A8Lsport

I am looking to add some wheel spacers to the rear of my 2007 A8L. Something along the lines of H&R 8 or 12 mm to fill the wheel well out a little more without putting undo stress on the wheel bearings. This coupled with some 20x9 inch rims should make for a nice addition to the daily ride. Depending on the offset of the rims, I might need to use the spacers in the back to push the rims out a little more in order to gain a more desirable appearance.

1. Does anyone know the length of the standard lug bolts on the A8 and are they conical or ball seat in nature? 2. At what thickness do the H&R spacers have the hubcentric extension on them so the wheel mounts perfectly centered? Don't want any chance of vibrations. 3. Does anyone have any updated comments on the H&R wheel spacers and how they may make the car drive?

MP4.2+6.0

First, don't use 8 mm. I don't think you can get those hubcentric (with the shoulders to lock it all in place properly). 12mm is the thinnest you can get that will have the proper inside and outside diagonal insets and lips that make it hubcentric. The thinner ones effectively are just spacer plates and thus rely on the wheel bolts for centering--not the way to go... And even in the 12mm's, be careful--H&R sells one set with the proper Audi set up for hubcentric, and another different one that won't be optimum.

BUT, having BTDT, let me suggest you just bite the bullet and go to 20mm in the rear. If you do that with 20 x 9 Audi OEM (i.e. 46m rim offset) you will REALLY like it. I see your concerns about bearing loading, but consider that the bearing loading up front is really WAY higher than the back--all of the absolute axle weight, the way front heavy high cornering loads, and the heavier front unsprung weight (due to all of the larger calipers, rotors and outer CV joints). I also used to have similar concerns on my C5 4.2, which weighs about what the D3 4.2 does at just over 4,000 pounds. But then I realized Audi used 46ish mm wheel offsets on the 2.8/2.7T/3.0/3.2, 35mm on the 4.2, 30 mm on the RS6 and only 15-20mm on the allroad. Underneath though the hub and bearing hardware was the same, in the later years anyway. Said another way, on effectively the same bearing position, they were altering the offset by up to 25mm both rear AND front, which is logically similar to using up to a 25mm spacer if one otherwise started with a 45mm offset wheel and ending up at the allroad 20mm type offset.

Having done it live on my W12 and always with H&R parts, I can confirm in the 20 x 9 with 46mm offset, 20mm in the back and 12 mm in the front seems ideal visually and yield NO rubbing. 25mm rear and 15 mm front seems to be about the max, likely risking a bit rubbing in only extreme scenarios. But the look is just a bit too "pushed out" anyway (I tried it). At 20mm rear and 12mm front it really looks factory dialed in for a sport suspension type set up that also factors in the wheel width and look. Also, I think increasing the rear track width should cut down on the usual understeer/front push Audi's are known for; my guess is Audi cuts the rear track width down in part specifically to dial in more understeer for lowest common denominator drivers.

Last, Audi wheel bolts are always ball shaped where they meet the wheels. Buy the spacers from a reputable shop (on line or otherwise) and they will know the right length. The H&R catalog has the correct guidance in the footnotes; if you search online you can find it. If need be, I can backtrack to my order if you end up at 12mm or 20mm like I did.

P.S. For anyone reading this with Audi OEM 8 1/2" wheels (generally the 18" and 19" diameter ones), my prior calcs suggest you can add 5mm (i.e. roughly 1/2 of the 12.5mm decrease in rim width) to any spacer suggestion I note above and end up in about the same place relative to the fender lips. Said another way the 8 1/2" OEM rims end up deeper in the fender well to start when you look at the offset measurements.

A8Lsport

I am still trying to source the oem 20x9s and may have to change to the Mandrus Millenniums in order to find a 20x9, even those are on back order from one of the online dealers. I like your idea about using the spacers that were 12 front and 20 rear. I just measured the space from the outer tire to the inner fender on my car and came up with about 20mm of space in the front and about 30mm of space in the back. After adding your spacer widths that would leave 8mm in the front and 10mm in the rear for a more aggressive and balanced look. I was quoted three different offsets for the mandrus rims today that I believe were 42, 38, and 32 so that thickens the plot for possible combinations.

