Finally got the videos sorted and some of them uploaded.
https://www.youtube.com/watch?v=oZ8XQAew-Ok
I pulled over 1/2 a block from an on ramp, shut the engine off with the elec vac pump running then started the camera to show the sound of the pump running (gauge at 15" HG {0 to 8" HG is green, 8 to 15 is yellow, 15 to 28 is red}). Started the engine and merged onto on ramp traffic with impatient drivers behind beeping. The gauge in front of the vac gauge is a boost gauge.
As you can see, during cruise it is at around 10 to 12 " of HG, hard acceleration drops it down to 8" of HG. Shifts were smooth with no clunks or flaring. Braking was normal and does not show on the gauge (unless I pump it many times in succession).
I have since routed the cable from the pump inside with a cig. lighter plug so I can manually turn off/on the pump. During a steady cruise, if I turn off the pump, the reservoir vacuum drops from 15 to 10 " HG in around 15 seconds. At 10" of HG, shifts are still normal. When it goes below 6" HG is when the shifts get rougher. If I set the vacuum switch to 11" HG to turn the pump on, it may limit the duty cycle of the pump to be a practical system IMO.
I did this elec vac pump test because mach4 says it is not viable for automatic transmissions just to see for myself if true.
My results says otherwise. I dunno what's different in his setup. Different vac pump? Different reservoir? Differences in VCV and transmission modulator? Different leakage rate in the system?