Tire size on 8.5 x 18?
06-01-2004, 06:28 PM
#2
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The tread is 2" wider than the wheel. It will fit, but not optimally and you'll probably have some clearance issues with fender and suspension if you put it on the front.
06-01-2004, 08:18 PM
#4
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I use a 275 tire on a 9" wheel (on the Cobra), and it is a perfect match. I would think a 265 would work on your 8.5" wheel. Phil has those on his "stock" C4S, but he's probably running some fairly agressive camber, which can help with tire rub issues.
I have 8.5" wheels, and have stretched my old 225 tires on them. They are WAY too skinny for that wheel. I wonder if all 8.5" wheels are created equally? From my perspective, the perfect tire size would be a 255x35x18.
I have 8.5" wheels, and have stretched my old 225 tires on them. They are WAY too skinny for that wheel. I wonder if all 8.5" wheels are created equally? From my perspective, the perfect tire size would be a 255x35x18.
06-01-2004, 09:19 PM
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Originally posted by 911/Q45
The tread is 2" wider than the wheel. It will fit, but not optimally and you'll probably have some clearance issues with fender and suspension if you put it on the front.
The tread is 2" wider than the wheel. It will fit, but not optimally and you'll probably have some clearance issues with fender and suspension if you put it on the front.
The ideal tire width for a 8.5" rim is 225mm or 235mm. Although a 265 can be shoe-horned on, the tire is very pinched and will not perform as well as a smaller tire. I would not go any larger than 245 if performance is a major concern.
BTW, a 8.5" Porsche rim is measured the same way a 8.5" Ford rim is measured... it's a standardized measurement.
06-02-2004, 12:14 AM
#6
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My Mustang came stock with 8" wheels and 245 tires. 225s are way too skinny for an 8.5" rim. The thing thats a bit confusing is that the Kinesis 8.5" wheels look so much wider than the factory 8", using the 225 tire as the basis for comparison.
06-02-2004, 12:24 AM
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Originally posted by ca993twin
My Mustang came stock with 8" wheels and 245 tires. 225s are way too skinny for an 8.5" rim.
My Mustang came stock with 8" wheels and 245 tires. 225s are way too skinny for an 8.5" rim.
Seriously, if you don't believe me contact a couple of competition tire manufactures and ask them what tire size is optimal for a 8.5" rim... they will tell you 225-235.
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06-03-2004, 12:21 PM
#8
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Wet1,
My point is that car manufacturers tend to be fairly conservative with their choice of tire size/wheel size. The fact that the Mustang did or did not handle like crap was not because of 245 tires on 8" wheels...
Is everyone aware that the numbers we are tossing about (225, 245, etc) are the SECTION width, not TREAD width? The section width is the widest "bulge" of the tire in the sidewall, and to flex properly, should be wider than both the rim width and the tread width.
My point is that car manufacturers tend to be fairly conservative with their choice of tire size/wheel size. The fact that the Mustang did or did not handle like crap was not because of 245 tires on 8" wheels...
Is everyone aware that the numbers we are tossing about (225, 245, etc) are the SECTION width, not TREAD width? The section width is the widest "bulge" of the tire in the sidewall, and to flex properly, should be wider than both the rim width and the tread width.
