[Moe]

Hi guys i have just ordered my new wheels finally found a supplier for them

They are 20x9 and 20x10.5"

Now what tyre size do i have to run???

Will 275/30/R20 rub on the rear of e93??

At the front i want to run 245/30/R20

Any help at what tyre sizes i need as i am looking to order today???

[creepy coupe]

265/30/20 rear

225/35/20 front will give the closest RR

[Moe]

265 30 wont that be a bit too stretched???

275 to big??

[creepy coupe]

275's would be better, but might rub, depends on the offset.

Ian, Hotcoupe is the man to ask

[E92Fan]

Incorrect tyre profiles above -

Standard 19" rear wheels are either 255/30 or 265/30

Therefore for 20" wheels you need 275/25 to maintatin the correct speedo reading, otherwise you'll be around 4.5% out of calibration.

For 10J x 20", a 275 wide tyre will fit fine, and as long as the offset is close to ET40, you should have just enough clearance at the back as long as the car isn't lowered. If the car is lowered, then you'll need to have the inner rear arches rolled.

The fronts will work fine on a 245/30 tyre, assuming the front offset is again ET40
(225 section is too narrow on a 9J wheel)

[Moe]

The rear et is 35 and the car is on standard m sport suspension is convertible so quite low.

Ideally i want 275/30/r20 this is mainly because the tyre size is more commonly found also i get a bit more sidewall and if the 275 will be slightly stretched over the 10.5j wheel then it should not rub???

265 way to small???

[creepy coupe]

Are you sure Tone? The calculators I've used have the 265/30/20 as .89% difference and 275/25/20 has - 2.36%

Based on a 255/35/19

[E92Fan]

Originally Posted by creepy coupe

Are you sure Tone? The calculators I've used have the 265/30/20 as .89% difference and 275/25/20 has - 2.36%

Based on a 255/35/19

But the standard rear tyres aren't 255/35/19 - they're 255/30/19 !!

[creepy coupe]

Originally Posted by E92Fan

But the standard rear tyres aren't 255/35/19 - they're 255/30/19 !!

I knew that

[E92Fan]

Originally Posted by Moe

The rear et is 35 and the car is on standard m sport suspension is convertible so quite low.

Ideally i want 275/30/r20 this is mainly because the tyre size is more commonly found also i get a bit more sidewall and if the 275 will be slightly stretched over the 10.5j wheel then it should not rub???

265 way to small???

Ah shit.. I misread your initial post - so it's a 10.5J wheel at the back?

Definitely need 275 or 285 tyres then. 265 way too small. But you will have a major problem with the offset.


Firstly, the tyres - the original 19" rear wheels on a BMW use 255/30/19 tyres. Going to a 275/30/20 (so keeping the sidewall profile the same but going to a 20" wheel) will result in your speedo under-reading by 5.56% - so when the speedo reads 60mph, you're actually doing 63mph!!

That's why you should use a 275/25/20 tyre size.


But the bigger problem is the offset - you have an ET35 offset rear wheel, 10.5J wide, and that simply won't fit - it'll be far too wide into the arches as it will sit 23mm further out, and even if you rolled the rear arches I think you'll still have a problem. With 10.5J wheels you need as minimum ET40 rear wheels, and still need to roll the arches.

[- Paul -]

Use the calculator here ~:
http://www.e90post.com/forums/forumdisplay.php?f=12

[E92Fan]

Originally Posted by - Paul -

Use the calculator here ~:
http://www.e90post.com/forums/forumdisplay.php?f=12

Doesn't go down to 25 profile tyres though!

[Moe]

What et do i need for the wheel to fit then close to et40?? thats not a problem as i can get the offset closer to et40??

I have heard that a 10.5 rear wheel with a 285/25/20 rubs on the inner edge so technically by getting a higher offset the wheel rub on the inner edge more if i am thinking correct???

[E92Fan]

Originally Posted by Moe

What et do i need for the wheel to fit then close to et40?? thats not a problem as i can get the offset closer to et40??

I have heard that a 10.5 rear wheel with a 285/25/20 rubs on the inner edge so technically by getting a higher offset the wheel rub on the inner edge more if i am thinking correct???

The inner edge? Do you mean the rear wheelarch bodywork, or do you mean rubbing on the strut ?? And what offset did that wheel you heard about have? Your statement isn't much help without the details

A 10.5J with 285 section tyre will rub on the wheelarch if you have a low ET - the higher the number, the further in to the centre of the car the wheel sits, therefore giving you more clearance by the wheelarch. However too high an offset number will give you clearance issues on the strut side.

With a 10.5J wheel, on 275 tyres, you should be ok with an ET42, but you'll still need to roll the rear arches and probably dial in a bit more negative camber than standard. You'll wear the inner edge of your tyres quite a bit quicker so beware of that.

Do you have to use a 10.5J wheel? Can't you get a 10J wheel? It'd be a hell of a lot easier to fit - 10J with ET40 on 275/25/20 tyres...

