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Discussion Starter · #1 · (Edited)
Hello, I'm looking at various track wheel and tire options and alternatives. I've got a 2008 US Spec car, so it comes with 19" wheels standard. I believe in Europe, the "standard" wheel is an 18", with 19's optional.

If I am going to take the R8 to HPD events other than rarely and occasionally, I'd prefer to have a set of designated tires & wheels for track use, so .... I'm trying to put together information on the stock wheels and tires and weigh the pros and cons of various options:

1st, Wheel Weight ~ all things being equal, a lighter wheel & tire package would be preferred. FWIW, I partly to satisfy my curiosity has to how the stock equipment has handled things so far (@ 2 "mild" track days, & @ 3,000 miles of driving) I had the original stock pads changed out. I asked the service tech to weigh the wheels & tires as they came off the car, to get a rough idea of stock weights. Using a digital bath room scale (purported by the scale manufacture to be accurate within ± ½ pound, I came up with Fronts: @ 40.6 & 42.6 lbs for the two front tires (the left is worn a bit more than the right, but I kind of doubt it's as much as a 1.8 lb difference) OEM Tire/Wheel 235/35x19 Pirrelli P-Zero RO1 (Audi spec); and Rears: 57.2 & 56.4 lbs each, with 295/30x19 (100 Y) RO1 Pirrelli P-Zeros mounted. Averaging the weights, and using TireRack's data sheet for the Pirelli tires, 22 lbs for the 235's, 29 lbs for the 295's I come up with an estimate @ 19.4 lbs for the front 19x8½ rims, and @ 27.8 lbs for the rear per 19x11"

If anyone has any better rim weights for the OEM wheels, please feel free to correct, or add to these guesstimates on wheel weights.

The US dealer thinks the 19" OEM wheels forged, but doesn't know for sure. The Dealer parts guy is less certain of the 18" rim provenance. IME Audi has had a reputation for putting strong wheels on their "performance" (RS etc.) level cars, but I've really no idea what, if any manufacturing, i.e. forged vs. cast, difference there might between the 18 vs. 19" wheels. Again, if any one has any insight, I'm interested in the information.

As for the 18" OEM wheels, my dealership tells me as of June '08, there were none in the US. 18's would have to be special ordered from Germany, and .... well the parts guy has stories about how difficult it can be for him to predict how long such an order might take ~ wheels could come in as soon as a week, or he has apparently seen it take months for a "non standard" (for the US market at least) part to make it here. The dealership does't have any technical information on the OEM 18"s other than the part numbers and a price.

FWIW, as best I can determine, the 18's actually come in 3 wheels, one front, 18x8.5" ET42, and two different rears 18x10.5s. One rear is offset ET50, the other ET55. The ET55 offset is designated as part of a "winter tire" set.

The same winter/summer rear offset choice is also available in the 19" rims, with a slight variation. The summer 19"x11" ET50; the winter 19" is a listed as a 10½" wide, ET55 wheel.

In any event, so far as I can determine for US cars, all wheels use PN#420-601-025. Variations are controlled by the "{no letter}" or "a", "b" etc. US PN# and MSRP prices quoted are:

TireRack OZ Dymag
SuperLeggera Galileo Botticelli CarbonFiber
III III III & (?) Magnisum
~ 8.5 x18 ET42 front $743
A 10.5 x18 ET50 rear $743
D 10.5 x18 ET55 rear $743 ~ winter

B 8.5 x19 ET42 Front $964 estim 19 to 19½ lbs** 27.0 lbs 30.6 lbs 30.0 lbs @ 16lbs in 19X9" ET38
C 11.0 x19 ET50 rear $964 estim 27 to 28 lbs 29.0 lbs 31.2 lbs 33.0 lbs @ 19lbs in 19x11" ET40
E 10.5 x19 ET55 rear $805 ~ winter

** Note: I'd have to say this weight for the fronts is suspect. A quick look over front 8½x19 OZ rims on the TireRack site ranges from 27# for the Superleggera to 30.6# on the Galileo rims. Further, I've been given a Dymag weight estimate of 16lbs front for 19x9" rims and 19lbs rear for 19x11" Dymags have to be some of the very lightest wheel options out there. I have to doubt my own math that would put the Audi OEM front rims within 3 lbs of the Dymag pieces. I need to get the tires off the rims, and get the rims alone weighed on a good scale. If anyone's already gone through the trouble of doing that, please share. I can offer that on my Porsche Cayman, running lighter 18" BBS wheels over the stock Porsche OEM 19" IMO makes a noticeable handling difference. Personally, FWIW, I like the feel of the 18" wheel and tire set up better on the Porsche. I think the suspension w/PASM seems to stick better with the lighter tires & wheels.

