Well you're right about WOT. The vacuum rise at WOT is very small especially with a four barrel. I didn't think of that.

Oh I think the throttle stop idea has potential. Its a different approach but not wrong. My thought for doing this type of testing on a dyno was similar. The dyno would need a load on it. My best low speed testing (idle circuit) was very gentle accelerations from dead stop holding the throttle steady.

I'm using the frequency channel because the rpm input died. This was after they fixed the Auxbox's built in MAP. They offered to repair but I needed to continue testing. Maybe I'll send it back now that I'm not using it for at least a few weeks.

Does the Urich version with FI still have the section on Road Race Tuning?