# tire size



## Droach6498 (Nov 1, 2020)

Anyone know the max width tire that can be installed on the rears. Ive got a 65 goat with 15 x 7 fims. My 67 had 9" rears they said any bigger would rub.


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## bigiron64 (Mar 21, 2017)

I just put 255x60x15 on a 64 with a 7" wheel. Tight but enough room


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## Droach6498 (Nov 1, 2020)

bigiron64 said:


> I just put 255x60x15 on a 64 with a 7" wheel. Tight but enough room


How wide is that I dont know tire sizes


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## Old Man Taylor (May 9, 2011)

I’ve got 275x60-15’s on an 8.5” rim on my 64 GTO.


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## O52 (Jan 27, 2019)

size is in mm. 
255 mm = 10.03"
275 mm = 10.83"


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## BearGFR (Aug 25, 2008)

Droach6498 said:


> Anyone know the max width tire that can be installed on the rears. Ive got a 65 goat with 15 x 7 fims. My 67 had 9" rears they said any bigger would rub.


Here's the thing: "Sloppiness" and inconsistency on the assembly line on the day your car was built, combined with the possibility of prior collision damage sometime during its lifetime means that what fits underneath someone else's car may or may not fit underneath yours. This is especially true when you're wanting to push the limits a little and go taller and/or wider than stock.

The only way to be sure what will fit on your car, is to measure your car.

There are tools that can help you to determine both tire size and wheel backspacing that's needed for them. Something like this, for instance:
Wheel/Tire measuring tool

Bear


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## Droach6498 (Nov 1, 2020)

BearGFR said:


> Here's the thing: "Sloppiness" and inconsistency on the assembly line on the day your car was built, combined with the possibility of prior collision damage sometime during its lifetime means that what fits underneath someone else's car may or may not fit underneath yours. This is especially true when you're wanting to push the limits a little and go taller and/or wider than stock.
> 
> The only way to be sure what will fit on your car, is to measure your car.
> 
> ...


Not very good reviews. $79 to measure a tire size. I know a guy who owns a tire installation and he did a great job on my rears of my 67. Got 9" he said bigger would rub when I hit speed bumps etc. But never thought of guys with hangovers effecting wheel wells. Ive always heard you want to get a car built T W or Th. As Monday they're hung & Friday they cant wait to get to the bar.


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## Droach6498 (Nov 1, 2020)

Droach6498 said:


> How wide is that I dont know tire sizes


Does it rub over speed bumps?


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## BearGFR (Aug 25, 2008)

Droach6498 said:


> Not very good reviews. $79 to measure a tire size. I know a guy who owns a tire installation and he did a great job on my rears of my 67. Got 9" he said bigger would rub when I hit speed bumps etc. But never thought of guys with hangovers effecting wheel wells. Ive always heard you want to get a car built T W or Th. As Monday they're hung & Friday they cant wait to get to the bar.


I have one of those, although a different brand (Percy's Wheel Rite), it worked great when I used it on my '69. Like any other tool, at least part of getting a good result requires the person using it to use it properly.

This one, and mine, require you to bend a stiff piece of wire (supplied with the tool) into the profile shape of the tire. If you don't get that correct, then of course you're not going to get an accurate measurement. I assume they designed it that way to allow modeling any tire size and shape. 

My '69 used (as I recall) G70-14's originally on all 4 wheels. I'm now running 15's all around, P275-15 60 drag radials on the rear and (I forget and I'm too lazy to go look so I'll cop out and say) "smaller" 15's on the front. My rear tires fit and don't rub anywhere, even with full suspension travel - but I can't fit my fingers between the outside sidewall and the quarter panel wheel opening.


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## Mine'sa66 (Oct 30, 2019)

2756015 on 15x8's with about 4.25" backspace is about as wide as you can easily go.


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## Old Man Taylor (May 9, 2011)

Mine'sa66 said:


> 2756015 on 15x8's with about 4.25" backspace is about as wide as you can easily go.


My BS gad to be almost 5” for that combo to work.


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## Old Man Taylor (May 9, 2011)

My wheel is an 8.5”. An 8” wheel should need about 4 3/4” to be centered.


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## BearGFR (Aug 25, 2008)

Old Man Taylor said:


> My BS gad to be almost 5” for that combo to work.


 Yep - mine are on 10" wide wheels and needed 5" of backspace.


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