[HWYSTR455]

I don't think the secondaries are adjustable on any of them, but could be wrong:

https://www.edelbrock.com/pub/media/...ers-manual.pdf

I remember back in the AFB days, you muck with the weights and you are going in the wrong direction, you can get lost. The objective is to manage vacuum during the throttle opening range. That can be done with tuning the primaries and secondaries with jets, rods, etc. If it's too fat, vacuum drops off, too lean, and vacuum is higher. Have to find the balance, or that's how I remember it.

I can't remember if there are different plunger springs, but I don't think so. I do remember some folks trimming them or stretching them out/shimming pocket, to fine tune. That too, you can get lost.

The biggest reason I went away from the AFBs is due to the side bowls, high G turns it could flood. Holleys generally could have flood issues on hard acceleration/braking. In my case, it was easier to deal with the acceleration/braking thing. So I switched. But I had a 2x4 AFB setup working very well. (on an Offy dual plane 360)

Original/old body castings can become porous, and actually seep through the body. Late in production, Carter, who may have actually been already bought out once, offered coated bodies, black, called Black Stallions. I at one point upgraded to those, and many of the porosity issues I had were resolved.

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