Can I make the secondaries kick in sooner?

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Killer6 said:
It's all good Dude, Hey, when the red X's start flyin'!! Lol! As long as WSUTARD understands what He's about to get into if decides it's needed, He has been warned, or just
throw a Quick-Fuel 650 on it & be done! OOOpps!! Did I say that out loud???
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Something about those f☆☆king red X's get my blood pumping. Lol
Cheers Bro.
 
RustyRatRod said:
That Edelbrock carburetor is a MECHANICAL secondary carburetor. That means when the throttle is WOT, ALL FOUR barrels are open, regardless of engine RPM, or vehicle load.

They are AFB carburetors. That stand for Air Valve Secondary. All this means is, the secondary barrels have an air door placed above the secondary throttle plates to regulate air flow. That air door DOES NOT control throttle plate operation, it only controls incoming air.

A vacuum secondary carburetor uses vacuum to OPEN the secondary throttle plates. The AFB is not such a design.
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Wait a second Rusty.

The AFB and and the AVS are not the same. The AFB stands for Aluminum Four Barrel and it has mechanical secondaries with the air valve above it.

The AVS stands for Air Valve Secondary and (IIRC) is essentially a vacuum secondary carb. I'll verify in the morning for sure but that's how I remember it.
 
You're exactly right. I got the names confused, but my description was right. Sorry bout that.

yellow rose said:
Wait a second Rusty.

The AFB and and the AVS are not the same. The AFB stands for Aluminum Four Barrel and it has mechanical secondaries with the air valve above it.

The AVS stands for Air Valve Secondary and (IIRC) is essentially a vacuum secondary carb. I'll verify in the morning for sure but that's how I remember it.
Click to expand...
 
Killer6 said:
It's all good Dude, Hey, when the red X's start flyin'!! Lol! As long as WSUTARD understands what He's about to get into if decides it's needed, He has been warned, or just
throw a Quick-Fuel 650 on it & be done! OOOpps!! Did I say that out loud???
Click to expand...
Don't worry, I'm not going to take this on. I thought it would be a twist or bend of a linkage to the secondaries. I would be trying to make this 1406 do something it wasn't really meant to do. If I do anything it will be to bump up to a larger carb or fuel injection and let a computer run my fuel. Funny enough, I would feel more comfortable messing around with the ECU than mechanical carb.
 
yellow rose said:
Wait a second Rusty.

The AFB and and the AVS are not the same. The AFB stands for Aluminum Four Barrel and it has mechanical secondaries with the air valve above it.

The AVS stands for Air Valve Secondary and (IIRC) is essentially a vacuum secondary carb. I'll verify in the morning for sure but that's how I remember it.
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Almost, AFB's & AVS's both have the Air Valve above the throttles, but the AVS(& Thermoquad) Air valves are spring loaded instead of counterweighted, ADJUSTABLE .
So is the Roachmaster Quadrajunk, which actually is a decent carb tuned correctly. As per RRR, correct description, right acronym.....................wrong words.........
One of the gang in My sphere put a dual-quad intake on a 440, w/(2) AFB style
carbs, they were too big and the engine stock enough that the initial punch on
the loud pedal had enuff signal to flop 'em all wide open, then fall on it's face.
Then repeat, ........WAAHH.....WAAHH....WAAHAHH....WAAAHHAAAAAAAA!!!!
 
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More compression will pull them open faster too.

I like the DPs cuz :
I can open the secondaries at will,and blow the tires away whenever I want to.
Or I can just roll into it, keeping it on the edge.
Or I can just drive it like a sane person might.
But where's the fun in that? I like to let the dragon roar!!!!
What?...It's only a 367, how much roar can it have?
Oh yee of the 8.0Scr crowd, and the stock TCs and the 2.76ers.
I almost feel sorry for you.
I'll tell you a secret; it's all in the TM;Torque multiplication. I can tell you that 3 gears to 65mph if you can make it hook is all a streeter with a little engine needs, to show many, many others the way home. Even just two,with a bit bigger engine.
But if you just wanna have fun, then a 10/1 starter gear, will get you a ton of smiles.
But I gotta warn you, The more TM you have, the less "kick" you will feel, cuz the engine will be staying "on the pipe".
To feel the kick, just over rev it a tad. If it goes out at 200 HP and it comes in at 250 POW! there's your 50 hp kick.
 
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You know, im having second thoughts on this Edelbrock thing.
Edelbrocks secondary butter fly's or throttle plates "are" mechanically opened, but the secondary function
is vacuum controlled, or fed by vacuum . This is telling me that this is a vacuum secondary carburetor.
Yes-No ?
 
I had a 493 tunnel ram with Eddie carbs had one set of secondaries door has a 3/8 hole drill in each weight and the other set I removed one weight completely for racing
 
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Johnny Dart said:
You know, im having second thoughts on this Edelbrock thing.
Edelbrocks secondary butter fly's or throttle plates "are" mechanically opened, but the secondary function
is vacuum controlled, or fed by vacuum . This is telling me that this is a vacuum secondary carburetor.
Yes-No ?
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Nope. The secondaries are mechanically opened, therefore it is a mechanical secondary carb. The difference is this: on a Holley VS the secondaries only open with vacuum. Also, since the AFB and the AVS do not use an accelerator pump on the secondaries they use the air valve to make sure the air speed is high enough to get fuel flowing through the booster before it opens.
 
Johnny Dart said:
You know, im having second thoughts on this Edelbrock thing.
Edelbrocks secondary butter fly's or throttle plates "are" mechanically opened, but the secondary function
is vacuum controlled, or fed by vacuum . This is telling me that this is a vacuum secondary carburetor.
Yes-No ?
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Re-read My post #15, air-valves are actually like variable venturis in a way, the throttles are
wide open below. The restriction is ABOVE the idle area and can boost fuel signal and maintain
a favorable velocity IF it is calibrated correctly, it is directly depression responsive, so in that
way it is vacuum controlled.....but it is not a venturi vacuum operated throttle system. The
reason I don't like the counterweight system is the lack of adjustability, that simple.
 
WSUTARD said:
The car runs great and pulls great. When I floor it I can feel the secondaries open and it pulls like a bat out of hell. However, I was thinking it would be better if I could get them to open earlier on the pedal throw, say at 75% pedal vs 100% (I dont know exactly when they open on the pedal, only that I only feel them when I floor it)

Is there anyway to do this?

Am I making things up?
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Carb 101 say's it BOGGS.
 
yellow rose said:
I knew you knew Rusty. I figured it just slipped by you and I didn't want someone getting the nomenclature jacked up.
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Thanks. You know, gettin old has both its drawbacks and advantages. lol
 
Find two unwanted eddy carbs like yours remove one weight from the doors drop them in your carbs at the track and try it out then come back and tell me what you think
 
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