definitive tire, wheel, and offset thread

[ttboost]

I know a 19x9 with ET29 fits perfect with 275/30-19. ET (offset) is how much it sticks in or out. If a wheel is taller, it usually has to have a smaller offset (this will push it out), to mitigate rubbing on the inside, BUT you also have to contend with the outside rubbing. Tire size helps this. But can also give you a crappy ride if you have to go to such a low profile to avoid rubbing. Spend some time on Tirerack's site, you will learn all you need to know. There are also plenty of threads where people say what they are running. Most are extreme and have had to roll the fenders. I was not willing to do this.

[Other_Erik]

To quote a previous poster on this topic: "I searched high and low. On this forum and others. I found anecdotal information for specifc wheels. I used calculators, but they just confuse me. Either I am blind or slow (likely both), but I cannot find" info on the setup I am looking into running: OEM Audi Speedline 19" Peeler wheels. I know these come in a variety of flavors from various Audi oem models. The set I am currently looking at is off a 2011 S4 with TPMS sensors.Would the peelers off an S4 or S5 be the best to put on RS6?
Not sure how many widths Audi made these in, think 8.5" and 9" are both available & no idea which is a better option for the RS6?
Also not sure which offsets on these wheels would be compatible with the RS6 without spacers? If spacers are necessary what size? Also as other Erik suggested above, think I'd need to adapt the hub from 57.1mm to 66.6mm. If anyone can educate me on this would be very helpful to know before I move forward and buy the wheels want to make sure they fit!! Thanks in advance

Need part numbers or at the very least the actual wheel dimensions for the peelers you're looking at. Depending on which (S4/S5/etc) 19x8.5 or 19x9, there are different offsets for different models.

I've been using http://www.willtheyfit.com to gauge roughly what is needed.
For me to go from stockers to the peelers I had from a 2011 S5 Prestige, measurements went like so:
Original: 255/40/18 on 18x8 ET35
New: 255/35/19 on 19x8.5 ET32
Difference: -3.2mm means a 5mm spacer is more than enough to clear, and ends up in total pushing the edge of the rim outboard about 1/3 of an inch.

Interestingly enough, going on those same lines for the rear, I'm looking at some 11" wide wheels to run 305's in the rear for a foot of rubber on the road.
Original: 255/40/18 on 18x8 ET35
New: 305/25/20 on 20x11 ET25
Difference: -28.1mm means a 30mm spacer brings me far enough to clear, and ends up in total pushing the edge of the rear rim outboard just a hair over 3 inches. Based on how the car sits now, that means I'll have ~1.75" of wheel sticking out compared to the top of the fender arch, or ~2.5" beyond the middle of the fender arch. That's going to look f'in MEAN!

[ttboost]

....and to add to my post above (and Other_Erik's too), before I sold my RS6, I tried the 20" BBS wheels off my Benz just to see what they looked like and if they fit. Well, well well....they fit, but much like above they stuck our about an inch or so, but looked killer. Front fit fine too. Didn't drive anywhere as I only tried one side (front and back), but it's likely they MIGHT rub a smidge, but maybe not with some fender rolling. The BBS CH-R's are 20x10.5R (305/25-20) and 20x9F (255/30-20). Both front and rear are ET25. I will try to find some pics. These BBS wheels are for sale too. You will need hubcentric spacers for them to fit. Although Audi and Benz have the same bolt pattern (5x112) Audi hub is 57.1 and Benz is 66.56. I obviously have the hubcentric spacers too.

[nistah]

Need part numbers or at the very least the actual wheel dimensions for the peelers you're looking at. Depending on which (S4/S5/etc) 19x8.5 or 19x9, there are different offsets for different models.

Thanks Erik! I found out that they are 19X8.5 5X112 bolt pattern with 43MM offset. With this info can anyone advise what would need to be done to make these peelers fit the beast properly?Thanks in advance!~

[Other_Erik]

Thanks Erik! I found out that they are 19X8.5 5X112 bolt pattern with 43MM offset. With this info can anyone advise what would need to be done to make these peelers fit the beast properly?Thanks in advance!~

Thanks to the high offset, you would need to add spacers to keep the inner edge of the tire away from your strut.

Based on the wheel dimensions, the inner edge will be ~17.4mm closer to the suspension strut than your original wheels/tires, and the outer edge will be ~4.7mm further inward.

