I just bought a 72 Lemans with a 400cui and I'm wondering what will be the best carb to use on this engine? Any input from you guys out here?

What are you trying to accomplish? Performance or economy, or a reasonably street-worthy balance that won't break the budget? Do you plan to keep the existing 4 bbl manifold? If it's a 2 bbl don't bother changing carbs, you won't see any improvement in any category. As far as the stock Rochester 4bbl... it's probably a better carb than most aftermarket ones for general everyday street use and reliability (If it's working correctly). To see any sort of gains in performance you will need a new manifold. If your carb is shot, the Edelbrock 1407 (750 cfm) is as large as you should go on the low-compression '72 engine. Another option you might consider is a Snow methane injection system, which is about the same cost as a carb, and will get you more HP, better mileage, let you run on cheaper gas, and is a 3 hour install with ordinary hand tools. Good luck!

gotta agree with norm ^ , holleys are getting very expensive these days , i bought a 750 w/vacuum secondaries about 7 yrs ago for 350.00 brand new , now they want about 450-500.00 bucks for the same one ,but you do get a nice trottle responce, on the other hand the stock rochesters are awesome for the street and a lot of companies are rebuilding them like summit,but if you order from summit call their tech line @ 330 630-0240 and they can hook you up with exactly what is best for your engine, even if you don't buy it from them they will still help you out, their regular sales people know shit about cars. good luck

Thanks Fella's