We did a test which suggested getting the PV's open slightly earlier could be advantageous; we did as power run, killed the ignition at full revs, then unplugged the PV unit and did another run (so the PV's were as open as they get).

Obviously the curve with the PV's fully open was worse at the bottom but it crossed the normal curve and made more power for a few hundred revs just before peak power.
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