Tyre Sizes

[shimee]

Hi All,

Forgive the noob question but looking ahead to first tyre swap and am curious if the rim size absolutely dictates the tyre width one can fit? I expect it would but am wondering if there is any tolerance for a slight wider tyre on the stock Talladega rim. Ideally I will be upgrading wheels at the same time as the tyres but wanted to understand this point.

Thanks

[Perun]

Manufacturers don't really get to have much a say in this because this is regulated by the Tyre and Rim Association of Australia. What they say is gospel.

To save me typing up 4-5 paragraphs (not much time) explaining the legalities of it, you can legally go up to a 245/35R19 on the existing rims, on your car. If you go any wider on the existing rim, the aspect ratio will need to go up, thus bringing the overall height of the tyre up and exceeding the 15mm increase legal limit on the overall height.

Just make sure the load and speed ratings on the new tyre are suitable.

[Perun]

Dylan, do you mind sharing with me where you're getting this information from?

A link to a site would be fantastic, as I'd love to read up on this rule that no one knows about.

And please don't tell me it's tirerack.com, which is a privately owned business in the US.

[dylan8]

[Perun]

Dylan, I am going to PM you with and we can discuss this further off the forums, but I have no idea where you're getting this from. Dunlop aren't sure either because I spoke to them not long ago and they have confirmed that 245/35R19 Dunlop Sport Maxx TT IS a legal fitment, which I knew anyway. No tyre manufacturer I have ever dealt with (which is probably 80% of them) has specifically stated that they forbid certain fitments. They might make a recommendation but they cannot override Australian law.

Once again: in Australia this is regulated by the Tyre and Rim Association of Australia. This is GOSPEL. The whole industry works off their manual, as do the tyre manufacturers, as do I.

Incidentally, my 2012 copy of the TRAA manual is due to arrive any day now. I can forward you the relevant section for your perusal if you wish.

[Diesel_vert]

Hi All,

Forgive the noob question but looking ahead to first tyre swap and am curious if the rim size absolutely dictates the tyre width one can fit? Ideally I will be upgrading wheels at the same time as the tyres but wanted to understand this point.

The width (235) and profile (35) mainly dictate what wheel width the tyres can be fitted on.

Brand doesn't matter because it's mostly consistent between the tyre manufacturers. The great majority of them follow one or more of the standards manual published by the ETRTO, TRA or JATMA (the three major ones) which are broadly consistent with each other.

The standards manual also allows for some tolerance in tyre section width and diameter, so you can get tyres that are slightly smaller or larger than the nominal dimensions (within the same size). This may make all the difference between rubbing and not rubbing, but it's largely determined by experience and/or trial & error.

... but am wondering if there is any tolerance for a slight wider tyre on the stock Talladega rim.

Assuming you have 8.0 J x 19 wheels, you may fit 245/35 R19 93Y XL tyres, but not sure if they'll rub.

255/35 R19 96Y XL tyres should only be fitted on 8.5 J x 19 wheels or wider.

no you cant, depends on the tyre brand as I said before.

for example a Dunlop SP Sport Maxx TT 245/35/19 CAN NOT be legally fitted to a 19x8 wheel. the wheel width range of that tyre is between 8.5 and 10"

There is a massive error in Tire Rack. Some of specs for the Dunlop SP Sport Maxx TT in 245/35 R19 are mixed up with 255/35 R19. I checked with the manufacturer's U.S. website to verify this.

For instance, the figures listed in Tire Rack for "Rim Width Range", "Meas. Rim Width", "Sect. Width", "Tread Width", "Overall Diam." and "Revs Per Mile" are for 255/35 R19 tyres.

[jamesdavid]

Just remember the legality side of things, so many people these days slam wider and larger wheels on not taking into consideration the roadworthy aspect of it.

Legally you can only go 2 inches over the largest tyre size listed on your tyre placard. And when i say 2 inches that doesn't mean from a 17 to a 19, you can only go 1 inch larger in diameter and 1 inch larger in width. And no, spacers are not roadworthy either lol, not unless you can provide an engineering certificate for them which i don't see why you would go to the trouble of doing it.

Hope that helps,
James

[shimee]

Thanks for the replies guys - seems there is consensus on 245 being max possible with the stock rims...something to keep in mind come time to change em out. But then, seeing cars like rev555 and 10d makes me think the wheels need to go anyway. Should sue them for loss of income

[Diesel_vert]

Thanks for the replies guys - seems there is consensus on 245 being max possible with the stock rims...something to keep in mind come time to change em out. But then, seeing cars like rev555 and 10d makes me think the wheels need to go anyway. Should sue them for loss of income

Lol, nothing drains the savings like the car modding scene!

[Perun]

Just remember the legality side of things, so many people these days slam wider and larger wheels on not taking into consideration the roadworthy aspect of it.

Legally you can only go 2 inches over the largest tyre size listed on your tyre placard. And when i say 2 inches that doesn't mean from a 17 to a 19, you can only go 1 inch larger in diameter and 1 inch larger in width. And no, spacers are not roadworthy either lol, not unless you can provide an engineering certificate for them which i don't see why you would go to the trouble of doing it.

Hope that helps,
James

James, that 1" rule is also incorrect. You are allowed to go 15mm up on the tallest tyre & wheel combination rolling diameter available for that car, regardless of size. You are correct on the width though.

[jamesdavid]

thanks for the correction Perun , always a good thing to know. i had this arguement with the roadworthy tech at work who claimed the one inch larger in diameter whereas i said what does it matter if i go from higher aspect ratio smaller diameter wheel to a lower aspect ratio wheel with a larger diameter? the actual size change of the wheel/tyre wouldn't be of great difference. Provided that the load rating and speed rating were still in spec.

Cheers Again.

[Golf16SE]

Hey guys I need some help, I'm just about to buy some oem 19x9 offset 29 Audi rs4 wheels, All tyres are 275 x 30x 19s. ... Do u guys think it might rub and will it poke out abit ??? Plus ill have the h&r springs in ?
Thanks

[team_v]

Hey guys I need some help, I'm just about to buy some oem 19x9 offset 29 Audi rs4 wheels, All tyres are 275 x 30x 19s. ... Do u guys think it might rub and will it poke out abit ??? Plus ill have the h&r springs in ?
Thanks

They will definitely poke with that offset.
Also i believe RS4 wheels are 5x112 so won't match a Mk4 golf (assuming that is what you have due to your avatar picture)

[Golf16SE]

Wheels

Lol no sorry I did forget to mention I have a scirocco r... That's what the topic is about ..?? So what u think ?

[Andych]

19x9 with 29 offset with 275 tyres will definitely poke.....

Use this tool to make the comparisons
Custom rims, wheel tire packages for your ride - RIMSnTIRES.com That one isnt working properly for me...
Online Wheel & Tyre Fitment calculator. Offset, Tyre stretch and Rolling Radius calculator This one says the difference in poke will be 25mm per side.