I'd be interested if any one has any weights for the 18" tires &/or wheels; or other weights for other wheel alternatives.

In addition to the above, if one wants to keep the TPMS system, I'm told each wheel needs, at a minimum, a separate special TPMS bolt, PN#4D0-601-365 @ $15.53 each; and a TPMS sensor, PN#4FO-907-275-B @ $104 each.

I'm interested in what other tire and wheel combinations other R8 owners are using or considering for spare tire/wheel packages. I'm more interested in the performance aspect of the tire/wheel choices than the 20+" bling~bling stuff.

With 18" rims, it looks like I could run something like Toyo 888's in 245/40x18 front and either 275/35x18 or, I have a pair of 305/35x18s, but 305 may be pushing the recomended widths on a 10.5" rear rim.

I believe the 18"s would also provide more flexability with respect to choices of a good set of winter ice tires if one decided to use the car for winter events.

Cheers ` mike
 

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MichaelP, welcome. I think b888 in Australia, and myself in the USA, are the only two R8 owners that I know of who regularly track our cars. ( I would love to hear from any others out there! )

I have been running Toyo Proxes R888's 235/35R19 and 305/30R19 with great success on the OEM wheels. I wish the Nitto NT01 also came in these sizes as I have heard such wonderful things about it. But I'm very happy with the Toyo R888. I have added about 1.5 degrees of negative camber to the suspension. I am awaiting my order for H&R competition springs.

It is also my understanding that the OEM R8 wheels are indeed forged and are excellent track wheels. As you probably know, the R8 's oversized brake calipers make the R8 difficult to size correctly with other after-market wheels. Wheels rarely will fit over these large brakes. Also the scarcity of the R8, makes it difficult for wheel companies to design wheels to fit.

I'm trying to get Forgeline to make me some of their 18" ZXR3 competition wheels for my R8. There are considerably more track tire choices available in 18" wheels.

I wish you the best of luck. And please keep us advised as to your own track discoveries with your R8.
http://www.forgeline.com/products/competition-series/zx3r.html




Nitto NT-01

Toyo R888
 

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I'm a track rat and will be heavily tracking mine when I get it. It's been built, now waiting it to be shipped across the pond. I did VIR and Road Atlanta recently with some local clubs that I instruct for.

I really like Hoosier track tires, they have incredible grip, so I'll be getting those. Hoosier offers them in the stock R8 sizes. I'm thinking about getting O.Z.'s as a 2nd set of wheels. Not sure which I'll put the track tires on - the O.Z.'s are lighter weight but it seems a waste to buy flashy wheels like that for track use only.

I've been working with CarboTech here in the USA to produce brake pads for the R8. Very close to getting it done now, they will be able to do it soon.

mt
 

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Discussion Starter · #4 · (Edited)
Bohdii ~ FWIW, the shop I use was in touch with Forgeline about building a set of wheels for the car back in February/March of this year after I got an order slot in January. At the time, I was told by the mechanic I delt with that he thought Forgeline could/would do a set of 18" wheels ~ but ... apparently there was a bit of a communication gap.

When it came time to try to order, I was told Forgeline had recently confirmed fitment of 19's to a car, but apparently wasn't comfortable that their 18s would properly clear the brake calipers.

I don't know if Forgeline would be willing to take a 2nd look at the issue if they had a car in hand to check 18" fitment & measurements or not. Since 18" wheels seem to be the OEM size for Europe, with 19" rims optional, I don't think the issue is one of rim diameter, but rather the close proximity of the caliper to the rim spokes as one approaches the center of the wheel hub.

In any event, as folks find more wheel options I hope they'll take the time to post what they've found vis-a-vis choice, wheel weights and costs and alterantives. I know here in the US, TireRack lists 3 different types of OZ wheels for the car, all in 19" diameter.

Does anyone know if RS4 wheel fitments are a viable alternative?

