Gents...and hopefully a lady or two...I'm building a kick-@$$ roller 400, and will be topping it with a nice aluminum Edelbrock intake. I currently have, and was planning on using an Edelbrock 1406 electric choke carb for this motor. I understand that 400's love to breath deep, and that the 1406 is a nice tunable carb. Any input on if this carb choice will be sufficient for my 400's needs? Thanks guys...

 

If you're building a kick *** roller 400, why are you putting a little girly 600 cfm carb on it?

 

Mostly from using them in the past for various other projects. I currently run that carb on a Dodge 400, and it feeds it all day long with no problems. I have one in my garage, almost new, and it would fit the intake without a spacer plate. If anyone has a better suggestion, feel free. Please note I like electric chokes, and I want a carb with no gaskets below the fuel level. I prefer Edelbrock, but have used Holley,and like some of their carbs. Thanks.

 

Sure it'll feed it all day, so would a 350 cfm 2bbl, but you'd still be choking it. You'll get more power out of it at the top end with something bigger. If you like the Edelbrocks, try a 750 or 800.

 

Now I know this is not exactly accurate because it's data spanning two different engine manufacturers, but here's a little something that still to this day confuses me about carbs...their rated CFM, performance, and the effects on the engine. Again, just bare with me here...on't judge or assume I'm arguing.
The Dodge 400 I spoke of is in a 1973 Scout II. I originally had a Holley 750 on the 400. A friend had rebuilt it for me, and jetted it for the 400, as best he could anyway. It ran like crap. Idle was horrible, I always smelled unburnt fuel, and had to change fouled plugs waaay to often. It did not like high RPM's at all. At the behest of a buddy, I purchased an Edelbrock 1406, 600 CFM carb. NEW!!! Out of the box, with no extra tuning, I bolted it on, started it, and it ran like a new motor. I did not change anything but the carb. It had oodles of power off idle, and the engine didn't quit pulling until I let off the loud pedal at a respectively high RPM. I do agree that maybe it could be better, but I lost 50 CFM to the change and I benefited. The reason I still doubt is that I know a GM 400 is very different from a Dodge 400. They prefer different environments of fuel - air, and I am unfamiliar with what GM 400's like. I have a 1406, so no money out of pocket to use. I am currently looking through Ebay for a good electric 750, but I would have to spend $100 - $250+. I would love to hear from someone who has maybe used both a 600 and a 750 on a GM 400. Dang this ended up long...Thanks guys...

 

You can use the 600, it'll work just fine but it won't be optimal. There's really not that much difference between a Dodge 400 and a Chevy. It'd be hard to say what could have been wrong with your Holley without knowing more about what model it was and how the engine was built.

 

Well I'm going to continue looking for a suitable 750...I understand the advise from people more experienced than I am is invaluable, and that even though I don't quite see the same point of view, that there will be benefits. Maybe I should bolt on the 1406, break it in, and then swap, and compare. If one is better then the other, keep that one. With as many engines as I build, just for fun mind you, I'll have another spare carb for a rainy day. I still want to hear from people who have carbed 400's, and what they use, have used, or want to use on the torque monster. Thanks guys...

 

Try a search, there was a carb comparison awhile back where the tech guys from BG chimed in about carb flow numbers and how different mfg's used different numbers. (it was before the big crash of '05) so it might not be around....
TRY:http://www.barrygrant.com/pages/techsupport.aspx

 

as far as tuning goes, yes the 1406 is very easy.