Confused on tyres sizes

[michael pash]

Sorry if this has been done to death.. couldn't find an answer in the search.

I'm buying some winter wheels (Fox ms007) and getting some mitchlin alpine 4 tyres 225 40 18.

I have 2 options 18x8 et45 and or 18x8.5 et45 both to run the same 225 40 tyres.. what's the difference?

My line of thought was 18x8 front 18x8.5 rear as I think that'll make a better stance but how does the tyre size being the same on both effect anything?

Car suspension is completely standard

 

[SM18]

If your running 225 tyres I would say 8” personally

 

[AlS3BE]

On a 225 tyre on a 8.5” wide rim you will get that euro look.
Like this

https://313368a9b4e62fc9edf0-b6f260...bd07a.ssl.cf3.rackcdn.com/1453369970_FZNq.jpg

Maybe not that exaggerated but you get the picture.
On a 8” wide wheel you will get that oem look where the sidewalls stand more straight. And it will give the better rim protection.
Some tyre fitters will struggle getting a narrow ish tyre on a wide rim if they don’t know what they are doing and will risk damaging the wheels.
Assuming you have a 3/5door hatchback then standard a3/s3 is 51 offset/7.5wide so with a 45 offset/8” wide wheel it will stick out further about 12mm and 8.5” wide will stick out about 18mm over the where the standard wheels sit. This could increase stone chipping if the side and rear of the car as more crap like grit can get thrown up.
I’ve been looking at winter wheels for a bit so going to try and get oe wheels as not many do a 50 ish offset on a 7.5” wheels.

 

[michael pash]

On a 225 tyre on a 8.5” wide rim you will get that euro look.
Like this

https://313368a9b4e62fc9edf0-b6f260...bd07a.ssl.cf3.rackcdn.com/1453369970_FZNq.jpg

Maybe not that exaggerated but you get the picture.
On a 8” wide wheel you will get that oem look where the sidewalls stand more straight. And it will give the better rim protection.
Some tyre fitters will struggle getting a narrow ish tyre on a wide rim if they don’t know what they are doing and will risk damaging the wheels.
Assuming you have a 3/5door hatchback then standard a3/s3 is 51 offset/7.5wide so with a 45 offset/8” wide wheel it will stick out further about 12mm and 8.5” wide will stick out about 18mm over the where the standard wheels sit. This could increase stone chipping if the side and rear of the car as more **** like grit can get thrown up.
I’ve been looking at winter wheels for a bit so going to try and get oe wheels as not many do a 50 ish offset on a 7.5” wheels.

That's a big help thanks.. if I got 235 40 tyres then on the 8.5 it'll be more oem look

Would it be stupid to do front 18x8 225 40 18 and 18x8.5 with 235 40 18 or would that give me a staggered oem look

 

[michael pash]

On a 225 tyre on a 8.5” wide rim you will get that euro look.
Like this

https://313368a9b4e62fc9edf0-b6f260...bd07a.ssl.cf3.rackcdn.com/1453369970_FZNq.jpg

Maybe not that exaggerated but you get the picture.
On a 8” wide wheel you will get that oem look where the sidewalls stand more straight. And it will give the better rim protection.
Some tyre fitters will struggle getting a narrow ish tyre on a wide rim if they don’t know what they are doing and will risk damaging the wheels.
Assuming you have a 3/5door hatchback then standard a3/s3 is 51 offset/7.5wide so with a 45 offset/8” wide wheel it will stick out further about 12mm and 8.5” wide will stick out about 18mm over the where the standard wheels sit. This could increase stone chipping if the side and rear of the car as more **** like grit can get thrown up.
I’ve been looking at winter wheels for a bit so going to try and get oe wheels as not many do a 50 ish offset on a 7.5” wheels.

Also I drive a saloon

 

[Flying Scotsman]

I would go with 225/40/18 and 8" wide rims...tyres are cheaper and give better traction for winter tyres, over 235 width.

 

[AlS3BE]

Staggered tyres will throw your abs out as the front and back will spin at different speeds. Could also cause damage to Quattro systems.

 

[michael pash]

Thanks for the advice.. I've decided either 18x8 with 225 40 18 tyres all round or 18x8.5 with 235 40 18 tyres all round

 

[AlS3BE]

If it’s winter tyres you will be better using a narrower tyre and that will be better for for rain/snow. The 235 will also knock your speedo out. Not by much.

 

[michael pash]

If it’s winter tyres you will be better using a narrower tyre and that will be better for for rain/snow. The 235 will also knock your speedo out. Not by much.

Thanks for the advise.. kept all corners the same but gone 18.8.5 235 40 tyres.
Tbf the only availability was a 18.x8.5 wheel in hyper silver so didn't want to strech a 225
Thanks for the advise.. you can thank me for a lovely mild winter now!

Ordered fox ms007 with mitchlin alpin 4 tyres so hoping it'll look good against the Daytona grey and handle the winter comfortably

 

[AlS3BE]

Just make sure it doesn’t stick out too far or foul the suspension on the inside. If I remember right it’s a mot failure if you can see tread on a birds eye view. Not sure what kind of clearances there are on the s3.

 

[Lehn]

Just make sure it doesn’t stick out too far or foul the suspension on the inside. If I remember right it’s a mot failure if you can see tread on a birds eye view. Not sure what kind of clearances there are on the s3.

Wont' be a problem on the S3, see my sig for spec: