What's the deal with the Poly 318

ok, flow test on a stock poly head, INT 25 " test pressure. 158 cfm @ .500 lift and climbing., EXH, 125 cfm @ 25 ", rework bowl and roof, 194 cfm and climbing, port velc @ 118 %. this is with stock valves, no valve grind. for you that want 28 " test, 165 cfm , int, 131 cfm exh, rework int port, 203 cfm. there was lots to be had if more work and sst valves were used. valve sizes were 1.84 & 1.56. I've cut down 360 valves to poly size and installed in 273 heads, picked up more flow and port velc. the head design is not bad.