2 barrel 2 banger

[JohnsonM50]

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That is a reasonable idea and worth a try. Like delayed secondaries on a 4 barrel carb.

I remember an older Mercury (car) I was tinkering with. It was a stock 312 c.i.V8 with a 1x four barrel so I decided to replace the stock manifold and carb with a 2x four barrel set up. It definately was too much venturie area at the low and mid range if not careful with the throttle but was a stomper at the higher revs. The only set up that worked was the stock factory setup progressive linkage system. The front 2 barrels of each four barrel were operated together and the rear 2 barrels came in at about 70% open throttle.

Yes it is. Theres a number of ways I can go with this & Im pretty sure Ill hit on something sooner or later. Ill go with simple at 1st then go into trial & error with the different ideas based on results. Ill need to test in a barrel with a test wheel at 1st then see If I can get some real test tank time with a prop on. Otherwise tho Ill be going by ear, spark plug color & seat of pants oh & some on boat testing too

[zul8tr]

Yes it is. Theres a number of ways I can go with this & Im pretty sure Ill hit on something sooner or later. Ill go with simple at 1st then go into trial & error with the different ideas based on results. Ill need to test in a barrel with a test wheel at 1st then see If I can get some real test tank time with a prop on. Otherwise tho Ill be going by ear, spark plug color & seat of pants oh & some on boat testing too

Post results and pics

[Fastjeff57]

That's not how dual 4 barrels were normally set up. The rear of the two (since its primary barrels were nearer the center of the manifold) was what the motor ran on most of the time. The front carb came in about half throttle, with the secondary barrels of both carbs starting to open at about 3/4 throttle. The setup was bog resistant and allowed normal running at low speed. It even idled well, as Buick "Wildcat" and Mopar "413 Ramcharger" owners can attest.

Jeff (old geezer)

[JohnsonM50]

That's not how dual 4 barrels were normally set up. The rear of the two (since its primary barrels were nearer the center of the manifold) was what the motor ran on most of the time. The front carb came in about half throttle, with the secondary barrels of both carbs starting to open at about 3/4 throttle. The setup was bog resistant and allowed normal running at low speed. It even idled well, as Buick "Wildcat" and Mopar "413 Ramcharger" owners can attest.

Jeff (old geezer)

I never saw a 2-4 barrel 413 Mopar but got to drive several 426's, I worked at a Chry-Ply dealer & grabbed every opportunity I remember there being alot of pedal pressure near the bottom, not gonna floor that by mistake
This little outboard Im messin with is typically designed with the single carb slightly favoring the top cyl. [position wise] If I do set this up as a 2nd-ary Id use the top side as the primary.

[zul8tr]

That's not how dual 4 barrels were normally set up. The rear of the two (since its primary barrels were nearer the center of the manifold) was what the motor ran on most of the time. The front carb came in about half throttle, with the secondary barrels of both carbs starting to open at about 3/4 throttle. The setup was bog resistant and allowed normal running at low speed. It even idled well, as Buick "Wildcat" and Mopar "413 Ramcharger" owners can attest.

Jeff (old geezer)

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Well I said it was the stock factory setup and that's how Ford set up their dual 4 barrel on the 57 TBird manifold and carbs that I placed on the Merc. They were the high top Holly 4 barrels and the rears had vacuum activation . Wouldn't know about Mopar stuff. I suppose you could do as you suggest but because the Holly's had small primary venturies the car had good low end throttle response.

[Fastjeff57]

I was wondering if any olde time motorheads out there would catch my error: The 413 Ramchargers had its four barrels on a super long ram intake, one on each side of the motor, so this was NOT a progressive opening setup. I smartened up after making that goof, expecting someone would catch me on it, but...

A bunch of other factory cars also used dual 4 barrels, including Cadillac, Pontiac (421 Super Duty) Ford (427 Hi-Riser) and of course "She's real fine my 409!" All of THOSE were progressive setups. Honest!

Jeff

[JohnsonM50]

I was wondering if any olde time motorheads out there would catch my error: The 413 Ramchargers had its four barrels on a super long ram intake, one on each side of the motor, so this was NOT a progressive opening setup. I smartened up after making that goof, expecting someone would catch me on it, but...

A bunch of other factory cars also used dual 4 barrels, including Cadillac, Pontiac (421 Super Duty) Ford (427 Hi-Riser) and of course "She's real fine my 409!" All of THOSE were progressive setups. Honest!

Jeff

I have heard of the 413's ram intake. Id guess not that many made tho. Ive seen the 413 luxury version [Imperials] but a little before my time.

[Fastjeff57]

They were spectacular to see: The Carter AFBs were above and just to the outside of the valve covers! That's a loooong intake tract. I rode in a 300K (I think) with that engine on a date once, and the motor ran smooth as silk. The guy never jumped on it once, to my utter disgust!

Jeff

[Powerabout]

I was wondering if any olde time motorheads out there would catch my error: The 413 Ramchargers had its four barrels on a super long ram intake, one on each side of the motor, so this was NOT a progressive opening setup. I smartened up after making that goof, expecting someone would catch me on it, but...

A bunch of other factory cars also used dual 4 barrels, including Cadillac, Pontiac (421 Super Duty) Ford (427 Hi-Riser) and of course "She's real fine my 409!" All of THOSE were progressive setups. Honest!

Jeff

How about the Z28 302 dual quads.
how did they work?

[Fastjeff57]

Progressive also. I almost bought one of those cars, but the salemen at the Chevy dealership never heard of a Z28! (This was the Camaro's first year.) I bought a Firebird 400 instead--a dog.

Jeff