Wheel dimensions

[bigbaz1974]

Alright guys,

Im looking at a set of Vossen CVT alloys for my car. I currently have the audi rotor type alloys 20". Can anyone tell me what the PCD, width and offset is for these wheels. I have 4 new tyres on my existing wheels so was gonna get the new alloys the same size to suit, thanks in advance

[Wilko]

http://www.wheel-size.com/size/audi/rs4/

[bigbaz1974]

Thanks Wilko

[BMW2RS4]

A word of caution; if the CVTs are 10.5" width, then the standard 265/30r20s will have a fair old stretch on those rims.

[Madelvic]

This will help you with offsets and rolling radius

http://www.carbibles.com/tyre_bible_pg4.html

[bigbaz1974]

Thanks for the help guys, going by wilkos link my wheels are 9 x 20 rims, 5 x 112 PCD with 26 offset(tyres 265/30/20).
Demon tweaks have the CVT'S same size so will be a straight swap for my tyres. Are there any advantage/disadvantage of going for wider rims say 10" or am I best sticking to 9" like I already have as standard??

[Wilko]

Might be worth getting in touch with Prestige Wheel Centre, site Sponsor on here, they've already done a B8 RS4 on CVT's for Vossen.

http://blog.vossenwheels.com/audi-b8-rs4-on-vossen-cvt/

[bigbaz1974]

Yeh have already messaged them Wilko thanks just waiting on a reply

[BMW2RS4]

The width will determine the depth of concavity. Not familiar with 10" but I suspect that the 9" will have a flat face with the 10.5" having a deep concavity. Eg. Audi r8 uses staggered fitment of 9" on front (to clear bbk) & 10.5" on rear. It is normal for RS4 owners to use square set up I.e. 10.5" on both axles.

Thanks for the help guys, going by wilkos link my wheels are 9 x 20 rims, 5 x 112 PCD with 26 offset(tyres 265/30/20).
Demon tweaks have the CVT'S same size so will be a straight swap for my tyres. Are there any advantage/disadvantage of going for wider rims say 10" or am I best sticking to 9" like I already have as standard??

[Madelvic]

Stating the obvious if you go for 10 inch rims instead of 9 then depending on the offset wheels will possibly go further into the arches and/or stick out further. You'd need to be certain they won't rub on bodywork so I'd strongly recommend you copy the fitment that somebody has tried and know that works. As mentioned above standard tyres might be too much of a stretch (and even less in the way of sidewall to protect the rims) and if you go for different size tyres then there is a whole new issue regarding rolling radius, speedo calibration etc

Some do, but for me I stick to the manufacturer spec. Also probably want to tell the insurance company what you've done to cover yourself

[bigbaz1974]

Thanks guys

[Revolution]

Would suggest a choice of 275's on 10" rims or 285's on 10.5" width

weve done both

hope that helps

[bigbaz1974]

would my current 265's fit the 10 " rims OK as they are new would save me getting another 4 new tyres. What about the 9" rims have you had anyone with them and is there a reason for going wider ?, thanks in advance

[BMW2RS4]

If you look at the R8 in the image below, you will see that the front wheel is a 20"x9" with a flat profile. I'm 99% sure that the 20"x10" has the same flat profile. The rear wheel is a 20"x10.5" with a deep concave profile.

The following image is of the Ferrada wheel design and demonstrates how concavity can be enhanced by using a wider rim.

So, in answer to your question, the reason for going from a 9" (or 10") rim to a 10.5" rim is to improve appearance by deepening the concavity.

Unfortunately, because you already have a set of tyres, you are attempting to chose your new rims based on whether these will fit; thus limiting your choice.

Having said that, the following RS4 is fitted with the 20" x 10.5" CVTs all round AND 265/30R20 tyres but, as I've mentioned previously, the tyres are a real stretch, have an exposed rim (i.e. offer zero protection against kerbing) and are not recommended from a safety point of view; they might even invalidate your insurance if your insurer is not notified in full and even then you run the risk of them not insuring your vehicle.

Hope this helps to make your decision

[bigbaz1974]

Thanks for the advice mate, some food for thought, maybe worth keeping my existing wheels and tyres as a set and going for wider tyres on the wider rims, got me thinking now