You will need to adapt the hub bore from the 57.1mm hub on the RS6 to the 66.56mm bore on the wheel.

You'll be in need of the following:
4x57.1->66.56mm hub bore adapters, 5x112 bolt pattern
4x20mm 5x112 bolt pattern spacers

They'll need to be in this sandwich order:
Wheel -> Adapter -> Spacer -> Hub

When you're finished with this, your wheels will stick out just about 5/8 of an inch further than the stock wheels (-4.7mm + 20mm = +15.3mm)

Good luck, hope they look as good on the car as painted stockers, I got my fair share of compliments on the meteor black 18's that I used for my winter setup

O_E

[Greyyork]

So I've read through every single post and all the information I could find and I'm still slightly confused. I have a set of 18x9 Formula HLT OZ rims ET 35 that I'm going to be putting back on soon. The old tire I was running was Conts 255/40/18. Now I'm going to buy Summer Pilot Super Sport and I'm wondering what size I should go with. It's all confusing to me. Mainly I want to make the sidewalls smaller so I should go with 35 right? Will that fit? Only other question is if I go 265 or even 275 what affect does that have on appearance? Thanks.

Grey

[Other_Erik]

So I've read through every single post and all the information I could find and I'm still slightly confused. I have a set of 18x9 Formula HLT OZ rims ET 35 that I'm going to be putting back on soon. The old tire I was running was Conts 255/40/18. Now I'm going to buy Summer Pilot Super Sport and I'm wondering what size I should go with. It's all confusing to me. Mainly I want to make the sidewalls smaller so I should go with 35 right? Will that fit? Only other question is if I go 265 or even 275 what affect does that have on appearance? Thanks.

Grey

If I were you, I'd stick with stock size. 255/40-18 is the proper size to keep the speedometer and odometer dead-on accurate.

Keeping the speedo/odo accurate on the same diameter rims, you will always have the same size sidewall. If you want a shorter sidewall (warning: also means rougher ride), you have two (possibly three) choices:
1) Up-size the Rim Diameter (19's, 20's, etc...) and match the new tire to the new wheels
2) Use a reluctor setup to change the revolutions per mile appropriately
a) your example, going to 255/35-18 - you are changing the total rolling diameter from 2077.2mm to 1997.1mm - this means you will have more revolutions per mile.
the math: 1609344 mm/mile - stock setup 1609344/2077.2= 774.76 revolutions per mile - new setup 1609344/1997.1=805.84 revs per mile, leaving you ~4% off speedo and odo.
3) Not sure if this one is possible, but if there is a coding option from a Ross-Tech to change recognized revs per mile, you could do that...

Wider tires: The proper fitment for wider tires on an 18" rim follows:
255/40-18 - Stock 10" wide, 2077.2mm circumference - Speedo set +/- 0.00%
285/35-18 - 11.25" wide, 2063.1mm circumference - Speedo error +0.69%
295/35-18 - 11.66" wide, 2085.1mm circumference - Speedo error -0.38%
I definitely wouldn't recommend going any wider on a 9" rim. If you are lucky enough to find 18x10-11 inch wheels,
335/30-18 - 13.2" wide, 2067.8mm circumference - Speedo error +0.46%
345/30-18 - 13.6" wide, 2086.6mm circumference - Speedo error -0.45%


Regardless all the above, 2 points to make:
1) 18x9" ET35 rims brings the inner lip of the tire 15.7mm closer to the strut. Add 15mm spacer, and if you need, hub bore adapter if the rims are not 57.1mm bore, and you're good to go
2) If you want wider tires, I'd recommend only doing so on the rear. The front is already very tight clearance between tires and bits you don't want the tires to scuff.


Whew, this post got long in a hurry

TL;DR - Stick to stock width in the front, they only get 30-40% of the power anyway. Wider is better in the rear, but your tires are going to poke out beyond the fenders. Stay as close to stock circumference as you possibly can.

[ttboost]

While it's certainly easier to have someone else do the math for you, it would be beneficial to learn this info. Tire rack has a ton of info to help educate. http://www.tirerack.com/about/techcenter.jsp Scroll down to "Wheel tech".

