Hello Rob,

Your head pics look good so far
I left my exhaust port exit size much smaller to keep up exhaust velocity.
We tested a port making it larger (almost the same size as ERST turbo manifold)
and did not see any flow increase. This means a definite velocity decrease.

Removing the intake valve guide in the inlet port is also a good thing. We saw a 10 to 12 cfm gain by removing the protruding guide. The air velocity near that valve guide is
extremely high. A 10 cfm increase in flow (if velocities are still in a good range) will yield
20 HP at 15 psi boost.

One note of caution - the inlet manifold.
The inlet manifold is a source of major airflow restriction as well.
Porting the cylinder head by itself, and not looking at the intake manifold
is a huge mistake.
We have ported a cvh head with standard 42mm valve to reach 193 cfm @28" and 0.450" valve lift. This was with a 36mm diameter inlet port (near factory size).
However, when we added the intake manifold nearly all of our 40+ cfm gain was gone.
After reshaping the inlet manifold we are at 175 cfm - still alot to gain.
I can certainly see a large gain made from a propper tested intake manifold.

Again, we would not have discovered how bad a factory intake was without the aid of a flowbench. Anyone who says flowbenches are useless - is fos.

Increasing the efficiency of the entire inlet path is free HP. Increased power at lower boost levels.

Cheers,

Perry