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Update on post #18! Need help asap please! 275/60r15 on 8.5" rim with 3.75" backspace 65 Satellite?

Nismobishi

Nismobishi

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Hello all,
I'm getting new tires and I want to fit 275/60r15 but I see most people use 4.5" backspace for these. My torq thrust rims are 3.75" backspace. I have 235/60r15 right now and my measurement from the sidewall to the fender lip is about 5/8" (about a finger size gap. From the sidewall to the leaf spring is huge. If I am doing my math right then a 275 is about an inch and a half wider than a 235, therfore adding about 3/4" to each side of the tire. I will be rubbing unless I trim the outer fender lip right???

20230806_134437.jpg
 
I agree with the above. 275/60/15 with a 4 1/4'' backspace worked fine on my 65.
The 3 3/4'' Torque thrusts on the 65 I had to run 255/70/15.
Now the same rim with 4 1/4 '' and 275's on my 63 rubbed only on the passenger side.
So what I'm getting at is no 2 Mopars are the same. You may be fine, but then again....

IMG_2738.jpg
 
Darter6 said:
I agree with the above. 275/60/15 with a 4 1/4'' backspace worked fine on my 65.
The 3 3/4'' Torque thrusts on the 65 I had to run 255/70/15.
Now the same rim with 4 1/4 '' and 275's on my 63 rubbed only on the passenger side.
So what I'm getting at is no 2 Mopars are the same. You may be fine, but then again....

View attachment 1505887
Click to expand...

Is that the 255/70 with 3.75 BS in this picture? What are you running on the front, do you have a picture of the whole car?
 
I seriously doubt you will be able to run 275s, and I'm not sure about 255s.
I have a couple pair of 15x8 1/2 with 3 3/4 backspace, and 225/235 is all that will fit on my 62, and a 62 has a lot more room than a 66/67 b-body.
You have zeroed in on the problem with the one piece tt's. Not enough backspace. They look great, and work great on cars with full open wheelwells.
 
Yes. Front was 225/70/15 Sold the car a few years ago.
Nismobishi said:
Is that the 255/70 with 3.75 BS in this picture? What are you running on the front, do you have a picture of the whole car?
Click to expand...

IMG_2737.jpg


IMG_2734.jpg


IMG_2735.jpg
 
Nismobishi said:
Man I love the look of that! I might copy those tire sizes! I'm wondering if you think the 255/70 will fit being that my rims are 8.5 3.75BS and yours were 7 with 3.75BS. I think they will... hopefully.
Click to expand...
You have 5/8 or so to the fender. A 255 is almost an inch wider than a 235,so a half inch more in each direction. Leaves you 1/8 of an inch. Think that will work?
Sorry.
Edit:your 8 with 3.75 backspace moves everything an inch closer to the fender than his 15x7 with 3.75 bs. The exact problem with not-enough bs.
 
I think you will be ok with 70's on a 8.5 rim.
No 2 tire manufactures make sizes exactly the same, tho numerically they are the same.
I have run 75 series on a 8'' rim without a problem or looking stupid.
 
I just ordered Cooper Cobra 225/70r15 and 255/60r15. I really wanted to go 255/70 on the back but my rims won't allow for it. I'll post pics soon. Thanks to everyone for the help!
 
A 255/70 or75 will go on any rim that will take a 255/60. Widths are (supposedly) all the same, 255mm section. The difference is height.
Unless height is the problem regarding your fender interference, a 255/70 will work if a 255/60 will.
(I have the same problem you do. I've got a 255/70 street tire on my steelies, cause of too little backspace. On the right rims, I have the equivalent of a 295/55x15, a 10.5x28 slick)
 
33 IMP said:
A 255/70 or75 will go on any rim that will take a 255/60. Widths are (supposedly) all the same, 255mm section. The difference is height.
Unless height is the problem regarding your fender interference, a 255/70 will work if a 255/60 will.
(I have the same problem you do. I've got a 255/70 street tire on my steelies, cause of too little backspace. On the right rims, I have the equivalent of a 295/55x15, a 10.5x28 slick)
Click to expand...

Yea, unfortunately after looking in my fenderwell, by the time a 70 series comes out about a half inch and then goes up another inch and a half it will hit the fender curve. Therefore I went with the 60 series cause it will only go up a half inch instead of an inch and a half.
 
Cojohnso1 said:
I would have sellers remorse big time.
Click to expand...
Owned it 18 years. Multiple drive line changes. Even drag raced for awhile. But in the last 5 years only drove it 600 miles.
It needed someone that would use it and enjoy it more. I like building them more than owning them.
 
Ok, here it is! 225/70r15 front and 255/60r15 rear. The stance needs to be changed.

What does FBBO think? Lower the front or lift the back. Or both???

I'm thinking pop the rear up about an inch and drop the front about a half inch.

20230810_132151.jpg


20230810_132344.jpg


20230810_132408.jpg


20230810_132201.jpg
 
I agree. I'd lift the rear to get a bit more clearance, and drop the front. Like a little rake, and I LIKE your car and wheel combo!
 
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