I have been running a dual quad setup (Eddy 600's) on my Charger for a long time with no real problems. It's a basically stockish 440; Stealth heads, .030 over, 282/292, .465/.488 cam, shorty headers, 4-speed. It's been very reliable and maintenance free.

I'm wondering what real improvement in performance I would get with a correctly set up single carb. I noticed on my buddy's '68 440 Charger with a single Holley, it really has great throttle response and power.

I really like the visual impact of the dual quad at shows and such, but am I leaving a lot of power on the table?

Opinions?

This lacks a little low end response but from about 3K up it won't quit.

The duel on my 340 made a LOT more power, but tuning headaches caused me to pull it off a year later.

-Daty

I had a dual carb intake on my 383 with Carter 500's for years. It ran ALOT better when I took it off and put on a Torker with a 750 Carter. However the visual appeal was MUCH better with the dual carbs...

I've had my share of SmBlk and BBlk engines running single fours and quads,...sure they were all fun, had their pros/cons...if you want the best of both worlds run a 6 pack, properly tuned, it represents the best of street-ability to awesome multi carb performance


Mike

Any properly setup will provide the power you want be it single quad, dual quad, 3 deuces whatever. Find someone that can tune your setup and you'll be happy. The intake itself maybe the limiting factor, i.e. single vs dual plane. You are running a dual plane, a singlr 4 on a sinngle plane will make top end power, you will have it beat on torque. For all out power you cant beat a dual quad on a nice single plane high rise, check out the top classes and pro stock. Of course I'm really prejudiced.

Generally speaking on a street engine a good single 4 will trump the duals in HP and drivability, but as stated, lack the visiual appeal of dual 4's. That said, regardless of it being a big block or small block, if it's 500 cubes or less and a true pump gas street engine and you want the most from a set of dual 4's buy the smallest cfm carbs available from the desired brand (Holley, Carter, etc.) and start from there, you'll likely find that you'll get the best throttle response, milage, and overall performance.

Try a tunnel ram with CORRECTLY TUNED CARBS. You won't go back to a single 4 bbl. Dave

A 605 Hemi is entirely different story!

On a 440 the Edelbrock is much better than the Offenhauser. The Edelbrock properly tuned will be hard to beat on a street vehicle-real world street driving. I believe the rpm range as stated from Edelbrock is idle to 6000Rpm with 2 of their carbs.

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Doesn't make a difference if it's a 605 or a 440. PROPERLY TUNED is what makes the difference. Most people are usually to lazy to go through all the work to get them right. Dave

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I don't dissagree with you on that, my point was that for the average street engine (500 cubes or smaller) the cfm requirements to feed a smaller engine are less and most will find it easier to get the best all around performance from a single 4 barrel. That said for ultimate performance a dual 4 setup (with carbs sized appropriately for the engine) will likely result in the highest overall HP if tuned properly. But as you've noted, most people are either too lazy to go through the proper tuning efforts to get there or simply don't know how to do it.

The carb/intake picture I posted above is a complete setup from a 62 300H.Cam is old Crane Commander,motor is .030 over 440 with Ross flat top's,zero deck,rejetted origional 62 carbs,recurved factory tach drive dual point, ported 906 heads and complete 3" Max Wedge exhaust.Lacks a little at low end,the old dual plane factory intake isn't the greatest but for something that I wanted to be drivable it works to suit me.Get's around 16/17 mpg and top end that just keeps going.And,I don't have a fuel problem as it runs on 80% AV gas.

MEH!

I had the RPM Intake (Still do) with the single 4 750cfm. I had good response. I could put my foot down and move. I started collecting the Dual Quad parts in 2002 and I finally put it on 2 years ago....I love it....I mean really LOVE it. I have dual 500cfm Eddy's. I can cruise with the GV overdrive....4th gear...2200rpm...28" tire...3.55s and the one 500cfm carb is open. My A/F meter hooked up and good numbers. I edge my foot a little further and you can feel that second carb opening, OD switches off, passing gear and more pedal and you have the full 1000cfm. My rear tires get squirrely and it really puts your cheeks in the seat. I got about 18mpg with my RPM/750 setup.....I haven't crunched the numbers (because my fuel gauge can't read right) on the new setup but I would expect the RPM/Dual 500s are putting at about 12mpg at the moment only because I installed my RPM heads and haven't dialed the engine back in with the A/F meter because I still have yet to install my headers...

I have a 505 I am building but for the meantime...the induction setup on this 440 will keep my happy for a few years to come before I decide to build my roller motor

Around 1995 in the Chrysler Power magazine they featured a man with a 71 ish Charger. It was a street and bracket car. He ran the Edelbrock CH28 and two Edelbrock 600s. He said his car had ET'd better with a big Holley and Weiand Team G but the streetability and low end was better with the dual quads. Dont run duals on the street for the best performance because it was the 40s 50s and early 60s were multiple carbs were better performing than single. Run the duals because they look great and compliment a muscle car better than anything else!!!!!!!!!!!!!!!!

I have had a car with both a single carb. on a dual plane intake and a stock single plane dual car. intake with stock carbs. with progressive linkage. The single four combination drove a lot better than the dual four barrel did until I hooked the dual carbs. up so they both opened together, not progressively I have done that on several other cars wiih good success

If you want to throw a little science at the question you can do the math and find out what your engines CFM requirements are (or should I say, SHOULD be based on this formula). Once you know you can look into what size(s) your carbs should be to best match the number. I've found that it's a pretty good tool. The wildcard is that cfm ratings of carburetors are really not that accurate or consistant accross the different brands, i.e. a Holley 750 may flow more than a Carter 750 or vice versa, etc. The other variable is manifold design and fuel distribution variables between intakes as well as carb designs.

CFM calculator

Thanks for all the input guys. Sounds like I can make this work, but I don't know if they are tuned to the ultimate performance. I don't have a A/F ratio meter, so I guess it would be hard to do. Though I know how to set the idle using he vacuum meter.

I'm running the Offenhauser intake, which I don't like much because the carbs are spaced so far apart on this manifold compared to others, that I can't use the nice Edelbrock progressive linkage setup because it's too short to reach carb to carb. I'm using the cheapo rod/set-screw stop style. It works, but looks cheap. I have it set up so the secondary carb starts to come in after about 20 degrees of rotation of the primary throttle. Then they both reach full throttle at the same time.

I have read the plugs and they look great (light brown) except for two that look almost brand new (no color or deposits). I haven't looked at them for 800 miles or so (the engine only has a little over 1000 miles on the rebuild), they may be different now. Because of this and the fact that it seems to run well, I assumed that they were pretty close in tune, but maybe not. I will do a little research and see if I can get them closer. I've read the tuning instructions in the Edelbrock manual a few times over and for some reason my brain isn't completely grasping the whole theory of the metering rods and all the functions. The instructions seem a little confusing to me. Maybe I'll call their tech line and see if they can explain in layman's terms.