B9 RS5 20" wheel offsets

[Baron.vB]

Hi everyone,

Seeking some guidance. I currently have the 20" stock wheels on my 2018 RS5. I understand these are an ET26, and fit a tyre 275/35 ZR20. The wheels look OK, but I have my heart set on some Vossen HF-2 or HF-5's - or similar styles.

Where I'm lost is on the offset. What I want is for the wheels be more outwards from the centre of the car, ideally 12-15mm. My understanding of offsets is that, assuming the wheel is the same width, that the offset becomes less. E.G I'd be looking for something that is between ET16 (10mm further out) to ET11 (15mm further out) if its the same width as the stock 20"s. Finding this offset is proving challenging.

So that makes me think I'm supposed to go wider like a 10.5" and run 285/30R20 tyres and use the extra width of the tyre. But then the offerings of offsets is still a challenge.

Can someone help educate me on this? I'm clearly not understanding something here or am I just looking at the wrong manufacturer of wheels. What have others done?

Cheers
Andrew

[MN_Pugsley]

I have the 2019 RS5, which came with the same size wheel set up as yours. I installed the Avant Garde M632's size 20x9 with a +20 offset. Stock 275/30 tires. No spacers. It's not quite flush but did push the face of the tire a little further out. They have various size set ups but I dont know if they are all the same ET/offset.

Link to the wheels: https://www.avantgardewheels.com/ag-...m632/#thewheel

[Smac770]

Offset has nothing to do with the width of the wheel per se. Offset is simply the difference in position of the center plane of the wheel width vs the mounting plane of the wheel hub. So 0et means the wheel hub face will mount right at the middle of the wheel. +20et means the mounting face is 20mm outward from the center of the wheel. Ie, the wheel is shifted inward 20mm. -20et means the mounting face is 20mm inward from the center plane of the wheel width, and so the wheel is effectively shifted outward 20mm.

So if you want the wheel shifted outward X mm, you want an offset that is X mm less than your current (be it +20-X or -20-X, whatever your original is).

But if you're also changing the wheel width, then it's more complicated. The same offset with two different wheel widths will have the wheel center plane at the same place relative to the wheel hub face, but the wider wheel will of course have the outside and inside faces of the wheel further outward and inward than the narrower wheel.

Of course, you could always run a spacer to adjust the effective offset as well.

[Baron.vB]

Thanks Pugsley and Smac. That is very helpful a particularly the note about the width change which I’m realising now would be undesirable as it complicates everything.

I have sent out a few enquirers with some wheel suppliers. Ultimately when I make my decision, I’ll be sure to share here. I want something that looks interesting and less “clinical” than the stock wheels.

In regards to wheel spacers, this was going to be my initial approach. However it turns out that where I live (Queensland, Australia) they are illegal and could even void insurance. The insurance matter is not a risk I’m willing to take.

Thanks! Andrew

[Smac770]

That's why calculators. Take your stock vs 285/30r20 on 20x10.0 et26 example:

https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm

The suspension and fenders rows, comments for wheel 2, is where you're looking.

With the same offset, the wheel is 1" wider, so the outside lip of the wheel will be 1/2" (12.5mm) more outward. But the tire is only 10mm wider, so the tire face will be 5mm more outward. If you want that tire face 12mm more outward overall, you'd combine the 285 with 7mm less offset. So 285/30r20 on 20x10.0 et19.

Whether or not all that outward shifting fits on the car, I have no idea.

[VVG]

Hi everyone,

Seeking some guidance. I currently have the 20" stock wheels on my 2018 RS5. I understand these are an ET26, and fit a tyre 275/35 ZR20. The wheels look OK, but I have my heart set on some Vossen HF-2 or HF-5's - or similar styles.

Where I'm lost is on the offset. What I want is for the wheels be more outwards from the centre of the car, ideally 12-15mm. My understanding of offsets is that, assuming the wheel is the same width, that the offset becomes less. E.G I'd be looking for something that is between ET16 (10mm further out) to ET11 (15mm further out) if its the same width as the stock 20"s. Finding this offset is proving challenging.

So that makes me think I'm supposed to go wider like a 10.5" and run 285/30R20 tyres and use the extra width of the tyre. But then the offerings of offsets is still a challenge.

Can someone help educate me on this? I'm clearly not understanding something here or am I just looking at the wrong manufacturer of wheels. What have others done?

Cheers
Andrew

Go to wheel-size.com and use their tire calculator. A fantastic tool and you can play with all sorts of numbers
http://www.wheel-size.com

[coolwater]

I’ve done two setups. Even though the 10.5 et22 is pushed out more the slight tire stretch on 10.5 vs 10 cancelled it out a bit. Lowered on HR VTF 3/4 inch.

20x10 et25 with 285/30







20x10.5 et22 with same 285/30








-cW


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[Baron.vB]

Ok this has been incredible. I feel like I have the right info now. Thanks for those photos as well.

The Vossen vendor in Australia have offered me 20 x 10.5 ET25 in the HF-2 style in Satin Bronze. The offset makes it 3mm more "inwards" than your second set of photos coolwater, which I think is going to be fine. I have however asked the vendor to double check directly with Vossen in Florida before I pull the trigger on a purchase order., as they aren't cheap. Overall I think they'll fill out the arches a bit more; while being cosmetically more what I like.

[Smac770]

Just know with /30 tires, at least according to Michelin's PS4S specs, x10.5 is at the max width for a 285/30r20 (9.5-10.5) and is outside the supported width for 275/30r20 (9.0-10.0). I think you were looking to go 285/30 anyway, but pointing this out so you're keeping this aspect in mind.

[Zombie5150]

I just got a set of Vossen HF-3’s with Michelin 285/30ZR/20’s. Wheels specs are 20 x 10 ET20. Big THANKS to Ben/Mops. I think the tires look perfect on the wheels. Certainly not stretched out and nearly flush with the rim.

[workerONE]

Is there any benefit to going with a more conservative offset and then using spacers as needed or should I just go straight to 9.5" wheel with ET16? Not lowered, stock suspension with Dynamic Ride Control.

[Smac770]

No spacer would be better. But maybe the wheel you want isn't in a best fit offset. They're just tools to be used as needed. But better to not need them.

[workerONE]

Thanks

[Baron.vB]

Pulled the trigger with Vossen. They were amazing and answered all my questions re: fitment.

The new wheels will be a 20x10.5 et25. This fills out the wheel arches an extra 7mm from the stock to wheels. They have warranted no scrubbing and provided me some commentary on my options on lowering the car a smudge with these.

I’m resigned to the fact that I’ll be up for rubber on all corners to get the 285 width. I’m ok with that.

Wheels are a custom order as I’ve gone for Satin Bronze HF-2s, and will take 10 weeks to get from where they are being made in Florida to me in Australia.

Excited and thankful for your help!

[Smac770]

You know you're on the hook for pics once it's all done, right?

[ninjamanRS5]

I know one of the main sales folks for Avant Garde and Vossen if you want a good point of contact. Just DM me and I'll send you their info. AG hooked it up with my SRX-01 forged monoblocks!

[Baron.vB]

You know you're on the hook for pics once it's all done, right?

Absolutely!

[Audi_Gummy]

Here is 21 x 10 et30 BC rz05 with 15mm spacers all around

[Baron.vB]

Hi all!
As promised, photos of the end product. Fitment of these is very nice indeed. I couldn’t be happier

For anyone researching in future these are Vossen HF2, 20 inch, 10.5 wide and ET25. Rears are Super Deep concavity and fronts are Deep concavity.

I wrapped them in Bridgestone Potenza Sport 285 30 r20


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