Truckmount Wand CFM Testing Comparison

Just finished our 1st Series of TM tests with a new Calibrated CFM meter.
Airflow results with 14" wands on the presprayed carpet .
Each wand had 100ft. of 2" hose all the way to the TM (35HP w/#47 Blower @ 16").
14" Bentley single wand - 258 CFM
14" DangPro Ti single wand -230 CFM

Next we tested Dual Wands - a 14" + 12" on the carpet:
14" Bentley + 12" on 2nd hose = 195 CFM
So adding a 12" wand decreased the CFM to 75% of single wand.

Next we tried reducing the 35 HP TM lift to 13" hg (same as most National Brand TM's). . . .
We tested Dual Wands 14" + 12" on the carpet:
14" Bentley +12" on 2nd hose = 162 CFM
So Combo of 2 wands @ 13" decreased the CFM by 18% compared to 16" hg Vacuum Level .
This demonstrates the necessity of High Vac Lift levels on TM's.