YES 5.9 Magnum manifolds work in early A bodies. Here is exactly how!

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Crossing my fingers the manifolds I pulled off a ram van with 2-1/8" openings fit. Also got the pass side off of a JGC, also 2-1/8.
 
Crossing my fingers the manifolds I pulled off a ram van with 2-1/8" openings fit. Also got the pass side off of a JGC, also 2-1/8.
Yea I'm really hoping mine will work out also. I'm concerned about the steering rubbing.
 
Crossing my fingers the manifolds I pulled off a ram van with 2-1/8" openings fit. Also got the pass side off of a JGC, also 2-1/8.
The passenger's side manifold off of a van will usually fit but the design of the manifold will cause it to exit near the fire wall introducing a little heat into the floorboard. But they will work. I never tried the driver's side manifold off of a van because vans have tons of room on the driver's side compared to an A body so they weren't worried about cramped spaces.
 
Yea I'm really hoping mine will work out also. I'm concerned about the steering rubbing.
The JGC driver's manifold will not work on an A body if that's what you have. The JGC had the starter on the passenger's side which made a lot of space on the driver's side. I tried to install the 2 1/4 inch JGC manifold on my '69 Barracuda. There's no way it will fit unless you're able to drive your A body without the starter!! OR....install the JGC motor in your A body so that you have the starter on the passenger's side!!
 
The JGC driver's manifold will not work on an A body if that's what you have. The JGC had the starter on the passenger's side which made a lot of space on the driver's side. I tried to install the 2 1/4 inch JGC manifold on my '69 Barracuda. There's no way it will fit unless you're able to drive your A body without the starter!! OR....install the JGC motor in your A body so that you have the starter on the passenger's side!!
No mine are not JGC they are standard small magnums off a 01 ram I believe
 
So I am doing this same 5.9 magnum swap into a 65 valiant with power steering. Am leaning towards using the magnum manifolds. I have a manual box ready to go and I have the steering shaft out of the manual car as well. Should I just go with the manual shaft or use the power steering shaft with previously mentioned coupler? I figured the manual shaft would be the way to go?
 
So I am doing this same 5.9 magnum swap into a 65 valiant with power steering. Am leaning towards using the magnum manifolds. I have a manual box ready to go and I have the steering shaft out of the manual car as well. Should I just go with the manual shaft or use the power steering shaft with previously mentioned coupler? I figured the manual shaft would be the way to go?
*Edit* this info is for 67+ only. Missed that you had a 65.

There’s really no difference between the manual and power shafts, other than how far they’re collapsed from the factory. All you have to do to get a “power” shaft to work with a manual box is pull the shaft out farther. It might take a little persuading as there are a few small plastic globs melted to the shaft to hold it in its factory location. To get a “manual” shaft to fit a power box, just knock the shaft back into the column a few inches. But if you completely take a manual shaft and a power shaft apart, the inner shafts are both the same length. Always blows my mind that people dish out the money for that adapter
 
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Nice write up! Just a little food for thought. Those Sweet steering joints are racing joints and are not near as beefy as the Borgeson or Flaming River joints. The first time I saw one of those Sweet U joints, a friend was into stock cars and was using them. I made a comment at the time how thin and spindly they looked--Plus the fact that he bought them from Speedway Motors here in Lincoln NE. Just make sure you do compare shopping with these joints. Be safe!
 
Just adding to the above post. I just looked at the Sweet website and it states that their steering universal joints can be used on virtually any OFF-ROAD steering application. I would say NOT for street use. And the one listed above-a Chinese knock-off for sure NOT. Remember, your life and others depend on this critical u joint! Borgeson and Flaming River are both manufactured in the US.
 
There’s really no difference between the manual and power shafts, other than how far they’re collapsed from the factory. All you have to do to get a “power” shaft to work with a manual box is pull the shaft out farther. It might take a little persuading as there are a few small plastic globs melted to the shaft to hold it in its factory location. To get a “manual” shaft to fit a power box, just knock the shaft back into the column a few inches. But if you completely take a manual shaft and a power shaft apart, the inner shafts are both the same length. Always blows my mind that people dish out the money for that adapter
Hold up.....you sure about that? Were talking a 65, not a collapsible shaft. There are no plastic globs in there and the shafts are physically longer within the columns in the manuals to compensate for the shorter boxes. The steering wheel position does not change between manual or PS so it cant be a shaft adjustment. Here is a 65 power shaft I extended to a manual, note distance between dimples of the old cut shaft and the manual extension I hacked from a yard shaft. Its about 2.5"
shaft2.JPG
 
Hold up.....you sure about that? Were talking a 65, not a collapsible shaft. There are no plastic globs in there and the shafts are physically longer within the columns in the manuals to compensate for the shorter boxes. The steering wheel position does not change between manual or PS so it cant be a shaft adjustment. Here is a 65 power shaft I extended to a manual, note distance between dimples of the old cut shaft and the manual extension I hacked from a yard shaft. Its about 2.5"
View attachment 1715615121
Oh. You’re probably right, there. I missed the fact that it’s a 65. I’ve only ever messed with 67+ stuff myself.
 