Looks like you had your car out to Miller at the Audi Club event in March. I hear there were several other R8's there. I had another "pressing" obligation at Sears Point that week, and opted not to go. Based on the weather reports for that week for travel from Colorado to SLC, that was probably a wise choice on my part :) It would have been a bear trying to get either of my other HPDE car alternatives over the Divide on performance tires to Miller. FWIW, there are also probably considerably more winter performance tire choices available in 18's if you're brave, or foolish enough to decide to take on the Steamboat winter driving track with the car :)

Cheers, Mike
 

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MichaelP, yes, right now my R8 is pretty much living at Miller Motorsport. Actually it's had Toyo R888's as its only tires for a couple of months now. My R8 has seen more than 15 full track days since May 1. I keep it at a place near the SLC airport which is only 10-15 min from Miller Motorsport.

I also have a 485HP TPC Turbo Porsche Cayman S as well. In two weeks that car will being going to SLC to replace the R8 as my regular track car. And then the R8 will get some more PZero's again.

Thnx for the Forgeline info. The 19" R888's are really great tires, so I can probably live happily without the 18" tire options. I will probably just go with the 19" Forgeline wheels.

As to RS4 wheels, I would think that some spacers can provide enough clearance with the R8 brakes, as long as the wheels have the 5-112 Audi bolt pattern. Just find the right size of spacer for that particular wheel I guess?

hey did you do any of those Audi R8 test drives at Infineon? I'm wondering just how fast they let people go in those R8's at Sears Pt.
 

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Bodhii,

I can't imagine you would get much value from the Audi Sports Experience in R8's at Infineon in Sonoma. My wife and I are going in August and I have spoken with both the R8 instructors and it is a follow the leader (instructor lead) format. The strange twist on their driving school is that you share a car with another driver (switch off) which I am not a huge fan of unless I know the other person in the car with me.

You would need the Andretti/Gordon racing school or some other racing school for up and coming race car drivers versus a follow the leader driver school. The manufacturer schools (Audi/Mercedes) don't allow or even teach passing techniques at their events in the U.S.

If you and I are at the same driving event then one of us is in the wrong place. I have only tracked a couple times and the instructors said the course was for folks like me.

I will be heading out to Miller track in July after my miles are high enough on the car.

Cheers.
 

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Discussion Starter · #7 · (Edited)
.....
hey did you do any of those Audi R8 test drives at Infineon? I'm wondering just how fast they let people go in those R8's at Sears Pt.

Yes. After ordering the car in January, I was having a bit of buyer's remorse and wasn't sure I wanted to keep the order, so I went out there in April for two things. One to try out the R8 in a track setting and second to get at least a little familiar with the track since I'd also decided to try the Russell Advanced Racing Program which had just acquired Lola FJR-50s for their school.

Utah is right, the two day Audi DE is based on a lead/follow set up. The quality of your experience is going to depend to an extent on the abilities of the drivers in your group. Russell does try, to the extent they can, and in a diplomatic way, balance out group by ability. It certainly helps if everyone in the group is congnizant of the issue and willing to cooperate but ...... that said you are a bit at the mercy of the draw ~ i.e. who shows up for your group. In my case, I had a great time with the car at the April event. Russell was able to semi sort the whole group of, I think there were 10 then 8 of us over the two day to kind of match the fast drivers from the faster. Plus within the pod, my co-driver was willing to "slpit" (trade off) our drive rotations so that we each got rotations within the pod in the "faster" half.

If anyone is thinking of going, and I had a great time, one certainly enhances their odds of having a better time, by pairing up with a friend or friends they know, and trust.

Last but certainly not least, Bohdii based on Utah's comments and yours on the amount of track time etc your doing, if you haven't experienced something like the FJR50's, and are interested in a racing vs. just a well prepared and fast "street" car on a track, you owe it to yourself to try the Russell Advanced Racing program. I think you'll either be cured of, or hooked on aero enhanced cars :)

Cheers, see you on the track someplace. I'm talking to Miller about coming out to try and get signed off in one of the Mustang Challenge cars just for fun. If I do, and end up in SLC maybe we can get together for a drink if you are in town.

Last, getting back on point I'm finding that looking through TireRack's selection of wheels for the RS4, they only list 19" & 20 selections. But, on the brighter side, they do list BBS fitments for the RS4. 2nd, yes the R8 wheel bolt pattern are 5x112; not sure about the hub centric ring, but I think it's also the standard Audi (?? not sure if I have the right diameter) 67.5mm hub centric mount.

