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Hi guys,

Quick question, I'm goin to get some Yokohama Advan v103's fitted this weekend, and am currently running 17 x 9 te37's, jsut wondering what would be the best width to go for 245 or 255, and what differences the extra 10 mil will make in handling / ride quality.

Any help will be appreciated.

Cheers,

Dave.

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With 245/40R17, your speedo will read 0.65% faster. 627.8mm rolling diameter

With 255/40R17, your speedo will read 0.62% faster. 635.8mm rolling diameter

Stock 205/55R16 is 631.9mm rolling diameter. Bees dick in it

Different rolling diameters cause speedos to be out by a percentage not a static amount

You've got the wider rim, may aswell use it and get the wider rubber if they're the same price. If it was me, I'd get which ever is cheaper though :happy:

Edited by salad
With 245/40R17, your speedo will read 0.65% faster. 627.8mm rolling diameter

With 255/40R17, your speedo will read 0.62% faster. 635.8mm rolling diameter

Stock 205/55R16 is 631.9mm rolling diameter. Bees dick in it

Different rolling diameters cause speedos to be out by a percentage not a static amount

You've got the wider rim, may aswell use it and get the wider rubber if they're the same price. If it was me, I'd get which ever is cheaper though :happy:

i think standard GTR tyre size is 225.

personally I think on a 9inch rim on a GTR go the 245. but there is not much in it. and some brands 245 will have as much tread with as another brands 255. if there is much of a price difference just get the 245. if there is not much difference get the 255.

i think standard GTR tyre size is 225.

personally I think on a 9inch rim on a GTR go the 245. but there is not much in it. and some brands 245 will have as much tread with as another brands 255. if there is much of a price difference just get the 245. if there is not much difference get the 255.

Oh whoops didn't realise that he had a GTR. Anyway, 225/50R16 is 0.5mm smaller than 205/55R16, or 0.08% so all calculations hold

Lucky me :D

Edited by salad

thanks for hte replies guys, but i guess what im trying to ask is what kind of influence on ride / handling will different sized rubber stretched over the rim produce?

for example will wider tyres cause the car to tramline more, or will they provide more grip? what are the advantages/disadvantages of going the wider or the narrower tyre on the rim?

Cheers,

Dave

Get 255's.....they are perfect for a 9" rim. If you use 245's the rim protector bead around the tyre does not stick out past the rim like it's suppose to.

The price difference between the two is minimal because 255's are commonly used now. I went 265 last time and the price jump was HUGE because 265 is not a common size. I will go back to 255 next time because there is buggerall difference for a road car and I can't justify the large price hike for 265's

mmmm, i see most of you guys running 40 profiles. I have 17x9's with 45 profiles all round as i thought this was the norm?

I have power fc and my speedo doesn't seem to be out too much? i do run 235's if that makes a difference and its a gtst!

Edited by mr_rbman

The profile or aspect ratio is a ratio of the tyre width. So a skinnier tyre with a higher aspect ratio can have a similar diameter to a wider tyre with smaller aspect ratio.

Eg. 205/55R16 is almost identical to 225/50R16 in rolling diameter.

225/45R17 is almost identical to 255/40R17

etc

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