Wouldn't fit on the driver side of my 67 because my Z bar in in the way. Might be OK on an automatic.
Did it clear the steering shaft? I have an auto and did a floor conversion so I striped all the linkages from the column im a little concerned about the clearance between the manifold and the steering shaft. It looks to me like the op has his offset the bearing is in front of the bore. I don't want to do that. But I'm not sure if the steering is in the same place on the later a body's compared to the early ones.
 
Did it clear the steering shaft? I have an auto and did a floor conversion so I striped all the linkages from the column im a little concerned about the clearance between the manifold and the steering shaft. It looks to me like the op has his offset the bearing is in front of the bore. I don't want to do that. But I'm not sure if the steering is in the same place on the later a body's compared to the early ones.
Yes the right side looked clear sailing also.
 
Don't see the big advantage there's probably a 5-7 hp difference, there's a 4 hp difference between 318 to 340 manifolds don't see 273 being much worse than 318 and magnum being that much better than 340. There is another shoot out which I can't find now that the best combo is one side 340 and the other magnum, forget which one's though.

Some Headers are arguably worth it on a 300 ish hp engine.

Installing Exhaust Headers Into 300hp Crate Engine - Mopar Muscle Magazine
 
Don't see the big advantage there's probably a 5-7 hp difference, there's a 4 hp difference between 318 to 340 manifolds don't see 273 being much worse than 318 and magnum being that much better than 340. There is another shoot out which I can't find now that the best combo is one side 340 and the other magnum, forget which one's though.

Some Headers are arguably worth it on a 300 ish hp engine.

Installing Exhaust Headers Into 300hp Crate Engine - Mopar Muscle Magazine
The advantage for me is I happen to have a set of magnum manifolds and I don't have a set of abody manifolds. I have a set if headers but I am not sure if I want to use them or not. I like the look manifolds and they are more convenient than Headers
 
The 340/Magnum combo is the magnum driver and 340 Bi-Y passenger. Trouble is the 340 passenger Bi-Y is $200 alone so the $50/set Magnums are a steal. Not even worth the hassle tracking down that piece.
 
The 340/Magnum combo is the magnum driver and 340 Bi-Y passenger. Trouble is the 340 passenger Bi-Y is $200 alone so the $50/set Magnums are a steal. Not even worth the hassle tracking down that piece.
I got my magnum manifolds on Facebook market place for 35 bucks and they where already cleaned and painted. If they don't fit in my dart for some reason I will use them for something I have plenty of small block mopar engines I could put them on for 35 bucks I will use them eventually lol

20200919_144241.jpg
 
Don't see the big advantage there's probably a 5-7 hp difference, there's a 4 hp difference between 318 to 340 manifolds don't see 273 being much worse than 318 and magnum being that much better than 340. There is another shoot out which I can't find now that the best combo is one side 340 and the other magnum, forget which one's though.

Some Headers are arguably worth it on a 300 ish hp engine.

Installing Exhaust Headers Into 300hp Crate Engine - Mopar Muscle Magazine
Yes seems like a lot for not much gain? Years ago I acid ported some 273 manifolds
with because I had them on Early A w power steering with a 3 inch single exhaust system similar to Formula S. Seems to work very good.
 
Overall thing to take away, is these tests were done on an otherwise "one stock" style engine with no real performance adders. For our engine though, out of a 98 durango, the article is probably spot on. Not much to gain so this is food for thought. Might just stick with the 273 manifolds for now.
 
Agree alot on most posts on this.
However, with magnum 5.2 with la motor.mounts (rubber,and important)

Can't compromise clearance in 4 spd for obvious reasons. The whole idea I rid the 273 manifolds should also be obvious.

I am now modifying 340 driverside manifold from 72 and up duster believe to fit 5.2 magnum 4spd ,future power steering in my situation if nothing else.with large torsion bars with at least 2" down pipe unlike the 15/8" it came with,again I believe.
Anyone else can chime in great...
If I'm satisfied with mod I will send pics and details
1965 Dart/vert.....

Thanks
Dave
 
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