225/50/17 vs 225/45/17 winter tires

[mishonio]

The 17" audi B8 wheels which I just bought from an Audizine member to use during the winter are meant for tire size 225/50/17.

To fit my spiker spider chains though, I was thinking of going with a slightly lower tire: 225/45/17.

Will there be issues if I go with 225/45/17 instead of what Audi puts on these wheels which is 225/50/17?

Thanks,
Michael

[rollerton]

No, that's hardly a difference- and you're not even changing the OEM width, just the aspect (sidewall) by 5%, which for a 225 is...roughly 5mm in diameter. As long as all the tires are the same size, no problem.

[mishonio]

Thanks Rollerton.

So there should be no issues with the indirect TPMs or other systems...

[neptunesfinest]

Might have a slight effect on the speedo and odo due to the smaller diameter.

[cory_can]

I've never used chains (not legal here in Ontario) but I would assume the chains would add extra rolling diameter to the wheel to offset any difference caused by the lower profile tire.

[dame drizzo]

I've never used chains (not legal here in Ontario) but I would assume the chains would add extra rolling diameter to the wheel to offset any difference caused by the lower profile tire.

Why is it illegal? They have ones don't damage the road. Seen them on ecs tuning...

[DeMOROlized]

Why is it illegal? They have ones don't damage the road. Seen them on ecs tuning...

Uh, they are illegal because the local law says so.

[equ]

I would only put the 225/50-17, a specified size. The 225/45-17 size is simply wrong and not that close. It also won't match the spare should you need it.

[mishonio]

I would only put the 225/50-17, a specified size. The 225/45-17 size is simply wrong and not that close. It also won't match the spare should you need it.

Good point.

My car though has the 4 spoke factory 18" wheels with the Pirelli P6 245/40/18. I guess the spare is designed to match this tire size.

I am now buying a winter setup (17" wheels+tires). Already bought the 17" original Audi wheels. For the tires, regardless of whether I go with 225/45/17 or the Audi default, slighly taller 225/50/17, the spare perhaps will not match anyway.

Am I missing anything? Why using a slightly lower tire will be wrong?

[equ]

Both 245/40-18 and 225/50-17 are factory sizes. They are very close to each other and the spare will work with both. I assume all a4's are shipped with the same spare and some cars come with 17's and some with 18's. I run 245/40-18 in the summer and 225/50-17 in the winter. The other allowed sizes are 245/45-17 and 255/35-19. Aren't four sizes enough choice? Do not stray.

[cory_can]

Both 245/40-18 and 225/50-17 are factory sizes. They are very close to each other and the spare will work with both. I assume all a4's are shipped with the same spare and some cars come with 17's and some with 18's. I run 245/40-18 in the summer and 225/50-17 in the winter. The other allowed sizes are 245/45-17 and 255/35-19. Aren't four sizes enough choice? Do not stray.

There are plenty of sizes that are well within specs. Just 2 examples....my winters are 225/45/18 which is fine....245/35/19 is also common and perfectly fine.

[mishonio]

Thank you all for the responses.

[brainpan]

Why is it illegal? They have ones don't damage the road. Seen them on ecs tuning...

theyve been banned since the 70s , they basically said that the damage they cause compromise the road safety and that they didnt offer any big safety advantages that out way the damage cause to the road

110$ ticket, plus theyd probly tow the car until the studs are removed, pretty sure ontario is the only place that they are banned in canada, well theyre actually legal in northern ontario... if that makes any sence

[equ]

There are plenty of sizes that are well within specs. Just 2 examples....my winters are 225/45/18 which is fine....245/35/19 is also common and perfectly fine.

Agreed that those two sizes also work. But really the choice is not infinite and if OP is questioning whether 225/45-17 is acceptable, I don't want to give the impression that "lots of sizes work". I personally don't go with diameter even but revs per mile (listed in specs in tirerack.com). So e..g. 245/40-18 is 805 revs per mile and 225/50-17 is about 803 (and then there is variation by manufacturer and of course tread wears out). I'd personally stay in the 800-810 range on this car.