18x8.5 +30 offset all around on 72 duster?

-
72smallairparticler

72smallairparticler

Well-Known Member
Joined
Oct 7, 2022
Messages
252
Reaction score
227
Location
campbell CA
18x8.5 wheels
+30 offset (~6" backspace)

if I run that size on all 4 corners with a spacer on the rear maybe it'll work?
(stock rear with 7 1/4 axle, fronts with 13" cobra brakes)

@72bluNblu thoughts?
 
You can also run a 68-70 B-body rear end and move the spring saddles in 1/2" on both sides. That would also get you a rear 1.5" wider on both sides. Much cheaper that large bolt A-body rears.

Would be good idea since you are moving spring saddles at that point, to move the spring 1/2" more inwards with a bolt on A-Body Offset Spring Hanger/Shackle Kit: Mopar A-Body 1/2" Spring Relocation Kit Offset Hangers & Shackles

Rear end widths, drum-to-drum:

A BODY
'66-'72= 57 1/8"

B BODY
'62-'63= 58 1/2" (And '64 Max Wedge)
'64 = 60 7/8" (Exc.Max Wedge)
'65-'67= 59 1/2"
'68-'70= 60 1/8"
'71-'74= 63"
'71-'73 wagon= 64 3/8"


Spring perch widths (center-to-center)

A BODY
'66-73= 43"

B BODY
'62-'70= 44"
'71-'74= 47.3"

C BODY
'65-'73= 46"

E BODY
'70-'74= 46"
 
autoxcuda said:
You can also run a 68-70 B-body rear end and move the spring saddles in 1/2" on both sides. That would also get you a rear 1.5" wider on both sides. Much cheaper that large bolt A-body rears.

Would be good idea since you are moving spring saddles at that point, to move the spring 1/2" more inwards with a bolt on A-Body Offset Spring Hanger/Shackle Kit: Mopar A-Body 1/2" Spring Relocation Kit Offset Hangers & Shackles

Rear end widths, drum-to-drum:

A BODY
'66-'72= 57 1/8"

B BODY
'62-'63= 58 1/2" (And '64 Max Wedge)
'64 = 60 7/8" (Exc.Max Wedge)
'65-'67= 59 1/2"
'68-'70= 60 1/8"
'71-'74= 63"
'71-'73 wagon= 64 3/8"


Spring perch widths (center-to-center)

A BODY
'66-73= 43"

B BODY
'62-'70= 44"
'71-'74= 47.3"

C BODY
'65-'73= 46"

E BODY
'70-'74= 46"
Click to expand...
I would probably recommend that route too but I already got BBP rear axles installed on my 7.25 rear end. It’s also a slant 6 car and I’m keeping it that way.
 
72smallairparticler said:
I would probably recommend that route too but I already got BBP rear axles installed on my 7.25 rear end. It’s also a slant 6 car and I’m keeping it that way.
Click to expand...

You shouldn't have any issues if you want to run the spacers. 1.5" seems like a lot but compared to the 4x4 crowd its not all that big, and they tend to run way bigger tires and higher wheel mass. Thinner spacers are actually more fragile as they've got less material to hold the second set of studs. Biggest thing is just to make sure that you check the torque on BOTH sets of lug nuts, somewhat frequently at first especially.

I run a '68-70 B body 8 3/4 in my Duster, it's not a bad way to go as they're a bit cheaper than the A-body version but it really depends on the wheels you want. I have 18x10's with a +38 offset (7" backspace) on mine with 295's, but I also have the springs offset a 1/2". With wheels less than 9" wide it's pretty easy to find the higher offsets for the wider 8 3/4. Once you get to 10" or more it seems the offsets all drop down, I've considered putting an A-body width 8 3/4 back in my Duster so I can run 18x11's with a +15 ish offset as that's a more popular offset for that width.
 
It sounds like you are trying to optimize your tire set up. Keep in mind that the slant six is perfectly capable of wrecking that 7.25 inch rear. More traction may only expedite that process.

Whatever you do, plan on being kind to that equipment. That’s all.
 
If you keep the 7.25 rear..try to source a sure-grip unit for it...they are hard to find but make the 7.25 much stronger
 
You must log in or register to reply here.
-

Back
Top