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Going from 15's to 17's, question about backspacing for the rears.

  • Thread starter Thread starter torino420
  • Start date Start date Jun 7, 2007
T

torino420

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Jun 29, 2006
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Jun 7, 2007
#1
  • Jun 7, 2007
  • #1
My car has 15x8's with 4.5" backspacing with 295 50's. The wheels are damn near centered in the wheelwell.
I know theres that cool tool for determining proper backspacing but I'm looking for opinions since the 8's fit perfectly.
When I measure from both the inner and outer edge of the wheel i have about 1.5" minimum clearance. With that in mind what backspacing do you think i need to run a 17x9.5" wheel.
I have to custom order the rears so they need to be right.
I have an idea what backspacing i need but want some other opinions.


thanks
 

dodgestang

Active Member
Dec 15, 2003
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Cecil County, MD
Jun 7, 2007
#2
  • Jun 7, 2007
  • #2
5.25 will put the center of the 17x9.5 in the same place as the center of the 15x8 4.5bs
 
T

thekid760

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Jun 8, 2007
#3
  • Jun 8, 2007
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will that fit on the stock rear of a 65 mustang GT? what about tire size?
 

Pakrat

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Aug 6, 2000
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Currently: NH Originally: Rhode Island (and all po
Jun 8, 2007
#4
  • Jun 8, 2007
  • #4
What size tire are you planning on? I just custom ordered some 17x9.5 rims a while back for the rear of my 69' and I plan to run a 275/40/17 on them so I went with 5.5" BS.
 
T

torino420

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Jun 29, 2006
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Jun 8, 2007
#5
  • Jun 8, 2007
  • #5
285 40's...
 

dodgestang

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Dec 15, 2003
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Jun 8, 2007
#6
  • Jun 8, 2007
  • #6
thekid760 said:
will that fit on the stock rear of a 65 mustang GT? what about tire size?
Click to expand...

No. Once you mount a tire it will be too wide for the stock wheel wells IMO.
 

65fastbackresto

Active Member
Apr 13, 2007
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Jun 8, 2007
#7
  • Jun 8, 2007
  • #7
I can tell ya something NOT TO DO

Some bozo stuck 17 by 9.5 on my 65, 4 1/2 inch backspacing, and they rub when I hit a bump with 3 or more people in the car. I do think 5 inch backspacing would fix it though.
 

Pakrat

Founding Member
Aug 6, 2000
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Currently: NH Originally: Rhode Island (and all po
Jun 10, 2007
#8
  • Jun 10, 2007
  • #8
Geez, they must stick out way past the fender too.
 

65fastbackresto

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Apr 13, 2007
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Jun 10, 2007
#9
  • Jun 10, 2007
  • #9
No they dont stick out at all

Its all tucked under the fender, but a little to close to the upper inside well. It just BARELY rubs when I hit a bump. With a shorter tire, it would prob fix it, but a shorter tire would never fix the front.
 

Pakrat

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Aug 6, 2000
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Currently: NH Originally: Rhode Island (and all po
Jun 11, 2007
#10
  • Jun 11, 2007
  • #10
Hunh, I'm having a hard time visualizing how it could be tucked at 4.5 BS when that's what you would use on an 8" rim?!??!! That extra 1.5" has to go somewhere.
 
R

ron67fb

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Aug 3, 2001
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SF Bay area, CA
Jun 11, 2007
#11
  • Jun 11, 2007
  • #11
I have yet to see pics of your car, 65fastbackresto. So far I've gathered you have 10 and 9.5 inch wheels, 4.5-inch backspacing, 215/45-17s... ??
 
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