Welcome to the forum. Several guys including me have undergone the same problem. Go to the Tech Vault and check out the carb/intake section. Remove your AI "air injection" with the AI removal kit from
www.newspeedmaster.com they've got everything you'll need. Also this means you might be runnin a little lean on the main jet so check into
dinqua's carb tunning site. Its got a jetting calculator for whatever setup you've got.