8 3/4 with 2 perch holes and 1 big 1

[ddpsnake]

not sure witch 1 to use little confused, the 1/2 hole has always been right in the middle,as you can see there is 1 big hole.

 

[RussT Plymouths]

The big hole centers the big rubber ISO mount used on '73 and later cars. I've just welded a spacer in the big hole to center the axle on the spring center bolt. Sorry I don't have one available for a pic.

 

[R/T Boy 67]

 

[moes]

Don, here is some stuff to think about. I found this years ago doing some research on 8 3/4 housings, so I put it in my Mopar folder just incase I needed it in the future. It was on one of the Mopar websites years ago, can't remember. You can thank fellow member Nacho-RT74 for this information .

-axle pedestal are shorter on 73 and later to compensate the extra height added by isolators and clamps
-Guide hole is wider on 73/74 to fit the isolation guide.


-then if you replace spring be sure:
-Stud Guide doesn't have the extra bushing to fit inside isolator. 73/74 springs have a metallic bushing or cup attached directly on guide stud/bolt to fit inside the isolation pad. Extra info: Not sure about this but I have found 5/16" stud/bolts on non isolated and 3/8" guide stud/bolt on isolated springs with the bushing, I'm sure about the last but unsure on the non isolated are 5/16, since my replacement springs were made locally and found with 5/16" guides.
-front hanger bushing hole is the same size than you spring hanger bolt. Later ( 74 for sure, some 73 maybe since I have found both sizes setup on several 73s ) used smaller bolt to fit bigger isolation bushing on same outer diameter.

-and WILL NEED to change the lower plate ( where shock bolts ) to match also between the guide stud/bolt size and hole on plate without isolator

 

[ddpsnake]

no this is not what i want to hear, dam i thought a simple bolt in.

 

[ddpsnake]

The big hole centers the big rubber ISO mount used on '73 and later cars. I've just welded a spacer in the big hole to center the axle on the spring center bolt. Sorry I don't have one available for a pic.

well i like the washer thing, got a hold of a mopar dude that will weld in the wahers in thanks for the tip.

 

[YY1]

looks like you might get a slight rear lift out of the deal

the pin shouldn't be that big of a deal

 

[ddpsnake]

i can get a washer made up, need to know what size the spring locating pin is 1/2 dont know .

 

[ddpsnake]

no more big hole, also call my mopar parts guy who told me the size i wanted case closed.

 

[adk-roadrunner]

no more big hole, also call my mopar parts guy who told me the size i wanted case closed.

View attachment 1005430

what size did the leaf locator hole end up needing to be? I'm getting ready to buy new leaf springs for my 73 roadrunner and I want to get rid of the ISO's. I will definitely weld in some washers and order 72 springs.

 

[ddpsnake]

what size did the leaf locator hole end up needing to be? I'm getting ready to buy new leaf springs for my 73 roadrunner and I want to get rid of the ISO's. I will definitely weld in some washers and order 72 springs.

1/2 inch the shop that did it did a perfect job.

 

[adk-roadrunner]

1/2 inch the shop that did it did a perfect job.

Does your car have a rear sway bar? I'm wondering if I'll have to weld a washer into my sway bar bracket as well if I go to 72 springs. Is there a locator pin in the top and bottom of springs?

 

[ddpsnake]

no sway bar hear,yes there is a pin top and bottom.ya should put the sway bar back for sure.