jetsfan101

Whats going on guys,

Just recently bought a 2006 A8L quartz gray, wanted to say hello. So i am new to the A8 but not new to Audi. Last Audi i had was a 06 A6 3.2

Its basically bone stock right now and that's essentially how i will keep it with the exception of a few musts like tints, rims, fogs, etc.

I am looking at 20" A7 replicas to go along with 255-35-20. They are 9" wide with +40 offset so i think they will look nice by sticking out extra +11mm to the fenders. FYI right now i have OEM 18x8.5 +45 offset.

My question is, with the extra 5MM offset difference, do you think i will need to buy longer bolts or will my OEM bolts be long enough to safely hold the wheel in its place?

Also, has anybody had bad experiences with steering wheel vibrations on replica rims on the A8? I went through 2 sets of replicas on my A6 because no matter how well i road force balanced them i would get a slight steering wheel shake 55-65mph. Then i got a 19" set replica and made the guy send me the rims with print outs of the wheel balance results, and it was much better...

MP4.2+6.0

Welcome on board!

On wheel bolts, unless you run separate spacers, the wheel bolts should just stay the same. This assumes the replicas use the standard Audi ball type bolts (rather than cone shaped). Offsets by themselves have nothing to do with bolt lengths.

255's will make the wheels look a bit small in the wheel wells in 35 series if that matters. 275's in 9" are the factory size for 20's. You could look at 255/40's if you want to step the diameter up just a bit over the 275/35's. 265/35 is the S8 size as another flavor, though 265 tires tend to be pricer or have somewhat less selection than 275's; that is tire specific if you know what you want.

You could also avoid the replica quality issues if you look at Audi OE. Clean D3 wheels can be hard to find in the larger sizes, though D4 and their sister A7/S7 20's are all over eBay. You have to deal with the larger hub center on the newer Audi's (with a concentric ring) and possible TPMS sensor fitment issues (D4's don't use wheel sensor TPMS), but it's another way to skin the cat. IIRC, the D4 offsets also got a bit more aggressive.

jetsfan101

hmm interesting note on the 255-35-20 looking small in the wheel wells. I run 245-40-18 now and my tire diameter is 661mm. With the 255-35-20 my diameter will be 686mm. So theoretically my wheel gap should be eliminated by 1.25cm.

Does anyone have pictures of how 20s look with 255-35 tires?

Also, i dont know if this means anything, but tire rack recommends 255-35 but i think they try to match closest wheel diameter to oem

MP4.2+6.0

the OE fitment is unmistakably 275/35-20 in 9's on D3 A8's (either a "sport" wheel option on 4.2's or very common on W12's) and 265/35-20 on D3 S8's. Just find your tire pressure sticker and you can confirm--2006's still had the older style stickers listing the different sizes, which are often covered in the owner's manual. The D4's actually moved to a yet bigger diameter w/ 265/40's. And yes, I do expect better of TireRack, but far from the first time I've seen errors and bad info on their site, including specifically tires on a D3 for XL fitment.

On the "math" side, you will also find the speedo error greater (up to 5% per one published review) in the 27" diameter sizes typical of the 18's and 19's. 27" = approx. 685 mm. I don't know where you got the 245-40 18's from relative to a D3; 18 factory is 255/45 so it is both wider and taller (x2 since it is a bigger aspect ratio multiplied by a slightly greater width). Yes, you could run the 255's, but in 20's I would take both the greater sidewall height (which gets you almost back to the 19" sidewall) as well as a little more rim curbing protection for 9" wheels .

jetsfan101

copy. thanks


I'm still having a hard time finding some good A8 pics with 20s and their respective tires. Now i am particularly curious how the 20x9 et +35 sits. The search goes on...

MP4.2+6.0

I run 12/20 spacers front an rear on factory 20's at ET 46, so my effective net offsets on 9" wheels and 275's are 34 front and 26 back. That looks buttoned down; someone recently posted a few pics IIRC here on AW with the same set up if you try a search.

MP4.2+6.0

https://www.audiworld.com/articles/r...ports-package/

This featured an A8 where the primary mod was spacers if you read closely. As I recall he was running 255's and those are probably 19" wheels. In 255's relative to 275's, the net offsets get another step or two more aggressive to land at the same point with factory wheels. The spacers/offsets in these pic's would be on the aggressive side while still (just) avoiding rub or clearance issues.

jetsfan101

great information thanks. reason why i was so curious is because another set of rims caught my eye they are 20x9 et 35 and i was thinking they might stick out too far in the front. I guess they wont

Going back to what you said about how offset doesnt affect bolt length. I was under the impression that the stock bolts were made in length to correspond to the offset of the oem rim (by offset i mean the fatness of the center of the rim where the bolts are being screwed in. So i thought since the offset will be larger by 1cm, then the center of the rim would be fatter to make the rim stick out 1cm more. correct me where i am wrong please

MP4.2+6.0

You are thinking of it essentially like they would cast more metal into the wheel almost like a spacer to affect the offset. Instead, the dishing of the wheel is simply changed. That is, how far in or out the hub face is located relative to the centerline of the outer rim area where the tires mount up. For example, "deep dish" wheels have the hub center pushed way in with the effect of pulling the tire outward. Those are wheels around since the days of hot rods, modified Chevy's and Fords and such. Common with boat and other trailer wheels too since you want the wheels away from the frame. Yet other wheels have the hub center way far out where the hub and brake area are tucked way inside the wheel. Common on FWD, especially older ones.

A good example of the spectrum are the C5 variants where the wheel offsets moved around a lot (putting aside their interdependence w/ rim width). They were in the mid 40's on V6's, but then went to low to mid 30's when they flared the fenders for 4.2's, RS6's and S6's. Then they went down into the 20's with the all road and its add on plastic fenders. All of this was enabled by sheet metal (or plastic) changes to the fenders, and then they modified the offsets via the amount of "dish" they designed into the wheel.

Through this though the bolts are all the same. Thus I can bolt the OE C5 RS 6 wheels I have in 8 ½ x 18 and ET 30 either onto my C5 4.2 or onto my A8. Putting aside the fancier cone washers the A8 bolts use, I can interchange the wheels over to my A8 (and did once as a test fit). For that matter, I could use the lug bolts from either car. In fact, those wheels with a more aggressive offset look good on the A8, though they don't have the milling for the TPMS sensors.

jetsfan101

clear as day now. thanks. i turned off my tpms only issue remains getting rims that will sit well. I think i will get the 20x9 et 35.