I will try to help you this way, with regard to your old tires. 255 is the width of the tire in millimeters. 40 is the sidewall dimension, which is a percentage of the width. (40% of 255 is 102mm, so the tire is 102mm tall from the rim to the tire tread). 18 is obviously the rim diameter, or the inner diameter of the tire. ET (or offset as it is often called) is the distance from the center of the wheel to the face of the mounting surface. ET changes things dramatically, but can also be very forgiving. All else being equal, the smaller this number, the further the wheel sticks out, the bigger the ET, the more it protrudes inward. Obviously, different size tires exaggerate this effect. I think ET dimensions change with different wheels and different wheel manufacturers.
To answer your question, going from a 255/40 to a 255/35 will give you a 13mm smaller sidewall, which you seem to want. The ride will be much firmer, also potentially subjecting your wheels to damage from road conditions, as a thicker sidewall acts as insulation. It will look better, but at what cost? Going to a 265 or 275 will make it a little better as we said above, percentage of a bigger tire is a bigger sidewall. ET problems are fixed with spacers, rolling fenders and different tire sizes accordingly. RS6 factory wheel offset is 30. All wheels have their dimensions cast on the inside including diameter, width and ET. Hope you don't take this the wrong way, just trying to help.

[Greyyork]

This is why all other car forums pale in comparison to RS6.com. The amount of detail in explanations and help is absolutely amazing. Thanks guys, I'm going to be sticking with the 255/40. Only other thing that confuses me is I'm trying to buy the Pilot Super Sports off the local base PX and I know I have rotational tires, but I don't see an option when filling out the forums for tires for a "rotational" tire. Any side thoughts before I drop the 1200 on these bad boys?

[hahnmgh63]

I found the Pilot Super Sports at Costco out the door with tax for only $1100 up here in WA, that includes our 8.8% sales tax so you should be able to find them at Costco in San Antonio for less. You at Randolph or Lackland?
OOPs, after re-reading I guess you may still be in Germany, I forgot.

[Greyyork]

Yep still in Germany, and if you guys didn't know http://www.discountedwheelwarehouse.com $213 a piece. You can thank me later.

[Other_Erik]

This is why all other car forums pale in comparison to RS6.com. The amount of detail in explanations and help is absolutely amazing. Thanks guys, I'm going to be sticking with the 255/40. Only other thing that confuses me is I'm trying to buy the Pilot Super Sports off the local base PX and I know I have rotational tires, but I don't see an option when filling out the forums for tires for a "rotational" tire. Any side thoughts before I drop the 1200 on these bad boys?

I'll take it as a compliment, I know I tend to ramble when I get into the tech side of things...

Did you mean directional rather than rotational? The only time that matters is when you're getting a rotation done. With some cars, you rotate Front/Rear as well as Left/Right. With Directional tires, you ONLY rotate Front/Rear. Even with non-directional tires (PSS as an example), I still recommend only rotating front/rear on any vehicle due to the way the steel supports tend to sag after a few Left/Right rotations. As always, pay attention to how your tires are wearing before you try and diagnose any other problem related to road/suspension noise - You'd be surprised how easy it is to spot feathering on the lip of the sidewall, or heavier wear to the interior of the tire, and from there be able to say EXACTLY what could be wrong with your suspension...

Not sure about your pricing since you're in Ansbach (you lucky bastard you!), but it seems PSS is the go-to standard around here. I can get a set with road hazard from Tirerack shipped (not installed) for $1116.88 But if discountedwheelwarehouse can beat that price, I'm all over it

Good luck!

O_E

[nistah]

Thanks to the high offset, you would need to add spacers to keep the inner edge of the tire away from your strut.

Based on the wheel dimensions, the inner edge will be ~17.4mm closer to the suspension strut than your original wheels/tires, and the outer edge will be ~4.7mm further inward.

You will need to adapt the hub bore from the 57.1mm hub on the RS6 to the 66.56mm bore on the wheel.

You'll be in need of the following:
4x57.1->66.56mm hub bore adapters, 5x112 bolt pattern
4x20mm 5x112 bolt pattern spacers

They'll need to be in this sandwich order:
Wheel -> Adapter -> Spacer -> Hub

When you're finished with this, your wheels will stick out just about 5/8 of an inch further than the stock wheels (-4.7mm + 20mm = +15.3mm)

Good luck, hope they look as good on the car as painted stockers, I got my fair share of compliments on the meteor black 18's that I used for my winter setup

O_E

Thank you O_E will keep you posted on how everything works out!!!

