The Six Pack/BBL on the 440 is definitely legendary but does anyone have speculation on why Ma Mopar didn't offer dual AFBs? That video Of Nicks Garage using a 1959 dual quad setup (from a 413 or 426 RB?) on a stout 451 stroker B engine made me wonder. The engine made 25 hp less and 30lb ft less with the ancient dual quad as opposed to RPM intake and 750 Holley carb. So with the duals power dropped form 535 to 505 and torque from from 550 to 520. But the power loss would be less dramatic on the level a 440 magnum made stock. On top of this the 1959 manifold is a big open plenum single plane typical of the era- look at the Offenhauser dual quad manifolds. Offenhausers are of the same era tech wise (meaning the true dual plane design that came soon after would have been even more powerful). I remember a display set up circa early 1970ish by one of the Mopar greats (Dick Landy?) on a recipe for the 383 to go faster in the quarter mile. One of the items on display was the late 50s 383 dual quad intake and Carter carbs. Remember this was early 70s. But multiple carbs are always cool and two AFBs inline on a wide B/RB looks so right. Its an older video thats already been discussed here- but here's the link regardless.
https://www.youtube.com/watch?v=4wYHE3BlxlQ&t=334s

That would have made the 440 too close in horsepower to the 426 Hemi.

Probably because they offered the 6 pack. Wonder if any where available through direct connection/dealer back then? I have 383 6 pack set up from the era.

the test was not competed because Nick did not bolt a 6 pak on there to see what happens...

Six paks still rule, go get your hemi or your hellcat and let's go play.

Have a history lesson, no speculation required :

Remember Tom Hoover? He gave seminars at the NEHOA meets back in the 80's when these were just used cars; well they still are.
The seminars were held in the ballroom of the host hotel, The meets were always well attended & we had some interesting speakers beside Tom Hoover.
One stand out besides Tom but that is another story for another day Anyways Tom would show slides and talk- keeping everyone spellbound till at least midnight. btw there is vhs tape of these seminars out there in the hands of a former NEHOA member.

Anyways, the 1972 production hemi car was to be a 4bbl. Tom talked about the 1972 hemi development and what they were doing to pass 72 emissions
Dual quads were inefficient so they were going to single 4 barrel to pass emissions and improve driveability. Per Tom the 72 hemi production intake became the 4bbl intake sold by direct connection/mopar performance P4452034. Note the stove pipe connections for manifold heat. I don't recall other than the 72 hemi six pak was not being considered as there was no production hemi six pak intake, but they had tested prototypes and knew the six pak was more efficient feeding fuel to the 8 cylinders - ie faster than any dual quad set up.. He spoke of this more than once and there other informal conversations with him regarding the 6 pak hemi development etc. I have only been in few so called fast street hemi cars over the last 40 yrs that had a secondary hit like a six pak. Gary and Pam built a hemi six pak and Gary and I talked about it at length as he had spoken to Tom as well - see the six pak hemi pic.

And of course in the world of street racing the inevitable question would come up

Which is faster?? A dual quad hemi or six pak wedge?

Well according to Mr Hoover if it's a six pak hemi - it's faster.

Probably because by the time the 440 came out, and the musclecar era was ramping up, they had learned their lesson that dual quads don't really work well for street driven cars. The fuel distribution is very poor at low rpm use. The rear carb primaries are too far away from the front cylinders, resulting in uneven mixtures from the front of the engine, compared to the rear. Great for full throttle racing, but pretty bad in a daily driver. I think they installed them on the 426 Hemi mostly because it made the dual quads factory equipment, which made them legal for racing classes. The Six Pack however has excellent fuel distribution. The center carb is perfectly spaced front to rear, offers high vacuum for great throttle response and driveability, and the outer carbs feed evenly when all 3 are open. The Six Pack is a very good system compared to dual quads. Tom Hoover had planned to put the Six Pack on the Hemi too. They really should have. But by about 1970, they knew the end of performance cars was near, so they would not have bothered developing new performance parts and packages for factory built cars.

^^^^^^ hmm, a sixpac Rat Roaster..

Gary and I had lunch with Tom Hoover at Carlisle, and he told us what he remembered about the prototype Six Pack intakes for them Hemi. Supposedly there were two of the intakes produced and tested,but they didn't yield the emission standards they were hoping to achieve,but he was pleased with the performance of the Six Pack on the Hemi. He couldn't remember the horsepower numbers it put out.though. Gary had talked to Mopar Performance about producing the Six Pack intake manifold for the Hemi which they eventually did produce and offer the intake to the public.

Pic of '71 charger with MP six pack intake.

I can't say I am right but I always figured that the 4bbls of 50's early 60's era were kinda small on the CFM side and to make big power on big cubic inches, you needed two or more carbs. By the time the 440 came out there were also other big cube engines so the Carb companies started making bigger carbs for them. With bigger carbs available the need for dual 4's wasn't there for daily driver's. I doubt the Hemi or 6-PAck engines were ever considered grocery getters or you would have seen more than just the two or three 4 door hemi cars made.

That has always been my take but I am probably wrong.

The Edelbrock STR14-6 was the rat roaster intake for the 440 Sixpack application.

Almost every two piece B or RB intake made for NA applications have a history of back firing and breaking the tops
The Eddy STR were real dogs below 3000 RPM and then turned into real rocket ships
Not real conducive to good street manners

They work well with a big cam,a tall converter,and a lot of gear!

One of the prototype Hemi 6-Packs

Mike

Monterverdi High Speed was initially (1967-68) advertised with single (375 S) och dual carb (400 SS) 440 engines.
Claimed performance for 1x4 bbl was 375 hp @ 4600 rpm and 480 ft lbs @ 3200 rpm, for 2x4 bbl 400 hp @ 5000 rpm and 485 ft lbs @ 3300 rpm.
The dual carb alternative was discontinued after about a year so sales numbers should be marginal if any at all.

Probably the same reason there was no large port version, and no solid lifter version.

The better question is why did they not put the 440 CID short block under the hemi heads??? There wouldn't be any of this stupid debate about 426 hemi vs 440 6bbl, the hemi would have had the TQ like a 440 6 pack PLUS the top end of the hemi.

All it would be is a 1/16” bigger bore

See "ball stud hemi" if I remember correct.

That's what Stage V was doing before Mopar Performance was making new Hemi blocks.

The extra 14 CID would have been good for at least 15 LBS TQ and another 5 or 10 HP, it would have added a little more throttle response for the roll racing type, as close as people think they are now that would have easily tipped the scales in the flavor of the Hemi.