My 75 Finally Gets The Attention It Deserves(This Could Take a While)

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According to my parts manual the correct pn is 3870059, but I’ve had no luck even finding a picture of a manifold with that number, let alone the actual manifold. I want to get this right so I guess I’ll keep looking for it.
 
I found the ad that the last picture above is from, but the part number, 2843953, doesn’t show up in my manual anywhere. If the correct manifold looks the same then the part number isn’t all that important to me. I’ll buy the darn thing if it looks right.
 
skewered. Pic of the other side, but it looks just like the one I pulled off a 74 teener I took from a 74 dart parts car.
 
Searched an ancient sale thread I had. Heres pix of the pair I pulled from a granny 74 318 dart. Car was a rough moredoor I cut apart but unmodified. No closeup shots so no part numbers but they look just like this.

20190818_105635.jpg
 
Thanks for posting that. At least I know what I’m looking for now.
 
Interesting.

When I upgraded my 318 with a 4bbl, although my Scamp already had a dual exhaust, it was small diameter and quite old (installed in the early ‘90’s), so I replaced it with a 2.5” exhaust with the 71+ 340/360 exhaust manifolds. The 318 manifolds I had removed looked exactly like the pair you recent found Tanker (passenger side one had the ribs on it).
 
Interesting.

When I upgraded my 318 with a 4bbl, although my Scamp already had a dual exhaust, it was small diameter and quite old (installed in the early ‘90’s), so I replaced it with a 2.5” exhaust with the 71+ 340/360 exhaust manifolds. The 318 manifolds I had removed looked exactly like the pair you recent found Tanker (passenger side one had the ribs on it).
That certainly throws a new wrinkle into things. Thanks for sharing that. It looks like I have some additional research to do before I install a right hand exhaust manifold.
 
That certainly throws a new wrinkle into things. Thanks for sharing that. It looks like I have some additional research to do before I install a right hand exhaust manifold.

Here’s a picture of the manifolds on my ‘75 318 before I replaced them with 340 manifolds. I tossed the 318 manifolds last year so can’t pull a part number off them.

340 Manifolds on 318

The car has been in my family since new so I have all the service records, including when the engine was replaced when a wrist pin failed even though the engine only had 25k miles on it. Since it was before I had my licence, I can’t definitively say that ribbed manifold is the original one. However, the 2bbl original carb, alternator, power steering pump and all other accessories from the original 1975 engine were re-installed on the new engine. I would find it odd that the shop would re-install the other original accessories on the new block except for the passengers side exhaust manifold?
 
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Looking at another engine bay of a ‘75 318 Scamp, which is low mileage, it also has the ribbed passenger side exhaust manifold. This is from @Woody’sScamp garage profile.

486681F6-A0F4-492A-90CF-2F2B95839297.jpeg


Tanker, unless another member has definitive proof that a ‘75 manifold should be the same as a ‘74 318 (not ribbed) I think you’ve got the right manifold.
 
I finally managed to track down what I believe to be the correct factory exhaust manifolds for a 75 on eBay. They'll need some cleaning up prior to use, but that's not a problem. At some point in the future I may very well put headers back on the car, but for now I'll have a shop fabricate the pipes to connect these to the dual exhausts the car has. That being said, I'll never discard the factory manifolds again the way I did when I put the headers on at 18. I like the idea of being able to return to a stock configuration if I want to.
View attachment 1715659510
Those look like the same ones I have on my 75 318s. I have a very original 75 duster and a 75 swinger. Starting in 75 they are supposed to look like 360 manifolds like that. 74 and 75 had different manifolds on a 318

20201225_155535.jpg
 
Case closed! 75 318’s had ribbed passenger side exhaust manifolds.
 
Thanks to all of you that helped sort this out. I guess I’ll go ahead and use the manifold I just purchased for the passenger side.
 
The ones on the left are from a 74 duster and the ones on the right are from my 75 swinger (75 date coded)

Resized_20200425_185214.jpeg
 
I think the 75 and up manifolds are less restrictive because you can see the ports are bigger. I even thought they were 360 manifolds at first but the 75 duster has the same ones. I think the later ones are better but more overlooked because of the prejudice against later 74 and up stuff
 
I think the 75 and up manifolds are less restrictive because you can see the ports are bigger. I even thought they were 360 manifolds at first but the 75 duster has the same ones. I think the later ones are better but more overlooked because of the prejudice against later 74 and up stuff
Looks good to me
 
I have a couple of quick questions. First, the drivers side exhaust manifold heat shroud has two small holes in the upper surface that would have been where the inner shield attached. Did all manifolds with this configuration use that inner shield? I don't have one and I'm wondering if it's yet another piece I need to track down, or can I braze them shut and be done with it? While we're at it, what was its purpose? It doesn't look like it would help direct warm air to the air cleaner inlet, so was it there to protect plug wires?