Mike
 

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Discussion Starter · #8 ·
Other Comparative Wheel Weights info:

Audi OEM 19" (weights were arrived at by weighing wheel w/tires installed and subtracting posted Pirelli tire weights, so .... I have my doubts about the ultimate accuracy of the results, particularly w/regard to the front rims):

Audi OEM 8.5 x19 ET42 US Dealer MSRP @$964 as of June 2008; estimated weight ~ 19 to 19½ lbs front 8.5x19 ET42; rear 11.0 x19 ET50 US MSRP $964and estimated weight 27 to 28 lbs

From the TireRack Website fitments for the R8 webpages:

OZ SuperLeggera III ~ 8.5x19" ET43 @ $1,015US 27.0 lbs; rear 11x19" ET not given, @ $1,055US, weight 29.0 lbs

OZ Galileo III ~ 8.5x19" ET not given @ $813 US 30.6 lbs; rear 11x19" ET not given, @ $861 US, weight 31.2 lbs

OZ Raffaello III ~ 8.5x19" ET not given @ $1,042US 27.2 lbs; rear 11x19" ET not given, @ $1,093 US, weight 28.0 lbs

OZ Botticelli ~ 8.5x19" ET not given @ $1,052US 30.0 lbs; rear 11x19" ET not given, @ $1,102 US, weight 33.0 lbs

From US Dymag distributor June 08 email, CarbonFiber & (?) Magnisum spoke
19x9" fronts, ET38 @ 16 lbs; rears 19x11" ET40 @19lbs. Cost, @ $2,455 each fronts, $2,540 rear. US distributor is WheelEnhancement.com

Hope this helps somebody
 

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Thnx Mike. Great info.

BTW,. Its great that you and I both have Porsche Caymans. The Cayman is such an awesome platform. Very superior to the 911. My dream day on the track should be happening very soon. It's when I will be able to trade off between the Audi R8 and the Turbo Cayman S, and see how they compare.
 

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Discussion Starter · #11 ·
Dymag performance wheel advantages

Just a performance wheel update claim. From a Dymag distributor site: ".... Carbon Magnesium Car Wheel - Summary The performance gain achieved by reducing the wheel mass (Un-sprung Mass) can be quantified using a factor of six. This means that to achieve the same performance gain by reducing the body mass, it is necessary to remove six times the wheel weight saving.

Example: A saving of 2Kg Per Wheel x 4 Wheels = Removing 48 Kg from the Bodywork.

In some instances, Dymag's Carbon Mag wheels have reduced the wheel weight by up to 5Kg per wheel, which equates to saving 120Kg from the bodywork to get the same performance advantage. ...." see, http://www.rotaryart.uk.com/acatalog/Dymag_Carbon_Fibre_Wheels_18.html

Hum, a potential 264 lbs, that's not insignificant. Still awfully costly however.

Cheers
 

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Hi All,
I've had my R8 now for a few months and have done 3 track days using the stock 19" P Zero's.
I'm now trying to select a dedicated track tire which I'll switch out for track days.

I noticed some in this post are using the Toyo R888.
The load rating for the rear matches Audi spec but the load rating for the fronts is 87 rather than 91. Should I be concerned about this? (235/35ZR19 87Y).

I'm also considering using 18" Michelin Pilot Sport Cups, but again having problems matching load ratings. The 18" rears (285/30ZR18) are rated at 93Y instead of 100Y.
I'm considering the 18" rather than 19" Sport Cups because I was told the 19's use a different tread compound that isn't as good as the 18s.

All help is appreciated.
 

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Audi R8's curb weight is 3439 lb (1560 kg)

The load index (87) is the tire size's assigned numerical value used to compare relative load carrying capabilities. In the case of our example the 87 identifies the tires ability to carry approximately 1,201 pounds.
Toyo R888
235/35R19 87 load index front
305/30R19 102 load index rear

1201 LB X 2 = 2,402 LB
1874 LB x 2 = 3,748 LB

These two pair of Toyo R8 tires will support a 6,150 LB vehicle.
http://marktg.toyotires.com/file/30029.pdf

Multiply load capacity by four tires to get your car's maximum load-carrying capacity

The higher the tire's load index number, the greater its load carrying capacity.

89 = 1,279 pounds
88 = 1,235 pounds
87 = 1,201 pounds
86 = 1,168 pounds
85 = 1,135 pounds
102 = 1,874 pounds


Typically, the load indexes of the tires used on passenger cars and light trucks range from 70 to 110.
Load Index Pounds Kilograms
Load Index Pounds Kilograms
71 761 345 91 1356 615
72 783 355 92 1389 630

87 1201 545 107 2149 975
88 1235 560 108 2205 1000
89 1279 580 109 2271 1030
90 1323 600 110 2337 1060
 
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