Thanks for the great info. I already have the Gear Vendors OD and was able to get 15mpg on the highway with a TQ carb and the Vintage Air running at 75mph. I currently have my stock 383 carb on and I get about 10-12 and it works really well when warm but I think the engine could use more. The startability is lousy. At this point, I'm looking for better starting and more power, so maybe I should look into a really nice carburator. So I guess I will do some more research