For you guys that have either dyno data or use the on-board wideband O2 meters, do you find that your "tuned" WOT air/fuel ratios from bottom to top of RPM curve are fairly close, or do they tend to swing one way or the other?

I spoke w/ Dwayne Porter about seeing this on the dyno data for my engine where we tested a few different carbs. In this case, my Claw had a lean bias (not a "spike, a more gradual change) in the mid-range of a 3500-7000 RPM pull (i.e. ran richer near the bottom and peak RPMs). His "dyno mule" Holley 850 annular carb showed much more consistent a/f ratios across the pull, as did an 8896 HP 4500 we tested.

We know this can be the result of a combination of things... emulsion settings, booster signal, air bleeds. However, pinpointing the reason for going lean in that manner isn't so cut-n-dry. It just "is" at this point.

EDIT: I'll throw another related question on here... do you "want" to see a different air/fuel ratio at peak torque than at peak HP?

So... what have you guys seen from your own tests?