[xlr8or]

Clois and Bran3b,
The metering spring change on Edelbrock carbs are really only useful for flat spots in transition from cruise mode to power mode. If your problem occurs during transition from mid throttle to heavy pedal the springs probably won't do enough. When your already up at 3000 rpm + and good bit of throttle it is most likely going to need a pump adjustment and jet/rod change since your are already beyond the cruise/power mode switch.

Remember keep going rich until it doesn't get any better when jetting and then back off one step. Better a little rich than lean.