Interesting snur. I was informed that it was a 15 % loss in pressure for every 90 bend. Even someone brought in a demo. It wasn't for pex but some new toilet design on making the flu s h more efficient, but I took it hy the same principle (the demo changed the water flow pattern if I recall) ill have to look back into the reduction loss at 90 bend. If what you are saying is true
Yep that's the difference between pressurized flow and non pressurized flow. The bends certainly have a large effect on flow with non pressurized systems. That's why drainage pipes have "sweeped" or gradual bends, instead of hard bends like pressurized systems have.