So, are you buying new carbs from Holley? I take it that you have a 340, and can not get 340 6-pack carbs and are going substitute 440 carbs? I would still get Promax metering replacement plates and a Promax rear baseplate so that you can adjust the rear carb. Do you have an intake manifold?
I have a 340 and purchased a 350 center carb a few years back and should have purchased the end 500 carbs too.. and now I found out the only end carbs are for the 70/71 440 six- packs and yes I have a new six-pack manifold ..
