flow figs

The short turn would change on every head depending on what engine the head is going to be used on. If the cam is only going to be in the .480-.520 lift range then I would leave the short turn as tall as I could and not radius it any. As this makes the air flow peak really quick and this is what you would need if the cam is small. I generally like to have the head airflow peak about .080-.100 before peak lift of the cam and hold the peak flow to peak lift of the cam, this way your getting maximum air flow and velocity or cylinder filling pretty much all the time through the range of the cam.