It seems nailing down dynamic head loss is the most critical aspect of properly selecting optimum equpiment to run our pools. It also seems to be the most fleeting.
Mark definitely has it understood, and I hoping the end result of the information he is working on is a quick and easy accurate way to tell us what we need to know If it is, what follows may be moot, but I'll throw it out anyway.
I propose we band together and buy a head loss determining "kit" that we could each share. A vacuum gauge, flow meter and necessary fittings and adapters to make it work on most set ups, which can possibly be determined by those wishing to participate posting specific info on their pool and those educated in what it would take to do so figuring out what is needed. If enough people are interested it should bring down the individual cost to a reasonable level. My gut says $150 should more than do it, and if 10 people are interested, that's only $15 each.
Once the kit is figured and a total cost determined, everyone wishing to participate would throw and equal portion of $ to the person chosen to purchase and distribute the kit. I formally nominate Dave, since TF test kits is already up and ready to go... do I hear a second?
Anyway, once Dave (or whomever) has the money, he orders the stuff and puts the kit together. We "draw straws" to determine the order in which we get access to the kit. 1st up "orders" the kit from Dave, paying only S&H, but secures the entire cost of the kit with a CC. That way if it's not returned, their card is charged and a new kit can be purchased. Once #1 is done (they have a certain time frame to do so) they return it to Dave, who contacts #2, rinse, repeat
I have no idea if this can even be done, but it's been on my mind so I wanted to put it out and see if anyone would be interested. I for one would LOVE to know my DHL once and for all. As I understand it, once you have it nailed down, it's a matter of simple calculations to figure how it will change based on the pump selected.