Carter AVS tuning?

[MopaR&D]

I have a Carter AVS carb #4640 that I'm trying to get running on an otherwise bone-stock 440 in a '72 Polara. It stumbles/bogs pretty badly when I free-rev it which I think is due to numerous vacuum leaks, but I still need new straight metering rods and possibly jets. Will the Edelbrock calibration kits (rods/jets/springs) for Thunder AVS carbs work with my old Carter or are they different? Do they also interchange with AFB/Performer metering rods and jets?

 

[rumblefish360]

Heres the deal with OE AVS carbs, the rods are 3 step and slightly longer. The covers on top are slightly domed for this reason.

You can take the flat covers of a AFB, Edel. or Carter or OE carter and swap them on and use AFB 2 step rods from Edelbrock, a old Carter strip kit from ethier the OE / MP strip kits or newer ones or the OE carbs.

The difference in carbs, from OE AVS or AFB and the newer ones mostly seen by Edelbrock are a revised fuel curcuit for use with performance cams so they'll idle better and accel off the line without leaning out badly.

Once you find the vacuum leak, if any, move to the pump shot system on the carb. Again, this unit ethier may be drilled out or swapped with an Edelbrcok unit. Make sure the ball chack or needle check is installed under it.

 

[MopaR&D]

Thanks rumble. I noticed too when I had the carb apart that it had small open passages going from above the throttle plates to the baseplate, I'm guessing as an attempt to lean out the overall mixture with an "intentional" vacuum leak. Should I try to block those off or do they not make a big difference?

 

[rumblefish360]

I'm not sure what passsages exactly your meaning. The one I was talking about was the one under the pumpshot cluster. Can you post a picture?

Otherwise, no is your answer. Lean it out through rods and jets.