Second question, after sitting for thirty five years my three speed transmission is at a shop getting a look over. I also have a four speed back in L.A. that I bought years ago and never got around to installing. Is it an easy task to switch from a three to a four speed, or a major undertaking? I'd imagine there are some additional parts I'd have to track down, but I've never look into it enough to know what I'm up against.
 
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3 to 4 speed swap is going to be very easy. Should be the same bellhousing and everything bolts in the same place.

Only difference is going to be the slip yoke. The 3 speed uses the smaller 904 yoke and the 4 speed uses the bigger 727 yoke.

The 3 and 4 speed are the same length so your driveshaft will work by swapping the slip yolk.
This is assuming you have an A body 4 speed
 
3 to 4 speed swap is going to be very easy. Should be the same bellhousing and everything bolts in the same place.

Only difference is going to be the slip yoke. The 3 speed uses the smaller 904 yoke and the 4 speed uses the bigger 727 yoke.

The 3 and 4 speed are the same length so your driveshaft will work by swapping the slip yolk.
This is assuming you have an A body 4 speed
3 to 4 speed swap is going to be very easy. Should be the same bellhousing and everything bolts in the same place.

Only difference is going to be the slip yoke. The 3 speed uses the smaller 904 yoke and the 4 speed uses the bigger 727 yoke.

The 3 and 4 speed are the same length so your driveshaft will work by swapping the slip yolk.
This is assuming you have an A body 4 speed
Thanks Princess. It’s been nearly forty years since I bought that four speed and it’s tucked away where I haven’t even seen it in about half that time. I’ll see if I can get one of my nephews to send me a picture of it so it can be identified. I seem to recall that it came out of a Duster that the guy had put an automatic in, but I don’t really trust my memory from that far back.
 
Those A230 three speeds are well overlooked.

Don't toss it like it's "just an old transmission"

Several different 3 speed types are in existence but the A 230 is one of the best ones, they are tough and build by the same people who built the NP833 four speeds we all know and love.

I try to pick them up when I see them because it's good hardware and more fun than a 904.
 
Progress continues, though much more slowly than I'd like. I just spent over a thousand dollars on needed parts and I'm nowhere near finished spending on this project. Just for grins I thought I'd post this photo of one of my windshield wipers(the other is about the same). This is what happens when years worth of wet decaying leaves are left on top of a parked car. I've recently acquired a nice used set with the correct locking feature to replace this, but I'll still need to replace the wiper pivots. They suffered a fair amount of corrosion as well.
IMG_4951.jpg
 
Was reading theu your thread again. Pretty cool that your parents didnt junk it or sell it on you. I hear too many horror stories of people going into the armed forces, and for some reason their folks sell their stuff. I honestly dont understand why people do that. BTW what brand of wagon is that in the backround in your first pic? Is it a chevelle wagon?
 
Was reading theu your thread again. Pretty cool that your parents didnt junk it or sell it on you. I hear too many horror stories of people going into the armed forces, and for some reason their folks sell their stuff. I honestly dont understand why people do that. BTW what brand of wagon is that in the backround in your first pic? Is it a chevelle wagon?
That’s a 1971 Plymouth Satellite wagon with a slant six. And yes, I’m lucky to still have the car after all these years.
 
I know I'm late seeing this, but here is a closeup of the passenger manifold I took off my '75 Scamp. My car was an early year build, late August '74. I also included a pic of the 360 manifold that eventually I will be using. Your car is looking good, I am starting to following your build.
Passenger (7).JPG
PASSENGER SIDE DOWNPIPE (1).jpg
 
My last post was in April of 2021. Pathetic, isn't it? Not much happened for quite a while as life got in the way big time, but I've started back up again trying to get her ready to go in for body work and paint. Unfortunately the car has at least five previous layers of paint and I don't want to add another layer to it, so I'm in the process of sanding it down to a mixture of the factory primer and bare metal. I'm also removing everything from the outside that doesn't get painted, so all trim, bumpers, door handles, marker lights, etc. The last time I did this to this car was in the mid to late 80's when I was in my twenties, so a while ago.
1975 Plymouth Duster w Front Bumper Removed.jpg

While taking the bumpers off one of the mounting bolts for the rear bumper snapped in half. You can see it in the image below along with another one that in spite of the rust is still in decent shape. I'm going to need to find a replacement for that. Does anyone know if these are available new, or will I need to find a used one?
!975 plymouth Duster Bumper Mounting Bolts.jpg

I also discovered that one of the AMD patch panels for the lower rear quarters is incorrect for my year and will need to be replaced, but I no longer see these listed on their web site. I may have to get the entire quarter and get what I need out of it.
1975 patch panels.jpg
 
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