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Discussion Starter #1
Hi, I am picking up my car next tuesday (69judge clone) anyway, I was wondering abut tires. If they are crap and need to be replaced, I was wondering what other widths would work with the rally wheels. Something with a little more meat, but no rubbing issues works. I did it on a tire calculator, and 225 70 14 is pretty mch bang on diameter as the factory 215 75 14. Would 235 even fit on the rear or is 225 the biggest with no issues
 

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I have 14" Rally wheels as well. From my searching last fall the largest (widest) I could go was 225 on my 14" rims. (would liked to have gone a little wider)

You may have to go to a larger rim.
 

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Discussion Starter #3
After doing the wheel calculator there isn't a 235 made that is near equivelant to the diameter of the 215/75/14 tire. The 225 70 14 looks to be the safest bet for fitment and diameter. not much difference of width really to give any better traction though
 

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Here are the calculations on a 235mm tire with both 60 and 70 aspect ratios;


Tire width,

235 X .03937 = 9.25"

Aspect Ratio 60 series

9.25 X .60 = 5.55" sidewall height

Tire height

5.55 X 2 + 14" wheel size = 25.1"

Aspect Ratio 70 series

9.25 X .70 = 6.47" sidewall height

Tire height

6.47 X 2 + 14" wheel size = 26.9"

A 9.25" wide tire will work on our cars as long as the backspace is correct, the 60 series at 25.1" tall should not have rubbing issues and the 70 series may be too tall at 26.9"

The wheel width needs to be 6.5" to 8.5" wide, BFGoodrich has the TA radial in 235/60R-14
 

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Discussion Starter #5
too bad there is no 235 65 14. The 235 60 14 will be 6% off on the speedo....it will show 60mph when your going 56.4. That is significant
 

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I have 14x7 wheels

Running: 14x7 Rally II 245x60x14
They look great, wide and fit great in the wheel-wells

As far as speedo. TH 400...3.55 rear... Spot on up to about 58 mph then at 60 off by about 2mph. Am using the 45 tooth driven gear I think its the light blue one.
 

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Discussion Starter #8
I have 14x7 wheels

Running: 14x7 Rally II 245x60x14
They look great, wide and fit great in the wheel-wells

As far as speedo. TH 400...3.55 rear... Spot on up to about 58 mph then at 60 off by about 2mph. Am using the 45 tooth driven gear I think its the light blue one.
does the 245 tire bubble out a lot past the rim? Like look strange or no?
 

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Pick up some 15x7 rally II's off craigslist and you'll have an almost endless tire selection. :cheers
 

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Discussion Starter #11
hey guys, one more thing. Does anyone have any pictures of a GTO with staggered wheels? I am looking at 15 out front and 17 in the back with the Ridler 675 rims. They look like nice wheels with a good price tag
 

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hey guys, one more thing. Does anyone have any pictures of a GTO with staggered wheels? I am looking at 15 out front and 17 in the back with the Ridler 675 rims. They look like nice wheels with a good price tag
Why not the same rim size all around, at least in diameter? You can get the ride height you want with proper spring selection and aspect ratio on the tires. If it was a street rod or something I could understand but not on a GTO.

The rims you have chosen look nice but I've never heard of Riddler. Where are they made? You might want to consider a wheel manufacturer with a track record and maybe made in the USA (or Canada). I just don't trust Chinese anything.
 

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Discussion Starter #14
Why not the same rim size all around, at least in diameter? You can get the ride height you want with proper spring selection and aspect ratio on the tires. If it was a street rod or something I could understand but not on a GTO.

The rims you have chosen look nice but I've never heard of Riddler. Where are they made? You might want to consider a wheel manufacturer with a track record and maybe made in the USA (or Canada). I just don't trust Chinese anything.
If i run a taller 15 in front and a shorter 17 tire out back won't it end up being the same diameter? Also, do you have a suggestion on a decently priced domestic rim?
 

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On the front of my 69, I'm running p245/60-15's on 15X7 Rallye II's (4.25" back spacing). On the rear I'm running P275/60-15's on 15X8 Rallye II's (4.5" back spacing). Everything fits and doesn't rub.
I've got 3.50 rear gears, TH400 with either the "purple" or "green" (I forget which one, exactly) driven gear, and my speedo is close to dead on. An indicated 70 is actually about 71, 71.5.

Let me see if I can dig up a photo with a decent view of the tires and wheels...




Bear
 
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