[2000c43]

I apologize if this has been answered elsewhere, but I have not found the exact answer. I have an RS6 with stock oem 18" wheels and tires and factory ride height. I would like to purchase ECS Tuning spacers and don't know how big of a spacer would work without rubbing on the front. I think that kismetcapitan's RS6 looks great. I know he is running 10mm spacers front and rear, but he has lowering springs and therefore needed to roll the front fender lip and cut the plastic liner to avoid rubbing. If I do not have a lowered ride height and do not want to roll the fenders, what would be the maximum spacer with the stock 18" wheels and tires? I feel like 10mm front and 10mm back would work with a factory ride height and factory wheels and tires, but I am not sure. ECS spacers come in 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, and 15mm increments.

[nistah]

Thanks to the high offset, you would need to add spacers to keep the inner edge of the tire away from your strut.

Based on the wheel dimensions, the inner edge will be ~17.4mm closer to the suspension strut than your original wheels/tires, and the outer edge will be ~4.7mm further inward.

You will need to adapt the hub bore from the 57.1mm hub on the RS6 to the 66.56mm bore on the wheel.

You'll be in need of the following:
4x57.1->66.56mm hub bore adapters, 5x112 bolt pattern
4x20mm 5x112 bolt pattern spacers

They'll need to be in this sandwich order:
Wheel -> Adapter -> Spacer -> Hub

When you're finished with this, your wheels will stick out just about 5/8 of an inch further than the stock wheels (-4.7mm + 20mm = +15.3mm)

Good luck, hope they look as good on the car as painted stockers, I got my fair share of compliments on the meteor black 18's that I used for my winter setup

O_E

Erik I pulled the trigger on the set of slicers described above. I understand that I will need 4x57.1->66.56mm hub bore adapters, 5x112 bolt pattern however not clear on the 4x20mm 5x112 bolt pattern spacers they seem to have spacers for both the 57.1 & 66.5 hub bore wheels since I am adapting to 66.56 I suspect I need the first ones listed below

20mm Hubcentric Wheel Spacer Kit Fit Audi A5/S5 2009-2012 Bolt Pattern: 5x112 Center Bore: 66.5 Thread Type...


20mm 5x112 Hubcentric Wheel Spacers for Audi A4 A3 A6 VW Jetta Golf GTI (57.1 Bore)

However not sure, please confirm so I can idiot proof my plan before ordering. Thanks again for your knowledge and help on this topic!

[Corbett]

If you are using hub rings then you need 57.1 spacers

[bmlee007]

Finally got my delivery from tire rack. OZ Leggera HLT 19x8.5 et 38 (w/10mm spacer for final et28) wrapped with Michelin Pilot SuperSport 255/35/19. IIRC, I had to select the 2010 S6 to find them on the site, then a few emails with Gill to get everything set up. Previous setup was RS4 reps, 18x8 et38 w/20mm spacer, so these are tucked slightly back under the fender.

[G2]

It's a long thread,just throwing out my latest tire dilemma: Input is welcomed.

Despite my initial excitement on the new RE11's (275/30-19), and fantastic traction, if not nearly amazing, another change seems needed. Not thrilled with flat spotting when parked. It's far worse than the S04's. Tried various tire pressures.
-- Thinking of switching back to Michelin.

But what size and load index, if that matters in the real world in terms of ride quality? Intended use is just summer and prefer the 30 series handling and slightly wider contact than 35's offer.

Anyone here with PSS's in 275/30? Really curious how the ride quality, but most importantly it's resistance to flat spotting is. Tire kid at America's Tire said they wouldn't sell this size due to low load index. Not worried....the 96XL rating should be fine, and is what the RE11's are.

But the 35's have a much higher load rating. Wondering if it makes a noticeable difference, or in helping to keep the tire round-- in the Michelin brand? Waiting 2-7 miles for tires (RE11's or S04's) to warm up, round out, smooth out, is driving me batty on the 16 mile daily commute. And it's not good on the suspension....

Considering (19"):
265/35 (easy fit, higher load, reduced contact patch)
275/35 (high load, tight fit, may need to raise front end)
275/30 ("preferred") slightly under OD helps clearance, increases WHP, widest tire.

Michelin seems like a "big" tire based on my AS3's. Bigger than Bridgestone for a given size? May be a factor?

Running OE wheels and Michelin AS3's until the dilemma is sorted. Rides like butter and handles OK for the KW3's.

What to do? Anything else I should consider?