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germanmachine
10-04-2005, 04:23 PM
I have 18 x 8.5 wheels with 225 45 on it, will 245 45s fit on these same wheels? Or what are the fitment guidelines for wheels...
Or does it matter on your fenders

nizmosx
10-04-2005, 04:30 PM
thats not gona work, it might with spacers however your going to rub no matter what you do. 235s is pushing it. 245 is prolly a no go bro.

germanmachine
10-04-2005, 04:33 PM
ahh brutal
thanks

bitterchild
10-04-2005, 05:31 PM
205mm goes on 7.5"
225mm goes on 8"
I don't see why 245 won't go on an 8.5"

The sidewall will be larger so that may be an issue but the width is not

Yuikio
10-04-2005, 07:29 PM
^^Yeah, but 245/45s don't have the same size sidewall as 225/45s. The 45 is a ratio.

You won't be able to fit 245 under your fenders, regardless of the sidewall height.
But yeah, technically 245s will fit well on 8.5s

onemoremile
10-04-2005, 08:17 PM
225/40 or 245/35. the 35 will be a touch shorter but not a big deal.

http://www.miata.net/garage/tirecalc.html

with 245/35-18 your speedo will show 60 mph and you will actually be going 59.5 mph.

a b5 guy in chicago ran 255/40-17 all seasons at the track. he was lowered on stiff suspension and fenders were rolled. he reported that they didn't rub. my next tires will be 245/40-17 Azenis RT-615 or Toyo T1-R. i run 235/45-17 Pilot Sports now and it is damn near impossible to curb the wheels. 40k miles and not even a nick in the wheels.

mike-2ptzero
10-05-2005, 05:13 AM
Originally posted by Yuikio
^^Yeah, but 245/45s don't have the same size sidewall as 225/45s. The 45 is a ratio.

You won't be able to fit 245 under your fenders, regardless of the sidewall height.
But yeah, technically 245s will fit well on 8.5s

Correct, the 245/45 will have more sidewall vs the 225/45 which is why the 245 tire is taller over all vs the 225 if both are 45's. 45 is just the % of the tread which is the # before it.

On the A4 the tires for a 18" rim should have a 40 series tire, and that 8.5" rim should get no less then 235 or 245's because 225's will be a stretch.

diegomatrix
10-05-2005, 07:45 AM
on 17" rims..with 8.5 width

height differences between 225/45 and 235/40?

marginal?

onemoremile
10-05-2005, 07:58 AM
you didn't see the link i posted?

http://www.miata.net/garage/tirecalc.html

225/45-17 and 235/40-17 difference in revs per mile is 2.3%. with 235/40-17 the speedo reads 60 while you travel 58.6 mph.

bitterchild
10-05-2005, 08:10 AM
225 on an 8.5" is that stretch that the vw guys are all hot and bothered over.

mike-2ptzero
10-05-2005, 09:56 AM
Originally posted by bitterchild
225 on an 8.5" is that stretch that the vw guys are all hot and bothered over.


That is the "euro" look. No protection for the rim.

diegomatrix
10-05-2005, 10:14 AM
Originally posted by onemoremile
you didn't see the link i posted?

http://www.miata.net/garage/tirecalc.html

225/45-17 and 235/40-17 difference in revs per mile is 2.3%. with 235/40-17 the speedo reads 60 while you travel 58.6 mph.

meow~

height difference, not speed difference was what i was asking...

i forgot how the ratios were calculated..... just wondering if you placed two tires together (225/45 and 235/40), how'd their height would compare...[confused]

onemoremile
10-05-2005, 10:49 AM
check the link. height difference is calculated for you. it'll take you 2 minutes max.

BTW, difference in height is also 2.3%. math is funny like that.

also i found this AW thread regarding 255 width tires:
http://forums.audiworld.com/s4/threads/547761.phtml#1943268

Yuikio
10-05-2005, 02:33 PM
Damn, I had no idea we could go that wide. I was under the impression that 235s were stretching it. When I first put my new wheels on, (17x8, 225/45) I thought that the wheelbearing housing was really close to the tire.
My next tires will be wide.

onemoremile
10-05-2005, 02:50 PM
i searched the B5 S4 forums for 255 and found a lot more info. it looks like quite a few have gone to 245 and 255 tires. i know that the azenis rt-615 and the toyo t1-r will both fit on a 17x8" wheel nicely. the mitsu evo forums are full of folks running these two combos.

mike-2ptzero
10-05-2005, 03:51 PM
Originally posted by Yuikio
Damn, I had no idea we could go that wide. I was under the impression that 235s were stretching it. When I first put my new wheels on, (17x8, 225/45) I thought that the wheelbearing housing was really close to the tire.
My next tires will be wide.

just have to run spacers or a offset that has the wheel sitting out a little more. Only thing is you have to becarefull of how low the car is and have to roll the fender lip.