my 1st 340....yea

This is not true. The 4966s AVS is the same cfm as a 340 or 383 AVS. To get the large AVS you need to find a 440 High Performance AVS such as a 4640s they run about 750 cfm as opposed to the 630 cfm of the smaller primary bore AVSs.
You're right.
I thought I had the 4966S, but actually have a 4429 with the 1-11/16" bores from a 440 Magnum/Super Commando.

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