One for the epoxy lovers

NHRA class rules for superstock dictate the as delivered from the factory accepted CCs for cylinder heads. They fill the bottom of the ports to be able to raise and re-shape them for better line of site and airflow potential. It's been proven many, many times that improving the line of site and short side radius, even though flow numbers may not improve, will make more power and lowering the port bottom in an effort to get to some magical cross section number almost always doesn't turn out as expected even if flow numbers go up. You can actually hear it on a flow bench as it's much smoother.