Thread: dual 4 barrels

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Got a question for all you who have run dual quads on a SBC. I have a 305 bored to 315 with a small cam 218/224 dur. @.050 and I'm running a 600 cfm edelbrock carb with a dual plane intake manifold. I have 1-5/8 headers with a MSD coil and Distributor. Rear is a 9" ford with 2:76 gears. I traded a used 3 deuce set up for a polished edelbrock intake with dual 500 edelbrock carbs. I would like to run this on my engine using only one carb but have it set up for progressive linkeage where I would have the second carb only open it's secondary's part way. I love the killer looks of a multi carb set up and it's not just for show as I put on about 2500 miles in the summer. Would this combo work or am I asking for problems?

It would seem like 390CFM carbs would do better but as long as you put enough slack in the second carbs progressive linkage, seems like it should work ok.

Go for it. Dual-quads are my favorite. I doubt that you'll ever get into the secondaries of either carb, the primaries of each carb should fulfill the needs of the motor at WOT. I'd run the rear carb as the primary carb and set up a sliding rod arrangement to pull the primaries of the front cab in at about 75%, so that the throttle blades of both arrive at WOT at the same time.

There's nothing quite like the sound of 2-4's suckin' for all they're worth

i have a offy 2x4 intake edelbrock,carbs, you might be overfueling a bit, on a 305,but jet it down a bit, should be o.k
i set it up to run off the front choke, complete with an electric choke,back carb starts opening up at about 2800 rp's

yes they look good .the thing that i can think of is that the idle may be a bit hi but could be tune in. that is the one thing that may give you some troube the more cfm on the small engine may be hard to turn down them all the way down but can be work out go for it

Carbs are a little big for the engine a cam you're running, but it'll work if you jet the primary carb back. If it were me, I'd run the back carb as the primary, gut the front carb and run a slider type linkage from the rear to the front so that you can determine when and if you want the front carb to come in. I ran a setup like that on the sbc I had in a '36 coupe.

I agree Tech, you will probably do fine with the set up. He and NTFDAY also right about the linkage set up.

Set the rear carb up as the primary with the functional choke, and either disable the front carbs choke or remove it.

Thanks for the info Thats how I was going to run it with the slider type linkeage. Both carbs now have electic chokes and I will pull one off. Might lose some of my HP and torque but what the hell. It will still run good and the sound like tech says of both openiing up will justify the change over

What about running a stromberg 97 EFI setup, where the carbs are gutted and have the injectors inside, you would have the look, with the reliability of EFI

Matt I was lookiing into that but I got the better part of a deal with these dual 4 barrels, so I'll give them a try.

I run a couple of Carter 500 cfm's on a 462" Buick.
Granted, a bigger engine than your Chevy, but it's a nice setup.

Straight linkage is used and secondaries are not a problem with the big engine nor will they be with your smaller engine.

Carter/Edelbrocks air valve open to what is required for the engine.
Which is to say, do not adjust the carbs - or secondary carb if progressive linkage is used - to limit the secondary throttle opening.
If you do, you'll also limit the primary opening due to the primary and secondary throttle blades operate in unison and rely on the air valve opening for proper airflow.

I don't see anything wrong with using progressive linkage as long as you build a good one or buy a good one.
Edelbrock - I believe - has a good one.

Some of the cheaper progressives, especially those on triple 2 bbl setups leave a lot to be desired and some of them in fact are dangerous to my eyes.

With the big Buick running a 284-292 adv. duration cam and the straight linkage dual quads it will idle at 600 rpm all day long.
Throttle response is excellent as well.

You'll have to pay a little more attention to the setup when using dual quads on a smaller engine, but it's not the black art that some make it out to be.

I bet those dual quads looked real nice on that big buick engine. What did you have it in?

Originally posted by chevy 37
I bet those dual quads looked real nice on that big buick engine. What did you have it in?

32 Roadster.

Here tis, home-made fuel log, home-made air cleaners, home-made linkage etc.

Now running a 750 Carter on an Edelbrock Performer with a milder cam.

The carburetion and big cam are going into the car on the next post.

A slightly different view of the fuel block and linkage.

Counting fittings, aluminum stock, Heims, stainless rod, perhaps $50. invested in everything.

And here's a pic of the new project . . . 31 A roadster on 32 frame rails.

Also a 455 Buick which will end up 462" and right around 540 # torque.

At 2200# total vehicle weight, should be fun....