[gumby79]

Cd
Time is not so much a factor in throttle stop testing. Only top speed achieved and MAINTAINED with the Artificially reduced max power.

How long/ min test time. 2-3sec at peak to verify you are truly at max. Just has to be long enough to have multiple data points to average your speed value and confirm max is achieved.

How much is needed?
The higher you set the speed/ throttle stop(TS) for the, test the higher the resalution( smaller things will show better with more speed) .

Smoke in the tunnel is done at ~30-35 mph to prevent thinning the smoke too much to see the evadence. Fuel log records for others with OBD2 port access indacate that commutes under 45mph are less about Cd or A and more about RRC and the nut behind the wheel.

I might suggest setting your TS @
<35 for RRC testing
>45 mph for CdA

2nd peraon?
Using the camera on the 2nd gps phone should work a dandy.


Only issue I see with you using this segment of your commute is installing the TS block enroute. And possibly RRC temperature based discrepancies if this point in your community is not far enough to be at full operating temp for grease and oils.