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New wheels, need some help

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Old Sep 5, 2003 | 06:43 PM
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Default New wheels, need some help

I was looking at some new wheels for the bonnie and wondering what was the max size I could go. I haven't found anyone with anything bigger than 18 x 8.5... can anyone confirm? The rims I was looking at are 18 x 7.5, I know these will fit, but I'm not sure on tire sizes, kinda confused with the numbers. My options are 225/40/18, 215/35/18, 235/40/18, and 245/40/18. I'm looking for a prettly low profile tire, but not so small that I bend the rims if I hit a pot hole. Can someone tell me which of the tires is the smallest and which is the largest (as far as profile)?

Thanks.
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Old Sep 5, 2003 | 08:41 PM
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dubs will fit! but with 35 series tire
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Old Sep 6, 2003 | 12:12 AM
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Oh really? So 20'* would fit... whats the max width of the wheel that can fit, 9? 9.5?

Thanks again.
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Old Sep 6, 2003 | 12:31 AM
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I think the max width was 235s and 245 with minor ajustments and 255s with major ajustments.
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Old Sep 6, 2003 | 01:54 AM
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i may be wrong but check your local rim shop for details?
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Old Sep 6, 2003 | 12:17 PM
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255'* take work, SSEi95 from here has them on his, on stock rims (look like their flat...) i think 235 will work fine, 245 will need some adjusments for when you're turning and/or shocks compressing, and 255'* need the wells pushed back a little.
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Old Sep 6, 2003 | 02:26 PM
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Ok so the 20'* I'm looking at are 20 x 8.5 and the tires that they come with are either 255/35/20 or 245/35/20... so what adjustments would need to be done in order to make the 245'* fit? Is it possible to do them by myself or would it require taking the bonnie to the shop? I'm still kinda confused on how the numbers work for tires... if the wheels are 8.5", then why does it matter if the tires are 255 or 245?

Thanks for all your help guys.
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Old Sep 6, 2003 | 05:23 PM
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The numbers for tires work line this: i.e. 245/35/20

245 = tire width in millimeters
35 = percentage of height to width (also known as aspect ratio) the side wall height is 35% of the width (again, in millimeters)
20 = rim diameter (in inches)

Using this, you can calculate the total overall diameter of the tire mounted on the rim.

2 x tire height + rim = total diameter
2 x ((.35*245)/25.4)+20=
2 x ((84.75)/24.5)+20=
2 x (3.337)+20=
6.674+20=26.674"

The reason this number is more important than the tire/rim width is that the more it differs from your stock tire/rim defines how far off your speedometer will be. As far as any interference based on the width of the tire, the tire shop should be able to tell you how it may compare to the stock rim/tire. They should be able to tell you if a different offset rim is needed.

Worst case scenario would be to install the new rim/tire on the front and try turning ti lock-to-lock and watching for any rubbing ro interference.

Jay
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Old Sep 7, 2003 | 04:21 PM
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You also have to consider if the wheels will rub when the shocks are compressed.
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Old Sep 7, 2003 | 05:01 PM
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The strutes on your car compress?? serous?? go lean the on the front bumper of your car I hope it doesnt go down less then a centimeter
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