Originally Posted by ira-k
You got it...Should I clamp my tubing right after the gauge and get a max pressure reading or just let it free-flow?
Looking forward to seeing the V-8 and Bonnie spec's...Well if the full version of Open Office works I'll be able to see it..
Free flowing is what I'd need to check the radiator (I was going to use my estimator to guess on a flow rate), but if you clamp it shut, that would tell you what your two pumps in series maximum head pressure is. The curves Alex sent me over for the DDC2 with top is about 8.2 psi per pump, so two in series should theoretically be about 16.4 psi.
The best thing for pressure drop would be to run both pumps with your pressure guage before the radiator free flowing and measure a pressure reading, then move the guage after and measure a pressure reading also free flowing...then do a quick flow rate check.
Attached is what my estimator gives me for two DDC2 with tops, 4' of 1/2" tubing, and a GTS240. You should see a little over 3 GPM and about a 5 PSI pressure drop at that flow rate.
.jpg attached below