Dumb Tire Question: Any reason to match profiles F to R?
#1
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Dumb Tire Question: Any reason to match profiles F to R?
If I use a say, 35 profile tire in the rear, is there any reason why I shound/need/have to stay with a 35 up front?
Say:
285/35/18 rear (11" wheel)
245/45/10 front (8" wheel)
?
Say:
285/35/18 rear (11" wheel)
245/45/10 front (8" wheel)
?
#3
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Always been my understanding that it's best to match the outer diameter as close as you can rather than the profile. For example, the outher diameter of a 245/45 16 on the rear is within 0.3 inches of 225/50 16 on the front. If I were to try a 245/50 16 on the rear it's almost an inch taller.
You can check the specs of most size combinations on Tire Rack's website.
You can check the specs of most size combinations on Tire Rack's website.
#4
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No.
Especially with wider rears, you'll want a lower profile than the fronts to keep "similar" diameter...but not required. eg, 'Vette's come from the factory with different size, profile and overall diameter.
Especially with wider rears, you'll want a lower profile than the fronts to keep "similar" diameter...but not required. eg, 'Vette's come from the factory with different size, profile and overall diameter.
#6
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My commute to work is mostly left hand turns so I actually have taller profile tires on the ride side of my cars.
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#8
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#11
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1 You need to keep the same (ish) overall diameter both front and rear. Alternatively defined as keeping the sidewall height approx the same (if the rims are the same diameter)
2 You do know that the 35 or 45 means the height of the tyre (sidewall height if you like) is 35% or 45% or the width of the tyre.
35% of 285 = 99.75mm =3.9"
45% of 245 = 110.25mm = 4.33" = too big
a better option would be 245/40
40% of 245 = 98mm = 3.85" near enough to 3.9"
3 In the absence of any other consideration ideally you want to keep the diameter (2x sidewall height + wheel diam) about the same as the original wheels to make the speedo read correctly.
245/40/16 = 24.67" dia = original
285/30/18 = 24.72" dia = orig + 0.21%
245/35/18 = 24.74" dia = orig + 0.29%
245/40/18 = 26.67" dia = orig + 8.1%
PS corrected your typo 245/45/10 would cool on a Mini Cooper (original 1960's mini not BMW version)
Last edited by jon928se; 12-10-2011 at 04:15 PM.
#13
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#14
Nordschleife Master
Could be an issue with ABS type stuff, but otherwise in what way do front and rear tires interact, pretty much none I can think of. Right and Left on the rear you have the differential or maybe a solid axle, so same diameter is required.
#15
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Not the experience Jwise and I have. We both run 17 inch wheels/tires on the front, 18 inch on the rear. The tires have almost identical OD. I run 255/295 (F/R) for an excellent ride and handling combination.