I cheat- - - - -my "flow bench" is the "blow" side of a shop vac, with a water manometer connected to the pressure hose. Lock the valve open at max cam lift with a shaft collar and no spring, and pressurize the port, then adjust a bypass valve in the pressure hose to get a few inches of water indicated on the manometer tube. Once the first port sets the standard, check and compare all the others to the baseline it sets. I think my total cost was less than $100.00. With the right setup, both intake and exhaust ports can be measured.
www.ebay.com/itm/314715194529?Jerry
