center carb difference?

[Bill Monk]

I figure this would be the right section to post this on so here goes. Can anybody tell what the difference is between the 19-70 4144 center carb and the 71 4670? Jegs lists both but they are over $800 bucks, summit has it for $553 but doesn't list the 19-70, only the 71.
My car is a 69 but not an A-12 car so being perfestly original doesn't matter to me.

 

[PurpleBeeper]

I "think" the only difference is carb jetting. The '71's "might" all have the "California clean air" vents on the center fuel bowl instead of just the rubber plug/vent, but I'm not positive.

 

[RJRENTON]

I believe the major deference is the idle mixture circuit. It has a fixed idle fuel feed restriction (non adjustable) and an adjustable idle air bleed. This operates "backward" by screwing it in to richen the mixture by decreasing the air introduced in the idle well in the main metering block. Usually the main jet is selected for correct main metering supply, usually #64, and is leaned out, smaller number, for a higher altitude. The power valve channel restriction may be smaller for a slightly leaner power step. This restriction is NOT the calibration point where the power valve opens. The channel restrictions are calibrated otifices in the main metering block and are visible ehrn the power valve is rrmoved.
I know this because ive tuned my carbs on my original 6 barrel car....RS23V0A******* Plymouth GTX. Most 1971 models use this method because of increasing emission requirements.
Bob Renton