I know Paul Yaw has a flow bench, but i'm just curious if there aren't any more people checking their side housings and rotor housings before and after porting. Myself i have used one since 1998 and have gained a lot of airflow specially when i started using them for measuring peripheral rotor housings. I built one 13B with PP and a Weber 51mm carb distriburless ignition and my theoretical intake flow was 290hp,when i put it on the dyno it made 297hp@9000rpm with 185ft/lb of torque@8500rpm with 54mm 23#long primaries. The engine idles nicely at 1200rpm and pulled easily to 9500rpm with no bog or hesitation. At last the intake hole was 44mm in diameter at the smallest point in the housing (smaller than factory ones).