Ok folks,  I took the Miller out for the first time, yesterday for a test and tune run.  Here's what we've got going...  BBF 460, .030 over-bore, CAM unknown (Been trying to find this out for over 4 months.  Compression is 11:1 with Keith Black flat top pistons, Weiand Stealth Intake Manifold, Edelbrock Performer Carburetor, Performer, 750 cfm, 4-Barrel, Square Bore, Manual Choke, Single Inlet (1407).

To start with, this carb has been a BEECH to adjust for idle.  Found vacuum leaks and pulled the manifold and installed new Fel Pro intake manifold gaskets and copper coated them down.  Also had installed a Rex Marine cable (throttle) Chrome Steel Plate for throttle mount that fits under the carb  (pt # 242-107), Found that it was warped and was causing a bad vacuum leak, pulled that and installed new base gasket and solved that leak.  All the vacuum leaks are gone.

So here's the problem...  Finally got it to idle at about 1100 rpm, any lower and the damn thing sputters and dies.  So we set it to idle at 1100 just to get out and see how everythign else worked.  Well, from 1100 to about 2200 rpm we are up and on plane, from 2200 to about 3000 rpm we are back to sputtering and running rough, stab the throttle and the secondaries open up and away we go.  The engine seemed to love it when those secondaries open up and dump the fuel.  Ran like a BAT OUT OF HELL WOT!!!

Do I need to go to a bigger carb or could I have just gotten a bad carb?

The fact that it ran like a bat out of hell at WOT suggests that the carb size will work. How is your ignition advance curve set up? Also may wanna try a carb rebuild as well.

The Ignition advance is set to 10* BTC for a total of about 34*.  The carb is brand new, if it needs to be rebuilt, Edelbrock can take care of that.     Came out of the box and onto the manifold.

Well, I can see right now, I'm going to have to remove the top of the carb.  DAMN!!!    

sorry, i thot we were talkin Holley

ok, I have a book on them somewhere, I think u need to go after the springs on the metering rods, make sure they move first. U dont have to pull the top but it may be a good idea to take a looksee

The Ignition advance is set to 10* BTC for a total of about 34*.  The carb is brand new, if it needs to be rebuilt, Edelbrock can take care of that.     Came out of the box and onto the manifold.

Have you checked total advance at 3000 rpm?  Most distributors only have about 20 degrees mechanical advance built in and with only 10 degrees initial you may not have enough timing.

Ok, here's the photos of the plugs.  I left them large so you can see their condition.  DAMN, I''ve got to figure out this thumbnail attachment thing.

sounds like a ford virus going around this year.

Just this year??? 

Funny how you chevy guys keep banging the fords my bbf ford just keeps running better and better I love waxing the big block chevy guys even though im a chevy man.....on subject the cam is unknown im assuming it has some size to it the edelbrocks metering circuts dont like cams with lots of overlap but check all your other stuff timing,fuel delivery system,vacuum leaks, if thats ok id look into sending back the carb trying a diffrent one they will hassel you on a return for sure,but if you covered all the other bases its the carb ive had really bad times withthe edelbrocks and mid to high performance engines and fuel issues,long live holley carbs......

I would keep looking for vacuum leaks,  if you can't idle down past 1100 rpms you need to fix that first.
If it has a vacuum leak you aren't going to tune anything.   Did you try the spraying trick to find leaks?

This is all brand new... Weiand Stealth Intake Manifold, Edelbrock Performer Carburetor, Performer, 750 cfm, 4-Barrel, Square Bore, Manual Choke, Single Inlet (1407). 

Hydraulic cam?

Yup!

Bet you know where I'm going.........

nope.   

Any idea how tight the valve lash is? assuming everything is adjustable, also does your oil pressure stay pretty steady?

Not sure of the valve lash and will pull a cover to take a look see.  Oil pressure at start is right around 80 lbs and pretty much stays there. 

It almost sounds like the valves are hanging open in the lower rpm range, which would act a lot like a huge vacuum leak, then once you open it up, the lifters get the neccisary "squish" and all is right with the world again, I have only seen this one time before on a 302 small block Ford, but sure sounds similar, It does not smell rich and starts super quik right?

Doesn't smell like there's too much gas, and it does start with a turn or so of the key and a few presses on the pedal.