Tyres

[JamesS4cab]

Been offered some dirt cheap 22/45/18 W Bridgestone RE040's.

I am currently running ****€ budget FULLRUN tyres but they are 235/40/18Y's and are terrible in the wet.

Am I going to cause any problems buying the Bridgestones???

 

[rashpal1]

As long as you change all four, there will be no problems.. Chaning two only will mean you have more grip either at the front or rear depending where you put them on..

Not the best thing to be doing in my opinion... i think you can get away with fitting 225/40/18 without any problems..

 

[steve_malton]

22/45/18 W? Jesus they are skinny

 

[AndyMac]

225/45/18's will be way out on rolling radius (approx 4.5% too big). 225/40/18's are the correct size.

 

[bubstar]

235/40R18 is the OE size for an 18x8 inch wheel on an A/S4.

225's are too small and what you get in the cheap replica packages.

 

[AndyMac]

Please don't start this argument again.
The original 16" alloys on a B6 are 205/55/16's (RR of 632mm), the closest to that rolling radius are 225/40/18's which are 5mm larger (+0.8%)
235/40/18's are 13mm larger (+2%)

Either will do the job, but 225's are the closest to the OE rolling radius, end of story.
Replica wheels come in this size because it's the correct size, nothing to do with cost, 235's are no more expensive.

 

[chasdrury]

So why did Audi put 235/40 on SLine B6 & 7 from the factory that had 18" alloys?

Chas

 

[quattrojames]

Please don't start this argument again.
The original 16" alloys on a B6 are 205/55/16's (RR of 632mm)

I have 215/55 x 16 fitted to mine as original equipment

 

[chasdrury]

Either will do the job, but 225's are the closest to the OE rolling radius, end of story.
Replica wheels come in this size because it's the correct size, nothing to do with cost, 235's are no more expensive.

From experience, 235/40 are more expensive than 225/40. For instance, on blackcirlces.com

Michelin PS2's - 225/40/18 (Y)XL = £127.24
Michelin PS2's - 235/40/18 (Y)XL = £158.00

Bridgestone RE050A - 225/40/18 (Y)XL - £110.79
Bridgestone RE050A - 235/40/18 (Y)XL - £133.76

Pirelli P Zero Rosso - 225/40/18 (Y)XL - £101.80
Pirelli P Zero Rosso - 235/40/18 (Y)XL - £137.33

So, 225 are certainly not the same price as 235's..

Chas

 

[chasdrury]

I have 215/55 x 16 fitted to mine as original equipment

Which a rolling radius of - 642mm

235/40/18 is 645mm
225/40/18 is 636mm

So the 235 is nearer. That's assuming that 215/55/16 is OEM - since I know 235/40/18 is factory fit for SLines, I'd say 215/55/16 is correct too...

Chas

 

[Osnim]

Not sure what model you are running, however just been through a similar experience.... I have S4 B6, and have just had to replace tyres.... On checking internet / local tyre dealers could pick up tyres at nearly 1/2 price of premium brands, which was a real temptation... bottom line if your running a powerful car, fit decent rubber.. I put on Contis, and have to say am happy that I did.. On my previous car ( scooby) I put on cheap rubber and noticed a big difference ( which is borne out in tyre reviews), so felt a bit shortchanged... it might cost extra but worth it...

size - 235 / 40 / 18 .... S4 B6...

J

 

[1.8JT]

My 04 190 s-line came from factory with michelin PS2's 235/40/18 thisis OE.

 

[AndyMac]

Goodyear F1's 225's = £101
Same in 235 = £111
So okay 10% more expensive, hardly an issue, more to do with 225's being more popular than anything else.
I'm talking about A4's which came as standard with 16" rims here folks, don't believe 16" rims were an option on an S4, it has a different gearbox for starters so can't really be used as the benchmark.
215/55/16's are definately not the correct stock size.

 

[quattrojames]

215/55/16's are definately not the correct stock size.

Where are you getting your information from?

I have that exact size on my car, the handbook sayes that and so does the little sticker on the B pillar inside the driver door shut So they are definately the correct size for my car as fitted from the factory.

 

[scottyjohn]

My B6 Avant came factory with 17" audisport alloys and have 235/45/17s as standard if it helps anyone!

 

[AndyMac]

As already said (many times) 205/55/16's are the stock tyres on my B6 TDi130, my mates Passat and another mates B6, and my B5 quattro. I know this to be the stock size as the spare has never been used, and it also refers to it in the handbook.
If you have a B6 with a 6 speed gearbox then obviously the ratios will be different so will accomodate the slightly bigger tyre. As also said before you can fit either regardless as they are both within the +/- 2.5% recommendation, but on a stock 5 speed 225/40/18's are a closer match.
Quattrojames - you have a 6speed box on a 2.5Q IIRC
On re-reading the original thread I now realise/assume the guy has an S4cab, but couldn't believe anyone would fit non-branded tyres to such a vehicle (they should be shot), so apologies as obviously the 16's I referred to are not relevant.

 

[quattrojames]

Quattrojames - you have a 6speed box on a 2.5Q IIRC

Yes I do.

As already said (many times) 205/55/16's are the stock tyres on my B6 TDi130, my mates Passat and another mates B6, and my B5 quattro.

Probably my fault for not reading the whole thread thoroughly, I guess 205/55/16's are the stock size for some A4's, but worth clarifying that not all A4's with 16" wheels run this size.

:thumbsup:

 

[NOLOGY]

KAHN which is a very reputable wheel maker, when i boutht my RSV told me fit them with 235/40/18!!! END OF STORY!!!!

 

[jase0851]

i thought when it comes to tyres 235= width 40= profile and 18=size of the wheel. the width has no bearing what so ever on the rolling diameter

 

[Issac Hunt]

The profile is a % measurement, width is in mm.

So as I understand it 225/40/18 must have a different(slightly) rolling radius from a 235/40/18.

 

[J7USS]

If you have 225/40 and a 235/40 on a for example 8J wheel, the 235 width will add a slight more depth to the wall.We're not talking loads but adds to the % rolling radius.
For example..225/40 on a 9J wide alloy will look lower profile than it would on a 8J because the tyre on the 9J has had to stretch out wider if you catch my drift..

 

[AndyMac]

40 is 40% of the width, so the width is critical when calculating the rolling radius

 

[ozique]

what about 245/40/18 on 8x18 wheels? too wide or should be ok?

 

[jase0851]

i think 245 might be to wide mate

 

[J7USS]

@ Ozique,Id say 245 are too wide...
Does your profile look Bigger than a 40??