Which intake manifold

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Mojoe9955

Mojoe9955

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I'm not sure what I'm looking for, but I want to up the performance of my Slant Six. I'm not sure what is entailed but I assume it involves intakes and headers. Which of these intakes is a good choice? I have a Holley 4412 carb and the 2 barrel intake.
Thanks

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How do you plan on using the car? Any other mods? Stick or auto? Rear gear? Etc? The 4412 is kind of big for street diving on a close to stock engine. The barrels are large, and don't have much air velocity at low RPM, so drivability suffers. For a almost stock engine use the Mopar 2bbl manifold, and a smaller 2bbl carb. That manifold did have some issues with porous welds, but if you paint it with epoxy paint, that will cure any possible problems.
 
I may be in the minority but if it is otherwise stock I would go with the 2v intake.
 
I agree with the two barrel intake. I also agree with Charlie that the 4412 is too big. That's 500 cfm. I have a 450 quick fuel four barrel on mine and I consider it pretty heavily modified. Over 10:1 compression, .465 lift 250 @ .050 duration on a 108 LSA. I think the 4412 would be too big for an engine that was much milder than that. I would look at the 318 Carter BBD two barrel. It would probably be much better suited. Maybe even the stock Super Six carburetor if it's going to be really mild.
 
The car came with a mainfold like that and the carb. It's seems like it's just a stock 225. It actually runs pretty good like it is, it doesn't seem like it gets good mileage though.
 
Mojoe9955 said:
The car came with a mainfold like that and the carb. It's seems like it's just a stock 225. It actually runs pretty good like it is, it doesn't seem like it gets good mileage though.
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It would run better with a different carburetor I do believe.
 
I just did a 1bb to a super 6 2bbl with a BBD. great upgrade on an otherwise stock motor.

like RRR said, for 4bbl you're gonna need a cam and compression.
 
So the nasty, looking 2 barrel is actually a late model aluminum Super Six intake?
 
Mojoe9955 said:
So the nasty, looking 2 barrel is actually a late model aluminum Super Six intake?
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Late model? 76 I think was the first year for the Super Six. Almost 50 years ago? Late model? LOL
 
Back in the way back machine, Holley had a small spreadbore 4 barrel. They called it the economaster. It was like 450 cfm. Something like that may work well on the 4 barrel intake. But slants are such pigs stock I cant imagine anything larger working well.
 
HankRearden said:
Back in the way back machine, Holley had a small spreadbore 4 barrel. They called it the economaster. It was like 450 cfm. Something like that may work well on the 4 barrel intake. But slants are such pigs stock I cant imagine anything larger working well.
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I have one. lol
 
RustyRatRod said:
They probably work really well. Although they are a spread bore, they ain't spread "very far". lol It'd be good on a slant 6.
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they surprisingly do!

I had a rolling test lab 69 cuda for quite some time and I'd screw around with different intake and carb combos on the tired *** stock 318-2 that was in it.

the 6904MB is a 450 and has mechanical secondaries which played nice with a old school performer. nice throttle response and drivability.

like you I have one holding down the shop floor too...
 
btw, if you get the super six set intake a BBD out of pretty much anything will bolt up to it. you'll want to replace the mounting studs if you're running the thicker 3/8" (I think) spacer/gasket, but be mindful of the length so they don't foul on the carb body. you'll have to modify the choke or swap it to electric.

also, you'll want the throttle linkage and kick down-- hopefully they have it. not a deal breaker, just makes it a little more fiddly to install.

if they weren't much I'd consider picking up both
 
There were 370 cfm 4 bbl carburetors, but hard to find today and pricier than a more common 500+ cfm one. In theory, a small 4 bbl carburetor could give better drivability and mileage than a 2 bbl, since at lower power (steady highway driving) you run off just the primary bores which can be smaller than in a 2 bbl. True, the Holley Economaster line might be a good choice. Those were sold aftermarket starting in the late 1970's gas-crisis and generally were smaller cfm than the OE carburetor for the same application. I think they even made a 1 bbl version. You occasionally see them on ebay. If you choose to use the Clifford 4 bbl, I think you need a few other special parts, like a kickdown system which Edelbrock sold (google). While at it, Edelbrock also sold an aluminum valve cover for the slant which is slick, especially if painted a wild color.
 
BillGrissom said:
I think they even made a 1 bbl version. You occasionally see them on ebay. If you choose to use the Clifford 4 bbl, I think you need a few other special parts, like a kickdown system which Edelbrock sold (google). While at it, Edelbrock also sold an aluminum valve cover for the slant which is slick, especially if painted a wild color.
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I have a 1bbl economiser on my 64 Valiant. It did help fuel mileage slightly, but limited RPM a lot. As for the clifford intake, be aware that the stock exhaust manifold will not work.
 
I'm not sure what I actually have on the car now intake wise, but talking here I think it is a cast iron Super Six. It is missing the stock linkage and I think I read that it needs a shorter throttle cable. It also has some sort of Loco kick down cable and adapter. Seeing that it all works as is and the Clifford needs many more pieces to come up with, I think I'll save the money now and try and find a smaller carb.
Thanks
 
when I was driving my Slant6 70 Challenger as a daily driver. I too wanted to step up the performance value of the Dodge. Since the engine was a 1977 p-nut plug replacement engine for the original. I decided to go the route of a cast iron Super Six manifold with a BBD 2bbl off a 318. I had a choice of an aluminum 2 bbl and an Offenhauser 4 bbl intake but I chose the cast iron factory intake for less daily driving problems. This was about 25 years ago, I think I made a good choice.
 
Mojoe9955 said:
I'm not sure what I actually have on the car now intake wise, but talking here I think it is a cast iron Super Six. It is missing the stock linkage and I think I read that it needs a shorter throttle cable. It also has some sort of Loco kick down cable and adapter. Seeing that it all works as is and the Clifford needs many more pieces to come up with, I think I'll save the money now and try and find a smaller carb.
Thanks
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post up a pic of what you've got. it might be that you've got all the jam stuff it just needs some love to work right.
 
Mojoe9955 said:
I'm not sure what I'm looking for, but I want to up the performance of my Slant Six. I'm not sure what is entailed but I assume it involves intakes and headers. Which of these intakes is a good choice? I have a Holley 4412 carb and the 2 barrel intake.
Thanks

View attachment 1716009412

View attachment 1716009413
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If you really want something different I have an adapter that will bolt to a four barrel manifold onto which you can mount two two barrel carbs
 
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