Transition circuit is a step or two fat... As Glen said, most are fat out of the box... If you don't have the Edelbrock calibration kit, you'll need to get it then follow the chart in the book (or on the Edelbrock site) to get the carb dialed in... Once you get the calibration right on the carb, you may want to reconnect the vacuum to the ported side of the carb, then work on the vacuum canister to slow down the advance rate a bit.....