[marconi118]

I have done 235/30/20 + 255/30/20 on 8,5x20ET40

Tires stretched in the front, perfect on the rear(tire protecting wheel). No problem for the rolling diameter difference F/R on a RWD 335I it is ok

No fender rolling

Get 9,5X20 ET35 or 37 and put 255/30/20 a lot cheaper than 275/25 and more profile choice

In the front go for 235/30/20 or 235/35/20 on 8 or 8.5x20

[willhollin]

This guy ran 20" on his E93

http://www.e90post.com/forums/showpo...8&postcount=27

[Hotcoupe]

Originally Posted by willhollin

This guy ran 20" on his E93

http://www.e90post.com/forums/showpo...8&postcount=27

Trouble is the tyres rubbed!

As Tony has already stated 10.5J rims with an ET35 will rub.

Moe, for info my G-Powers are (rear) 9.5J/ET46/275 tyres and they don't rub.

As Tony has alreay said a 10.5J rim will cause you grief even with a higher offset (42+).
Get your arches rolled, it's no big deal:

http://www.archenemy.co.uk/index.htm

[Moe]

The guy i have heard of through my cousin said that the wheels rubbed on the inner arch at the back not the strut but the matting of the arch i.e arch rolling.

The wheels i am getting are et35 rear however i can get a high offset say et40 i dont mind rolling the arches as long as the just rub on the arch not the arch lining.

I cant get the wheels i want in 10j if i could i would of theres wheels i really really like and have taken me more than 6months to source after being messed about by suppliers etc etc

So higher offset and basically get the arches rolled right will arch roll effect my warranty its a 09 car

Also so what tyres are exactly recommended as i would liek to order my tires tomorrow

thanxx guys i really appreciate the help

[Hotcoupe]

Originally Posted by Moe

The guy i have heard of through my cousin said that the wheels rubbed on the inner arch at the back not the strut but the matting of the arch i.e arch rolling.

The wheels i am getting are et35 rear however i can get a high offset say et40 i dont mind rolling the arches as long as the just rub on the arch not the arch lining.

I cant get the wheels i want in 10j if i could i would of theres wheels i really really like and have taken me more than 6months to source after being messed about by suppliers etc etc

So higher offset and basically get the arches rolled right will arch roll effect my warranty its a 09 car

Also so what tyres are exactly recommended as i would liek to order my tires tomorrow

thanxx guys i really appreciate the help

Moe, you'll need a 275 tyre, the 265 will be too stretched & the 285 will cause you too many problems with your arches.

You'll struggle to get a 275/25/20 tyre, so you'll have to go 275/30/20 and accept a slight degree of inaccuracy in your speedo reading.

The higher offset on the wheels the better in your case,certainly 40+.

In terms of warranty there is not much that could be affected by rolling the arches and it would not really show in any way either.

Kevin @ Birds will roll your arches:
http://www.birdsauto.com/

As a matter of interest what wheels are they?

[E92Fan]

Originally Posted by Hotcoupe

Moe, you'll need a 275 tyre, the 265 will be too stretched & the 285 will cause you too many problems with your arches.

You'll struggle to get a 275/25/20 tyre, so you'll have to go 275/30/20 and accept a slight degree of inaccuracy in your speedo reading.

The higher offset on the wheels the better in your case,certainly 40+.

In terms of warranty there is not much that could be affected by rolling the arches and it would not really show in any way either.

Kevin @ Birds will roll your arches:
http://www.birdsauto.com/

As a matter of interest what wheels are they?

The problem with using a 275/30/20 tyre is you will be making it even harder for the rear wheel to fit under the arches. The wheel/tyre combination will be that much bigger, never mind the HUGE inaccuracy in the speedo.


You must really try to find a 275/25/20 tyre, and I've done a little searching for you and have found the following:


There is a 275/25/20 tyre by Dunlop called the Sport Maxx GT. Available on mytyres.co.uk

There is also a 275/25/20 by Yokohama called the Advan Sport V103, available from Elitedirect.com

If you really can't find anything in the 275/25 fitting, then you should go for a 285/25 as opposed to a 275/25 - it'll be easier to fit. In this case, make sure the offset is at least ET42 to give yourself the most chance!

285/25 tyres are widely available in many different brands. Use the links I've given above to have a search.

The front tyres will depend on what rear tyres you use. If you do go with a 275/25 then the front should be a 235/30

If the rears are a 285/25, then the fronts should be a 245/30 to maintain the same rolling circumference.



So, bottom line -


Best configuration -

Front - 235/30/20
Rear - 275/25/20


Second best configuration -

Front - 245/30/20
Rear - 285/25/20

[Moe]

Thank you guys so if i use the 275 tyre will i have rubbing if the offset is say et40??

I will clear the inner strut and arch matting but have to get the arches rolled Is this correct??

275/30/20 is the size i was cosidering becuase fo the falken 452 tyre as if the tyre is slightly stretched and as falken come ith a curved sidewall then technically it should give me clearence due to the type of tyre???

However i will look at getting the 275/25/20

[marconi118]

go for 235/30/20 on 8.5X20ET35 and 255/30/20 9.5X20ET37
A lot of tire choice in 255/30/20! Go for the new Pirelli P-ZERO it is a winner better than PS2 (audi R8 OEM equipment)

Really the rolling diameter difference between front and rear doesn't matter on a RWD car. I am running this setup on my E93 335i, no DTSC failure code, nothing, and the speedometer will show you the correct speed since with OEM wheels it is overestimating it by a few % And NO fender rolling

Even the M3 has taller tires on the back (235/35/19 + 265/35/19)

on 285/25 you will loose a lot of performance, pay a lot for tires and go for fender rolling.