I know they are relatively new. But a lot of people change their carbs. Anyway, to answer your question yes, I can rebuild a quadrajet I have rebuilt more carbs than a lot of people have ever seen and have recently rebuilt the 650CFM q-jet that is currently on my ride. However, it's a little difficult to run the divorced choke carb I have with a Performer manifold. No sense buying another q-jet just to replace the one I already have, that I am dis-satisfied with.