Wally, Doug's posts are excellent. I can only emphasize his comment about a small change making a marked effect.
Carter used to tweak in metering rod increments of 0.00125 inch.
Another tuning tip is to vary the float adjustment. Adjusting the fuel level plus or minus 1/32 of an inch will make a difference (float adjustment is ALWAYS critical). Don't do more than 1/16 inch higher or 1/8 inch lower than specification.
Jon.
