Spacer plate in front of leaf spring hanger

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imo350

imo350

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Hey there fellow A-body enthusiasts!

So I have an interesting situation with my 1973 Dart Sport 340. When I took the rear end out, I had to grind off the leaf spring hanger plate that mounts to the crossmember and holds the front of the leaf spring. After I ground the welds off and was able to remove the leaf spring and hanger, I found a spacer behind it. There is no sign of damage to the area, so I have to assume that it was put there for a reason. When I re-assembled the rearend, I left the spacer out and then as you can see from the pic below, the wheel is too far forward in the wheel well. All I can assume is that the crossmember that the spring perch bolts to is too far forward in the car and that the factory had to put the spacer in to square up the rear end.

Have any of you ever seen such a thing in an A Body before? Wasn't the car built on a jig to ensure that the crossmember was always in the right spot? I will need to pull the perch back and slide another spacer in to get the rearend square in the car.

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plate2.jpg


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wheelspacing.jpg
 
It is more of a normal thing to find the axles are not square in the chassis and the plate was put there to correct the problem you have found and know the answer to.
 
I don't know that the factory would put such a spacer there. The studs in that hanger are barely long enough to accommodate a spacer.
Those who put on larger wheels and tires discover one side side sits more forward in the well which is normal ( I forget is it right or left and I wont go look in the pouring rain ). Drag racers will add a spacer to alter this offset for a straighter launch.
 
Hey guys, thanks for the feedback. If one side sits more forward in the wheelwell, does that mean the body is not the same from left to right? I would assume if the rearend was not square to the front end that the car would dog track down the road and not drive straight. I did a quick string job and the wheelbase was off from side to side by over 1/2" without the spacer, so I can only assume it was done to square up the rearend in the car.
 
The body is fairly symmetrical. The entire driveline is offset. It has to be for mechanical engineering reasons. Common offset is 7 degrees. Drivelines components, universal joints, differentials, etc.., that are exactly centered will not last. The work load has to be forced to one side or the other no matter how often the load will change sides. It just can't float in the center or it would chatter and eat itself.
Some of the driveline offset designed into vehicles has to do with the crown in the road too. I don't pretend to understand all I know.
 
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It was probabky added to gain space for bigger tires. To center it in the wheel opening
 
The part you pulled has torch-cut slots. I doubt a factory part would be so crudely made. Plus, are they going to take the time on an assembly line to check that after the rear axle is in place? I don't think so.

I would speculate that it was added sometime in your car's previous life. Was it because of an accident? Might be something an alignment shop would do, or by a racer as others have mentioned.
 
I agree that it is odd that the factory would add such a plate, but there is no sign of any damage and the plate was only on the drivers side....
 
Yea, there's no way that was factory.
Like suspected it was probably to square up the rear so the car didn't dog track, or to clear a tire.
 
RedFish said:
The entire driveline is offset. It has to be for mechanical engineering reasons. Common offset is 7 degrees. Drivelines components, universal joints, differentials, etc.., that are exactly centered will not last. The work load has to be forced to one side or the other no matter how often the load will change sides. It just can't float in the center or it would chatter and eat itself.
Some of the driveline offset designed into vehicles has to do with the crown in the road too. I don't pretend to understand all I know.
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huh?
 
TrailBeast said:
Yea, there's no way that was factory.
Like suspected it was probably to square up the rear so the car didn't dog track, or to clear a tire.
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Don't look factory to me, but have any of you guys ever seen how the trans tunnel looks on some 4 speed A bodies? The factory cut some of the auto. humps out to weld in the 4 speed hump, it looked just as bad ! I had my orig rear front hangar bracket left over after installing the 3/4" offset rear spring hangars. I cut the orig. ones up (neatly) and used them for reinforcements. One in front and one in back of the frame mounts, 1/8" Is all that mine was off. Many cars came out way worse, up to a 1/2" off in many areas. And yes, the 3/4" are actually 3/4" , for those of u that want to argue ! Took some doing to get them in there !
 
If it's only on one side it was probably to correct a dogtracking problem. (I didn't notice that in the original post). Here's a thread I found about moving for tire clearance.

Moving Rear
 
famous bob said:
Don't look factory to me, but have any of you guys ever seen how the trans tunnel looks on some 4 speed A bodies? The factory cut some of the auto. humps out to weld in the 4 speed hump, it looked just as bad !
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And I thought somebody hacked that up when the changed from a Inland to a Hurst. My 66 Dart is that way.
 
The trans tunnel in my E body looks like a hack job.
 
As the others have said I doubt the factory would put such a hacked up piece in it. But I have seen all kinds of hacked up things like that installed by shade tree mechanics.

Incidentally the factory 8-3/4 rearend in my 68 Cuda was off about 1/8" but I never noticed it dog walking when I'd follow behind with my wife driving it. What I did notice is one side was closer to the tire than the other. I put a spacer in it and now the back wheels are even side to side and are right in line with the front wheels
 
It was probably hit on one of the front corners at some point and put the unibody into a "diamond". That piece was likely added to bring the rear end back square with an unsquare chassis. I bet if you have the unibody checked on a dedicated frame machine, you will find it is out.
 
RustyRatRod said:
It was probably hit on one of the front corners at some point and put the unibody into a "diamond". That piece was likely added to bring the rear end back square with an unsquare chassis. I bet if you have the unibody checked on a dedicated frame machine, you will find it is out.
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I was at Jim Hales shop back when I first started my 68 fatback restomod. I mentioned to him that I thot someone had hacked in my 4 speed hump. He told me that all the barracudas (I don`t remember about the darts) that got 4 speeds were cut out very sloppy w/ a torch, and the 4 speed humps were tack welded-pop riveted back in, and covered w/ undercoating, and of course carpet up top. He said they weren`t designed for a 4 speed to start with, and that`s the way the factory did it ! I tend to believe him on that , he`s probably built -bought-raced and sold 60-70 of them over the yrs. He has had more than one original factory s/s cars too, also built a bunch over the yrs.
 
