Small block porting tips and results Part 1

Anytime you unshroud the intake valve at the chamber, you open the flood gates to the common wall. Either do it first and work with it, or do it in very small increments to get where you're going. The turn isnt worked yet , we know that much, but it's ootb better than a factory production head and imo shouldn't take much laying back.

This port PBR is working on has gone into what's called 'saturation' for .100 lift then drops a few cfm... That's telling you the ssr needs work.
What's the cross section at the throat in front of the valve guide, is it bigger than 1.625?
You get that 10-15 cfm by unshrouding, but you know its work after that. And depending on the head.. well ,that's why it costs. The jump from 400-600 to 1000 starts there.