Best Carter carburetor upgrade for 67 383 s?

[LovetheA's]

Asking for some help;

I have the stock Carter afb 4298s on my 67 383 4 speed formula s and want to upgrade to a bigger cfm Carter that I can just rebuild put on and go. I know that my 67 intake is limited by smaller openings primary 1 7/16" and secondary 1 9/16". Could I for example put on the Carter carb that came on a 67 440 4 speed B car and improve performance as I feel that my engine is undercarbed? Is it a moot point because of the limitation with the smaller intake openings and runners. Can I put on a spacer of some sort to remedy this without changing intake?

Carl

 

[rumblefish360]

You could put a spacer under the new carb. I would not do that myself. I would ether do;

Bore the intake holes out for the larger butterflies of the larger carb

OR

Get a TQ intake and large TQ carb.

IF staying with an OE look, becareful of what carb you pluck from another engine. The early 440 engines did indeed come equipped with a small AFB.

Make sure you get the "750cfm" AFB or AVS, which would be my choice, AVS that is.

 

[LovetheA's]

You could put a spacer under the new carb. I would not do that myself. I would ether do;

Bore the intake holes out for the larger butterflies of the larger carb

OR

Get a TQ intake and large TQ carb.

IF staying with an OE look, becareful of what carb you pluck from another engine. The early 440 engines did indeed come equipped with a small AFB.

Make sure you get the "750cfm" AFB or AVS, which would be my choice, AVS that is.

Rumblefish360

Thanks for the advice.

Carl

 

[Marcohotrod]

what do the primary openings in the intake measure? if smaller than 1 9/16" grind them larger or throw on an aluminum intake-dual plane. run a Carter from a 440 magnum 375 hp like I do=750 cfm, 1968-1970 ish, I picked 1 up from a swap for $100.

 

[LovetheA's]

what do the primary openings in the intake measure? if smaller than 1 9/16" grind them larger or throw on an aluminum intake-dual plane. run a Carter from a 440 magnum 375 hp like I do=750 cfm, 1968-1970 ish, I picked 1 up from a swap for $100.

Primaries on intake 1 7/16" and secondaries 1 9/16".

 

[1969383S]

I am using a 800AVS edlebrock on a TM-6 with factory air cleaner 69. If you are running a stock air filter config on a 67 with factory intake I would think an adapter would still fit under the hood.