RustyRatRod said:
It was probably hit on one of the front corners at some point and put the unibody into a "diamond". That piece was likely added to bring the rear end back square with an unsquare chassis. I bet if you have the unibody checked on a dedicated frame machine, you will find it is out.
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A torch and welding /riveting was the way the factory did it back then. The barracudas weren`t designed for a 4 speed to start with, "don`t know about the darts" Do some research, Jim Hale told me this back when I first started my fish. He should know , he`s probably had, built, bought and raced as many or more than anyone. From stockers to S/SAH cars, and owned at least one of the originals that I know of. jfyi.
 
My Dart has never been wrecked and so it was not a case of putting the car back square from a tweeked chassis. The part that befuddles me is that this plate was only present on the drivers side which goes against the idea that it was done to put bigger tires in the rear. I can only assume that the plate was installed at some point in her life to square up the rear end with the front end. At the moment, she is getting a new paint job and so when I get her back, I will string the sides to see how far out of square she is and then put the smallest plate possible in to correct the difference. I am new to the Mopar and leaf spring game, so I may need to consider moving both sides back a little to get bigger tires in there as currently she is riding on the original 14" Rally rims and I am not planning on keeping those.
 
imo350 said:
My Dart has never been wrecked and so it was not a case of putting the car back square from a tweeked chassis. The part that befuddles me is that this plate was only present on the drivers side which goes against the idea that it was done to put bigger tires in the rear. I can only assume that the plate was installed at some point in her life to square up the rear end with the front end. At the moment, she is getting a new paint job and so when I get her back, I will string the sides to see how far out of square she is and then put the smallest plate possible in to correct the difference. I am new to the Mopar and leaf spring game, so I may need to consider moving both sides back a little to get bigger tires in there as currently she is riding on the original 14" Rally rims and I am not planning on keeping those.
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Keep in mind that if the front end caster isn't adjusted exactly the same on both sides the front to rear wheel center-to-center measurement won't be equal. It may not make a big difference but there'll be some difference. Be careful moving the entire rearend back to gain clearance for bigger tires because you are also pulling the driveshaft out of the trans. when you do that. Sometimes you have plenty of yoke engagement and sometimes not
 
RustyRatRod said:
It was probably hit on one of the front corners at some point and put the unibody into a "diamond". That piece was likely added to bring the rear end back square with an unsquare chassis. I bet if you have the unibody checked on a dedicated frame machine, you will find it is out.
Click to expand...
Common sense, and old school...diagnosis? Agreement ,here...
 
famous bob said:
I was at Jim Hales shop back when I first started my 68 fatback restomod. I mentioned to him that I thot someone had hacked in my 4 speed hump. He told me that all the barracudas (I don`t remember about the darts) that got 4 speeds were cut out very sloppy w/ a torch, and the 4 speed humps were tack welded-pop riveted back in, and covered w/ undercoating, and of course carpet up top. He said they weren`t designed for a 4 speed to start with, and that`s the way the factory did it ! I tend to believe him on that , he`s probably built -bought-raced and sold 60-70 of them over the yrs. He has had more than one original factory s/s cars too, also built a bunch over the yrs.
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They were all designed and built to base model which was bench seat, column shift. The floor pans got drilling, cutting, and welding for any option including bucket seats. And back to the topic... With some measuring you will find the engine is dang near 3 inches right of center, annnnnd this offset fades back to center of the body by the time you reach the differential. Anyway... now grab a framing square and study. Which way would they need to shift the differential to get it closer to square with the rest of the drive line? ( shift the left end forward or right end rearward could work? ).
Every mfgr does these things differently. Like Ford differentials having one axle shorter than the other for example.
So why weren't these Chrysler bodies designed to this offset? Couldn't they shift one or both wheel wells so wheel sits dead center of both? I don't know. I imagine such an offset could echo throughout the build. One rear passenger has more leg room than the other? LOL
We could all go out and measure our a-bodies to verify this offset.
We'll never see one case where the long side was moved forward for any reason.
We often see the short side moved rearward and most cases its for larger that OEM tires.
 
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Abodybomber said:
Common sense, and old school...diagnosis? Agreement ,here...
Click to expand...

He said it was never hit. What he doesn't realize is, someone could have hit a post in a parking lot and done what I am talking about. It doesn't take much.
 
RedFish said:
They were all designed and built to base model which was bench seat, column shift. The floor pans got drilling, cutting, and welding for any option including bucket seats. And back to the topic... With some measuring you will find the engine is dang near 3 inches right of center, annnnnd this offset fades back to center of the body by the time you reach the differential. Anyway... now grab a framing square and study. Which way would they need to shift the differential to get it closer to square with the rest of the drive line? ( shift the left end forward or right end rearward could work? ).
Every mfgr does these things differently. Like Ford differentials having one axle shorter than the other for example.
So why weren't these Chrysler bodies designed to this offset? Couldn't they shift one or both wheel wells so wheel sits dead center of both? I don't know. I imagine such an offset could echo throughout the build. One rear passenger has more leg room than the other? LOL
We could all go out and measure our a-bodies to verify this offset.
We'll never see one case where the long side was moved forward for any reason.
We often see the short side moved rearward and most cases its for larger that OEM tires.
Click to expand...
Never seen one w/ 3" offset engine. Mine is 1 3/8" . --- ??????????
 
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