Boost climbing to 28 psi by the top of first gear. Dipping to 27 psi boost for the shift into 2nd. Then slowly ramping to 31 psi boost by the end of the 1/4 mile run.
Doesn't seem like overly wild boost numbers to me. A very conservative boost rise curve. I don't think it's the boost.
On the flow bench, the heads flowed 210 cfm. The intake valve size is 1.835". The exhaust valve size is 1.50".
Don't think it's the heads at all.