Edelbrock AFB vs AVS

Here is a great write up from on own Triple R

The 1400 series is bases on the Carter AFB. They were decent carburetors. But the Carter AVS was a big step up in improvement over the AFB.

The 1800 series is based on the Carter AVS. They are considered superior to the AFB for several reasons but the number one reason is the smoothness of the transition into the secondary side of the carburetor.

The reason for this is unlike the AFB style carburetor, the secondary boosters are located under the secondary air door instead of on top of it. This allows for a much more accurate air signal to the boosters and results in a much more smooth operation of the secondary side.

Also another great benefit is the AVS style carburetors, much like the Thermoquad, are a vacuum secondary design. This means that they are much more forgiving in an over carbureted situation and that one size carburetor will work on a variety of engine sizes.

Since the AVS style carburetors will only flow what the engine demands, that means they will never "over carburete" the engine. Rich primary conditions can easily be adjusted out, since they have an almost infinite adjustability with springs, metering rods and jets.

IMO they are probably the dead best carburetors out there for a street or street/strip car. Repair parts are cheap and plentiful. It's not like trying to find a needle in a haystack tuning kit for a Thermoquad, because all kind of tuning kits are available.

IMO, the 1800 AVS Thunder carburetors leave the 1400 series in the dust. That's my story and I'm stickin to it.