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Discussion Starter #1
So I was today years old when I realised the R8 LMS Ultra actually runs a wider front track than rear track (when including wheels).

Stock Audi Gen1 R8 track measurements (hub-to-hub/no wheels):
front track 1638 mm
rear track 1595 mm

Stock Audi Gen1 R8 track measurements (including stock GT wheels):
front track 1744 mm
rear track 1747 mm

Audi R8 LMS track measurements (inlcuding Ultra wheels):
front track 1846 mm
rear track 1791 mm

I found this out because I picked up a set of Ultra wheels for my LMS conversion:
1617711802707.png

So I'm wondering how this will impact the feeling in the car. Does anyone have any experience of running wider front track? I assume it moves the car to an oversteer bias, especially when doubled with the fact the fronts are staggered only 1" slimmer than the 13" rears compared to the stock stagger of 2.5".
 

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So jealous man.
I’m hoping to have a surprise on this front eventually.

I really can’t wait to see your build.
 

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One thing to keep in mind too, there is spacers installed on the steering rack as well. They way you don't try and go for a full Uturn and mess up the car. I guess it also depends what tires you'll But you are right about the oversteer bias.
 

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Discussion Starter #4
So jealous man.
I’m hoping to have a surprise on this front eventually.

I really can’t wait to see your build.
Same! Really looking forward to your unique take on an LMS-inspired build man!

Finally got mine booked in! Car and all parts go into the shop mid May for about 6 weeks then I get her back in time for summer! :love:
 

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Discussion Starter #5
One thing to keep in mind too, there is spacers installed on the steering rack as well. They way you don't try and go for a full Uturn and mess up the car. I guess it also depends what tires you'll But you are right about the oversteer bias.
I didn't know this! So basically with these wheels fitted you can't go full steering lock without hitting something internal so need to install steering spacers? I will make sure I get this checked, I'll have 315/30R18 on the front and 335/30R18 on the rear, both notably smaller diameter to a track LMS purely due to the fact you can't get road tyres thick enough!

Thanks as always man!
 

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I think the Tires make a huge difference, We are running 325/660 18 in the front and 325/705 in the rear. Not that the rear matters. But I think your smaller might help, But I sill wouldn't go full lock to lock. These spacers can easily be installed if needed. When I get a chance later this week I will send a couple pictures of them installed on the rack.
 

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Discussion Starter #7
I think the Tires make a huge difference, We are running 325/660 18 in the front and 325/705 in the rear. Not that the rear matters. But I think your smaller might help, But I sill wouldn't go full lock to lock. These spacers can easily be installed if needed. When I get a chance later this week I will send a couple pictures of them installed on the rack.
That would be amazing thank you! Like you say I could probably get away with it by never going full lock myself but I'd rather have it mechanically prevented just in case!

My fronts would be 647mm diameter total so only 13mm less than yours actually so I likely will encounter this problem! Thanks again mate.
 

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Same! Really looking forward to your unique take on an LMS-inspired build man!

Finally got mine booked in! Car and all parts go into the shop mid May for about 6 weeks then I get her back in time for summer! :love:
Holy crap man. That’s so awesome!
 

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Discussion Starter #9
Holy crap man. That’s so awesome!
Did a test fitment of the wheels today to check if they do indeed clear my CCB's....

They do!
1617803900229.png 1617803937077.png

So you heard it here first, these 18" wheels clear CCB's!

I did however hit a snag. When flush to the hub the wheel is so wide it would actually just touch the suspension elements! Tbh I didn't expect this, looking at all the blueprints I couldn't see any key shape difference in the LMS structure.

However I did notice a difference in the mounting bell on the ceramic discs:

Stock:
1617804387578.png

LMS:
1617804443020.png


On my stock ones the bell mount in sunken/recessed by about 10mm. Whereas looking at the first LMS equivalent the bell mount is different and doesnt sink at all, meaning the mounting point of the wheel is potentially 10mm wider?

Or am I missing something? @SpeedOneMotorsports I wonder if you can think of anything to explain the lack of clearance against the inner suspension parts? Does the LMS run a wider track or different suspension placement to the stock car?
 

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I can't help with your question but a small spacer, say 5mm, may give you the clearance you need.
 

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Discussion Starter #11
I can't help with your question but a small spacer, say 5mm, may give you the clearance you need.
Thanks Trev, exactly what I'm thinking. I'm getting a set of centerlock adapters made by Braid which are usually 5mm thick, essentially acting as a 5mm spacer. I'm going to do some accurate measuring to see what kind of spacing I need and can get Braid to accomodate. Hopefully it's less than 10-15mm I need as I've never been a fan of thick spacers, especially on the fronts!
 

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Thanks Trev, exactly what I'm thinking. I'm getting a set of centerlock adapters made by Braid which are usually 5mm thick, essentially acting as a 5mm spacer. I'm going to do some accurate measuring to see what kind of spacing I need and can get Braid to accomodate. Hopefully it's less than 10-15mm I need as I've never been a fan of thick spacers, especially on the fronts!
Yes I'm in agreeance when it comes to using thick spacers. I'm sure Braid will come up with a satisfactory solution.
 

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I am assuming you are mounting up to a stock set up right now? If so that would explain it. Once you have the adapters made I am sure it will fit. The LMS is a TIGHT fit.
 

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So I was today years old when I realised the R8 LMS Ultra actually runs a wider front track than rear track (when including wheels).

Stock Audi Gen1 R8 track measurements (hub-to-hub/no wheels):
front track 1638 mm
rear track 1595 mm

Stock Audi Gen1 R8 track measurements (including stock GT wheels):
front track 1744 mm
rear track 1747 mm

Audi R8 LMS track measurements (inlcuding Ultra wheels):
front track 1846 mm
rear track 1791 mm

I found this out because I picked up a set of Ultra wheels for my LMS conversion:
View attachment 260628

So I'm wondering how this will impact the feeling in the car. Does anyone have any experience of running wider front track? I assume it moves the car to an oversteer bias, especially when doubled with the fact the fronts are staggered only 1" slimmer than the 13" rears compared to the stock stagger of 2.5".
Yes you and @SpeedOneMotorsports are correct. The increased track width will decrease understeer/increase oversteer and the much wider front tires relative to the rear will take it also another step toward much less understeer.

Increased track width at the front reduces weight transfer at the front versus the rear so the rear would brake away sooner than stock. And wider front tires relative to the rear (versus the stock widths) will give you more front grip. Both of these should be a pretty significant change in balance and meant for the track and much higher aero.
 
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