A quick carb question

[IowaCharger69]

I have a bone stock 400 out of a 1974 Dodge Charger, non HP, in my 69 Charger. On that 400 I have the stock 400 heads, but the intake from my 1969 383 Magnum.Ii am having some carb issues. I have a Holley dual inlet 750 on there now. I am beginning to think that it is waaaaay too much carb. I can't seem to lean it out far enough to make it not burn super rich. I do have an electric fuel pump but I have it regualted to 4 lbs. That seemed right. So my question is: Is the 750 too much cfm, if so what would you suggest. Please keep in mind that the intake I have is meant for a Holley like bore, and I am trying to not change it.

Thanks in advance!

-Tom

[resq302]

I want to say that my 383 has a factory carb that was something like 625 cfm?

[SeattleCharger]

 

[Plumcrazy]

Put an Edelbrock #1806 on it. 

[Nacho-RT74]

stock TQ carb on 400 are TQ 850 cfms

[Chryco Psycho]

the 750 is fine , you have other tuning issues , when you say rich when is it rich , at idle , cruising, WOT ??
are the spark plugs black ?
First check the float levels , you can also set the fuel pump to 6 PSI before resetiing the levels
what may be the problem is at idle the cam may be too big to make much vacuum this can cause 2 problems 1 the power valve may not be staying closed so you are dumping fuel , take a vacuum reading from the manifold at idle , if it is in the 7" range or less you need a lower rated power valve to stay closed also a long duration cam will cause reversion & cylinders will misfire making the engine seem rich at idle even while they are set lean at all other Rpm ranges
I f the plugs are black you either have the mixture screws set too ruich or the powervalve is open , if it is blackening the plugs while cruising you need to insatll smaller jets