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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Rims don't fit!

  • Thread starter Thread starter wyant50
  • Start date Start date Jan 4, 2008
W

wyant50

New Member
Jan 2, 2008
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1
Jan 4, 2008
#1
  • Jan 4, 2008
  • #1
I guess it could of been the way backspacing and off set was explained to me which may of gotten me in this position but none the less I have a problem.

I have a 66 coup if it matters.

I picked up a set of weld prostar wheels and tires today and was excited about putting them on. From what I understand the rims are 15x8 with a 5.5" backspacing. I do not know what the offset is. When trying to mount the tires I ran into a problem.. The tire was touching the leaf spring and I was unable to get the rim on any further than just hanging off the studs the lug nut screws onto. (sorry I can't recall the name)

After doing some research I think I see what the problem is..

My rim has a positive offset and has too large of a back spacing. This is causing there to be more tire further 'in' so I am unable to push the rim fully onto the studs.

To correct this problem I will need a rim that has either a negative or zero offset and a smaller backspacing.

The tires that are on the rims are 275/50/15. What other tire combinations will give me a tread with that is not so wide and possibly not so tall?

I hope this all makes sense and thanks for any input someone gives me!
 

deltascrew

Member
Oct 11, 2007
27
2
6
Mississippi
Jan 4, 2008
#2
  • Jan 4, 2008
  • #2
They might work if you use 1"spacers, that would make 4.5" backspace. I am running 245/45/17 with 4.5 backspacing, and had to roll the fenders. you will probably have to go with smaller tires
 

Capt Dan

New Member
Mar 31, 2005
237
0
0
College Station, Texas
Jan 4, 2008
#3
  • Jan 4, 2008
  • #3




On a 8" rim, 0 offset = 4" backspace
your 5.5" backspace = 1.5" offset (I forget which way is + or -)

You should be running 4"- 4.5" BS acording to the Dodgestang chart

http://www.dodgestang.com/Tire%20Fitment%20Guide%2065-6.pdf
 

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iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jan 4, 2008
#4
  • Jan 4, 2008
  • #4
 

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F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Jan 5, 2008
#5
  • Jan 5, 2008
  • #5
Just buy a good quality bolt-on spacer.
 
W

wyant50

New Member
Jan 2, 2008
21
0
1
Jan 5, 2008
#6
  • Jan 5, 2008
  • #6
Got some good news and bad news.. The parts guy at the shop I get my car worked on had his wheels stolen and they are the exact same as the ones I have. So he is buying mine and adding money since I drove 100miles round trip to get them.

Now I'll just get some ones that will fit the right way!
 

SnwMnkys

Founding Member
Apr 21, 2002
381
0
17
Orem, Utah
Nov 5, 2009
#7
  • Nov 5, 2009
  • #7
On a 8" rim, 0 offset = 4" backspace
your 5.5" backspace = 1.5" offset (I forget which way is + or -)

You should be running 4"- 4.5" BS acording to the Dodgestang chart
Click to expand...

This is and isnt entirely true. Backspacing is measured from flange the hub sits sits on to back side of wheel. A 8" advertised wide wheel isnt really 8" wide, its 9" from lip to lip. So an 8" advertised rim with 0 offset would have 4.5" backspacing.
 
2

2+2GT

10 Year Member
Apr 25, 2009
3,333
10
79
Southeastern Pennsylvania
Nov 6, 2009
#8
  • Nov 6, 2009
  • #8
wyant50 said:
Got some good news and bad news.. The parts guy at the shop I get my car worked on had his wheels stolen and they are the exact same as the ones I have. So he is buying mine and adding money since I drove 100miles round trip to get them.

Now I'll just get some ones that will fit the right way!
Click to expand...

Make sure they comply with this guide:

 
P

pyroman

Founding Member
Jul 28, 2002
480
3
18
Ennis, Texas
Nov 6, 2009
#9
  • Nov 6, 2009
  • #9
I have a question to add. I was looking to pick up some 17x9s bullit wheels that fit 99-04 Mustangs. As I understand they will fit will a 1" spacer on my 67. Is that right?
 
G

Grabber70Mach

Member
Jul 6, 2003
305
0
17
Indian Head, MD
Nov 7, 2009
#10
  • Nov 7, 2009
  • #10
pyroman said:
I have a question to add. I was looking to pick up some 17x9s bullit wheels that fit 99-04 Mustangs. As I understand they will fit will a 1" spacer on my 67. Is that right?
Click to expand...

These will work for you.

Wheel Conversion Kits — Vintage Venom - Vintage Mustang Disc Brake Kits
 
6

67efivert

Member
Jan 26, 2003
348
0
16
lincolnton nc
Nov 10, 2009
#11
  • Nov 10, 2009
  • #11
to pyroman u would ba alot better off with 17x8 the 9 is too much for the front ive got a custom setup with a .700 spacer with 8" cobra wheels and with the lowered front i have i still sometimes get some fender rub
 
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