best hi flow ex manifold/drivers side

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Rapid Robert

Rapid Robert

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63 dart stock car. 360 SB. what is the best flowing ex manifold to search for? has a thin shaft aftermarket steering column. thank you for your time. RR
 
Big bucks if you can find one.
A cheaper alternative would be the '92-93 Magnum manifold that has a larger outlet diameter than the later ones, casting numbers 617/618. Even the standard Magnum manifolds don't give much up to the larger bore ones or the 340 manifolds.
They all will take some horsing around to get them to fit an early A (even the 340 manifolds need the column sleeve cut back) but it can be done. Here's a thread on doing it with the Magnum manifolds:
YES 5.9 Magnum manifolds work in early A bodies. Here is exactly how!
And BTW, for anybody reading this in the future; none of these work with power steering.
 
There was a manifold shootout a long time ago in one of the mopar magazine I think, they found one of the magnums and one of the 340's gave the best result, can't remember which side was which, but there wasn't a huge difference between the 340 & Magnums and even the 360 ones too.

Here's another shootout, no magnums just 318/340/360 & some headers

https://www.motortrend.com/articles/mopp-0307-installing-exhaust-headers-into-300hp-crate-engine/

Horsepower
RPM318360340SHT1 58tti1 34
2500186185187189187189187
3000223223225226228228226
3500269271272276280281279
4000299301306307314318312
4500311313315321319326321
4600311314315320317327319
5000303304308315312316311
5400281291289295282296289
Legend318:Stock '69 A-Body exhaust manifolds with 24-inch extensions360:Stock '77 360 iron log-style exhaust manifolds with 24-inch extensions340:Stock '70 340hp exhaust manifolds with 24-inch extensionsSHT:Hedman 151/48-inch-tube shorty headers with 24-inch extensions 1 58: Hooker Competition 1 58-inch ceramic-coated header tti: Tube Technologies Inc. 1 58x1 34-inch chrome step header 1 34: Hooker Super Competition 1 34-inch header; bare, uncoated
 
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I believe if you have a magnum manifold and a die grinder, you could have healthy flowing manifold.
 
Professor Fate said:
Big bucks if you can find one.
A cheaper alternative would be the '92-93 Magnum manifold that has a larger outlet diameter than the later ones, casting numbers 617/618. Even the standard Magnum manifolds don't give much up to the larger bore ones or the 340 manifolds.
They all will take some horsing around to get them to fit an early A (even the 340 manifolds need the column sleeve cut back) but it can be done. Here's a thread on doing it with the Magnum manifolds:
YES 5.9 Magnum manifolds work in early A bodies. Here is exactly how!
And BTW, for anybody reading this in the future; none of these work with power steering.
Click to expand...
I dunno that just doesn’t look safe, that motor would have to be chained down because if it shifts up it’s going to push on the steering shaft. Wish there was some better picture cause it looks like it’s resting on the manifold……….
 
I don’t believe any of those manifolds will fit into an early A body and clear the steering shaft and frame rail on the drivers side. Maybe a post from @Treblig can shed some light on this.
 
good info & actually I have one of the early large port magnum manifolds but it slightly touches the top of the steering box to where it will not seat flush to the head ex ports & I have already slotted the box mounting holes so I could lower the box (& a guy posted that this would affect bump steer (dont know what that is, I need to Google it) but handling on the circle track is everything. I could raise the eng a hair but the low profile aircleaner is very close to the hood. I could maybe hammer the center of the hood out a bit where the air cleaner is to gain some clearance then raise the eng (sounds like a good plan). I could lower the k member to lower the whole shebang but that might affect steering even more than lowering the box but that's way too much work. I'm thinking if i can grind the bottom of the manifold & maybe grind a very slight bit off the top of the steering box that that might do it but it feels risky. On a side note I remember a vid from way way back where the guy put some battery acid (iirc) in the manifold & let it sit then dumped/rinsed it & the CC capacity was significantly bumped up. this is where I'm at so far & the racing steering column is a skinny shaft. RR EDIT the magnum mani I have sure looks like an excellent piece but I there is a mani that will fit as is it would sure solve this pressing issue. MORE EDIT I just perused the thread mentioned & professor Fate that is dynamite info, thank you!
 
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Rapid Robert said:
good info & actually I have one of the early large port magnum manifolds but it slightly touches the top of the steering box to where it will not seat flush to the head ex ports & I have already slotted the box mounting holes so I could lower the box (& a guy posted that this would affect bump steer (dont know what that is, I need to Google it) but handling on the circle track is everything. I could raise the eng a hair but the low profile aircleaner is very close to the hood. I could maybe hammer the center of the hood out a bit where the air cleaner is to gain some clearance then raise the eng (sounds like a good plan). I could lower the k member to lower the whole shebang but that might affect steering even more than lowering the box but that's way too much work. I'm thinking if i can grind the bottom of the manifold & maybe grind a very slight bit off the top of the steering box that that might do it but it feels risky. On a side note I remember a vid from way way back where the guy put some battery acid (iirc) in the manifold & let it sit then dumped/rinsed it & the CC capacity was significantly bumped up. this is where I'm at so far & the racing steering column is a skinny shaft. RR EDIT the magnum mani I have sure looks like an excellent piece but I there is a mani that will fit as is it would sure solve this pressing issue. MORE EDIT I just perused the thread mentioned & professor Fate that is dynamite info, thank you!
Click to expand...
Don't some mill some off the manifold flange to gain room ? Angle mill it ? Not sure kind of remember people doing/saying that.

I wouldn't do any engine or suspension moving to make it fit, what are we talking power wise an hp or two, I know all the little gains add up, but I wouldn't do anything other than mod the manifold to fit.
 
cosgig said:
I don’t believe any of those manifolds will fit into an early A body and clear the steering shaft and frame rail on the drivers side. Maybe a post from @Treblig can shed some light on this.
Click to expand...
I fit an early 340 exhaust manifold on the driver's side by switching to a power steering column and using an adapter (Firm Feel, etc) to hook it to the manual steering box. That put the joint far enough back to clear the manifold.

I ran the outlet pipe between the torsion bar and the frame. Two and a quarter inch pipe. Barely fit, but it did. Larger pipe probably would not.

Have no idea if a power steering box would work with 340 manifolds. (I have TTI headers now.)

1713468156585.jpeg
 
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I had thought about a bit of angle milling to raise it. I do have a thin aftermarket steering column (actually just a thin shaft) & the coupler is narrow too so I might be good there. if a bit of grinding on the top of the box/bottom of the manifold & maybe a bit of angle grinding doesn't cut the I'll likely have to raise the engine (& I am using using OE 273 mts with the ear welded on the one side & the OE tall/thick black rubber biscuits) OR cough up the bucks for an early 340 manifold like Professor Fate originally posted & 2&1/4" exhaust is dictated. RR
 
Robert, if you can find an A body drivers side manifold from a 72 and up 340 or 360, it is the same thing as the early 340 Hi Po drivers side manifold except that it has tabs cast on top of it to hold a heat stove for a pipe running up to the air cleaner. It has the same 2 1/4 outlet as the earlier Hi Po's. They are usually cheaper than early ones. There's some for sale on here, but I suspect they are 318 manifolds instead of 360. The 340/360 ones I'm speaking of have a flat flange outlet like the early ones. The ones advertised have a coned flange like a 318 A body manifold.
 
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