AVS 2 CFM???

Not 100% mechanical. They're a hybrid, just like a TQ. They are a vacuum mechanical secondary carburetor, since they have a secondary air door that regulates the amount of air based on venturi vacuum and spring preload. A true mechanical secondary carburetor would be a Holley style double pumper, with no secondary air regulation at all.

I bought a used 750 Eddy from a member here that had it on a 440. Bolted it on and my 20 Over 340 Eddy heads 10:5 to 1, 4 speed 323 gear loves it. Didn't have to jet it . No idea what's in it lol.

Bodyperson said:

I have a couple tree stumps and some mad fabbing skills. Probably make a tunnel ram.

Click to expand...

Sir, you have raised the bar! Time for me to break out the aluminum sheet, epoxy, and dig out the wood router!

The word secondary in the phrase 'Mechanical secondary' refers to the secondary throttle blades. Carter & Edel 4bbl, QJ & TQ are all mech sec carbs, as are some Holley carbs because the sec blades go to WOT when the primary blades go to WOT, connected by a mech linkage.
A Holley vac sec carb is not a mech sec carb because it's sec blades are not opened by a linkage from the pri shaft.

Bewy said:

The word secondary in the phrase 'Mechanical secondary' refers to the secondary throttle blades. Carter & Edel 4bbl, QJ & TQ are all mech sec carbs, as are some Holley carbs because the sec blades go to WOT when the primary blades go to WOT, connected by a mech linkage.
A Holley vac sec carb is not a mech sec carb because it's sec blades are not opened by a linkage from the pri shaft.

Click to expand...

Maybe it should be called an air valve secondary. You know... we could shorten it to AVS. . HA. Thanks for all of the responses everyone.
Pretty sure I'll go with the 800. Summit is all over the board on pricing all of these different AVS carbs.

I just ordered the AVS-2 650 cfm for my 340 Barracuda I hope I made the right choice?

Best throttle response avs 650,best top end power 800 .I have ran them all on 340s but you just can't beat a well tuned Thermoquad for all around performance.

I put a 650 AVS-2 on my mostly stock 340 and I don't feel that it was restricted on the top end. Throttle response is instant. For a mildly modified small block, I think that the 650 is the wiser choice.

I am running the AVS-2 on my mildly modified 360 and it is outstanding on the top end. Idle and throttle is excellent!

Bewy said:

The word secondary in the phrase 'Mechanical secondary' refers to the secondary throttle blades. Carter & Edel 4bbl, QJ & TQ are all mech sec carbs, as are some Holley carbs because the sec blades go to WOT when the primary blades go to WOT, connected by a mech linkage.
A Holley vac sec carb is not a mech sec carb because it's sec blades are not opened by a linkage from the pri shaft.

Click to expand...

That's why I said Holley style DOUBLE PUMPER. That's correct that the base plate is mechanical. However, I can tighten the secondary AIR DOOR so tight that it will not open until the engine is about ready to sling a rod. The secondaries on the AVS, TQ and later AFBs have VACUUM REGULATED secondaries. That makes them a HYBRID. You know what that word means, right? It means a mix of two things. They are NOT a mechanical secondary carburetor and they are NOT a vacuum secondary. They are some of BOTH STYLES. You need new understanding of carburetors. I don't really care what you "think" you know.

Read about "controlled secondary carburetors". They are NEITHER mechanical NOR vacuum. They are a mix of both. Now, go catch a kangaroo.

Vacuum or Mechanical-Secondary Carburetor? - Hot Rod Magazine

RRR,
I probably knew more about carbs & what the word hybrid meant since before you were born....
I wasn't going to mention this, another error by you, but your insulting & belligerent [ look it up ] language has prompted me to mention it.
In post #26, you refer to the 'hybrid [ AVS ] like a TQ' operates the air valve on venturi vacuum. Nope. For the very simple reason that the TQ [ QJ & Carter AVS also ] does not have secondary venturiis!!! So much for your much vaunted carb knowledge. Manifold vacuum is what opens the AVS [ or velocity valves in an AFB ], NOT venturi vacuum. Two different things.

Perhaps you should read the info you supply, such as the above link, before posting it. Then you might understand how these things work. Controlled secondary actuation of mech sec cabs in the above link refers to the AV operation, NOT the operation of the sec throttle blades.
The facts are very simple. Mech sec carbs, Holley double pumpers, Carter 4bbls, QJ, Edel are mech sec carbs. Holley chose to not use any type of regulation of sec airflow other than the linkage connecting the pri & sec throttle shafts. The other listed brands used the choke method. They are not hybrids, they are two different designs.

Now, go & catch some knowledge....