It should go lean instantaneously. That's what we're telling you.
It's different than when working from the idle circuit and going WOT.
If you use the the throttle to crowd a vacuum, the leaner AFR will stay fairly constant.
Here's a log that shows proper response opening the throttle from cruise but hits a dead spot. This past winter I took this carb off the shelf and fixed the calibration issue. Some point soon I'll put on the car and find out if I've solved it.
First markers shows slight acceleration with increase in throttle from cruising to light acceleration. Vacuum drops from 19"Hg to 16" Hg.
Second to third marker shows more acceleration by opening the throttle to maintain 14" Hg.
Gently adding more throttle to drop the vacuum as low as 11.5 " should have resulted in more acceleration. That's the 'dead' spot.
If this was a higher speed test, the AFRs would have been leaner.
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