If I had the Mandrus rims with a 42 offset in the front that would push the rim out 3mm from the stock 19s. Then add another half of 12.5mm when going from an 8.5 to a 9 inch rim, which pushes the rim out by another 6mm, for a total of 9mm. This leaves a gap of 11mm (20-9) of space between the tire and the fender. With the same in the rear and a 12mm spacer, that would push the rim out 21mm (3+6+12) leaving a 9mm gap. That may not be as aggressive as your setup, but could work for me.

After that I need to buy a vagcom unit and lower the car a bit myself, or try to get the dealer to do it for the cost of the labor.....I am dreaming on the latter option here right.

MP4.2+6.0

if it helps. From having checked it, the first place rear rubbing will occur is apparently NOT the fender but rather the inner felt wheel liner. I got a floor jack directly under a rear tire and started compressing the suspension. The rub point is about 20 degrees toward the front of the car from vertical where the tire sidewall right near the tread would abrade the liner slightly. In my judgment the suspension compression where it occurred would be really extreme. It was still in the range of travel of the shock, but on the road it would likely a rim bending type extreme impact or a bottoming out to drive the suspension up like that. I found the condition with 25mm spacers on the Audi OEM 20 x 9's ET46 with 275/35's. Would not touch with the 20mm spacers no matter the range of travel. Never saw it get close to the actual fender edge when I went over it all.

One other reference point for my set up to give you some visual sense. If you take the vertical plane of the edge of the tire sidewall to construct an imaginary vertical line, that line intersects with the fender lip in the rear at the point about two thirds of the way forward on the gas filler lid. In other words, if I look down from above the gas filler lid at that point, I see the fender edge and the tire side wall all line up vertically. Since that is about the rear 1/4 or so of the wheel it all looks right to me; the top and leading edge of the wheel definitely fall inside the fenders as expected. Front is a visually similar mirror image. And, on the practical rain test, the water stays inside the fenders by an large and doesn't splash the side of the car in any way really noticeable above stock--and my car is black so I would see it. I get much more of that road splash actually on my C5 A6 4.2 with factory wheels and the factory flared fenders.

A8Lsport

Thanks again for all the great insight into adding 20 inch rims to the A8. Sadly I can't seem to find any 20x9 w12 oem rims to purchase, so I might have to go with the Mandrus Millenniums when they come in at the online store.

I was looking to get the Hankook ventus v12 evo k110 tires. They have great reviews on tirerack especially for a quite comfortable ride. Anyone have any feedback on these tires or have any ideas how to find any of the 9 spoke factory 20x9 w12 rims?

MP4.2+6.0

Why not the newer twin seven spokes ("new style" RS4) in 20's, which were also sold on many more 4.2's and some S8's too as an option. I have found those twin sevens on the market several times, while I agree the 9 spokers ("old style" RS4) are virtually unheard of, especially now after having gone away for some years.

The twin 7's weigh almost 5 pounds less per wheel than the 9 spokers--I have used both so know each one. Both versions are forged as well; the twin 7 shows the weight advantage from the forging while the 9 spoke really does not.

Where are you located BTW?

A8Lsport

The seven spoke rims just don't do it for me. I like a rim with a little more substance to it, but that is just me. The 9 spoke W12 rims are understated and classic, and I think look best in their 20 inch format on your car. The Mandrus Millenniums look real nice on AEinaD3's car for my tastes as well. The mirror cut rim edge makes them very sporty and aggressive. BTW I live in Dallas.

MTN

I just purchased some H&R spacers from ECSTuning per your recommendation in your post. In you post, you mentioned that Audi bolts are always conical. However, when I tried to order bolts to go with the spacers on the ECSTuning site, the site mentioned ball seat type bolts for Audi OEM wheels. I have purchased many parts from ECSTuning in the past and never had any issues. I would appreciate your confirmation on the bolt type. Use URL below.
http://www.ecstuning.com/Audi-D3_A8-...,_-and-_Nuts/2

Thanks.
MTN

MP4.2+6.0

Sorry I get those confused sometimes since they both have an overall taper to them. But yes, Audi's are always ball shaped (rounded rather than a straight angle cut) and have been like almost forever.

I edited the old post for this. Thanks for catching it.

MTN

Thanks.