Looks as if Edelbrock have just released a 500cfm Carter AVS. This is a significant development; previously the smallest AVS they offered was 650cfm. I'm hoping 440_Magnum will chime in to give his usual excellent discussion of why the AVS is better than the AFB. I am a little curious as to why Edelbrock refers to it as "Adjustable Valve Secondary" (AVS originally stood for Air Valve Secondary, as I understand it). Wonder if this is just a terminology difference or something more important.

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Too many people who were born on third base actually believe they've hit a triple.

Interesting! That should be a GREAT carburetor for small-displacement engines. The AVS is already far, far more forgiving of "over carburetion" than and AFB, so a small AVS on a slant would be even better than a small AFB. For example, the Thermoquad operates very similarly to the AVS, and the factory offered a >700 CFM TQ as standard equipment on copcar 318s, even though thats gross over-carburetion for that little engine. Because of the air valve design, they worked just fine and I run one on my 318 as well.

I think the name change plays up to the strength of the AVS, and does not reflect a design change. The air valve *is* adjustable, which is what gives the carb so much flexibility. Later AFBs also have a sort of air valve, but it is a) below the fuel delivery ports, not above, and b) not adjustable. All it does is act as a pseudo-throttle on the secondaries, whereas the air-valve on an AVS acts as an enrichment aid since its above the fuel delivery points and is very much a part of tuning the carb to get rid of flat-spots and stumbles.

Now if Edelbrock would just lower the price on their Thunder Series AVS a couple hundred bucks.... :-/

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Interesting. Loks like you can get the new 500 CFM AVS for $269.99 at Jegs under the factory remanufactured carbs section. Its only $10 more for a new one so you may want to buy a new one anyway.

I think this is where Dennis W. would go "I told you so!"...

Somewhere in a long ago post he had recommended this option, and as Carter goes the AVS would be a real nice one to plunk on a slant in 500 cfm...

Looks like I'll have to add it to the BD list and try it on the HPak for kicks...


thanks,

-D.Idiot

Reed can you post a pn? I didn't find a 500 cfm under their rebuilt carbs at jegs, and only saw the new ones for $350.

Or are you refering to the performer carbs? http://tinyurl.com/b4wj9

What's the difference?