[RS61]

I've got an 2021 LCI F90 M5 Competition and take it to a lot of track days (I wrote up a long post on this last year).

I run Cup 2 tyres, and even though they have a really strong sidewall the outside of the fronts wear extremely quickly, tearing off big chunks of rubber within just a few track days, even though the rest of the tyre is minimally worn.

Having spoken to some alignment specialists, they've all said that it's a problem with the factory camber settings, but that the camber on the front is not adjustable at all. Lowering the car adds a tiny bit of negative camber but that's insufficient for proper track driving.

I need to find a replacement adjustable front upper arm which allows for camber adjustment. Does anyone know where I can find one of those?

[pbonsalb]

Would eccentric bolts on each side offer enough adjustability? Surprised no one sells them. There is probably some existing application but finding it could be challenging.

[stealth70mde]

Originally Posted by RS61

I run Cup 2 tyres, and even though they have a really strong sidewall the outside of the fronts wear extremely quickly, tearing off big chunks of rubber within just a few track days, even though the rest of the tyre is minimally worn.

I have the same problem you have…

[Boosted_8]

I'm using these (on a G30 rather than F90). I don't know if they are interchangeable. Got me to -1.6 on the front.

Springs and dampers stock + F90 roll bars

[Maverik259]

Originally Posted by Boosted_8

I'm using these (on a G30 rather than F90). I don't know if they are interchangeable. Got me to -1.6 on the front.

Springs and dampers stock + F90 roll bars

Should be the same

[warpeacelove]

Same thing for both as they have the same Chassis

[SGMM5]

BMW sells replacement upper arms to adjust the camber. I got a set to increase the negative camber but haven't installed yet. I'll see if I can find the part numbers but if you look on getbmwparts or similar site they come up for the F90.

[SGMM5]

They aren't adjustable though, so an aftermarket option that is may be better. I searched for an adjustable solution but didn't find anything I was confident in. Those G30 ones look interesting

[RS61]

Very interesting. The alignment guys had actually installed those Hardrace arms on a G30 and had good things to say about them. I was worried about whether they'd be durable enough for an f90 doing track work, as they don't seem to be made specifically for the M5. Any thoughts?

And if you do find the part number for the bmw negative camber arms would love to check them out.

[warpeacelove]

Originally Posted by RS61

Very interesting. The alignment guys had actually installed those Hardrace arms on a G30 and had good things to say about them. I was worried about whether they'd be durable enough for an f90 doing track work, as they don't seem to be made specifically for the M5. Any thoughts?

And if you do find the part number for the bmw negative camber arms would love to check them out.

Once again the G30 Chassis is the same chassis the F90 is built on.

[TimmyBHGM5]

Have you found any solutions yet? I'm in need for more negative camber too. I'm thinking of only lowering the front, and get an adjustable arm.

[pbonsalb]

What is your current negative camber? I have 1.5 negative and think that is fine. If you want more, buy the hardrace upper wishbones.

[TimmyBHGM5]

Originally Posted by pbonsalb

What is your current negative camber? I have 1.5 negative and think that is fine. If you want more, but the hardrace upper wishbones.

The car is completely stock, and is a base M5, I don't know the camber degree, maybe I should first try a HAS kit to get more negative camber since the car is a base M5?

[pbonsalb]

Lowering a little will increase the negative camber a little. Not half a degree. Maybe a tenth or 2. I use H&R M5 springs. Those into cosmetics prefer the M550ix version that lower more but I am not sure they are as stiff as the M5 version. I’d probably go HAS kit if I wanted to go low.

[RS61]

Need some help guys. Had Center Gravity install the Hardrace arms today and they actually allowed for less camber, not more. The standard arm allows for negative 1.25 at the front but we need more to mitigate the outside tyre wear. The hardrace arms only allowed up to 1, and even with some customisation only got to under 1.2, so even worse. Any thoughts as to how this can be solved? @Boosted_8 did you have to do anything special to achieve your 1.6?

[PDOT]

What is the goal camber for tracking?

[RS61]

For anyone interested I got this sorted in the end. Turns out bmw do special order upper arms with either more or less camber, typically used when cars have had an accident and the chassis is out of shape. So I've installed the negative camber arms, as well as the m performance suspension and the dinan metal ball joints and we're in the game. Turn-in is super sharp and the outside of the tyres is taking a lot less pounding on track.

[crypto]

Originally Posted by RS61

For anyone interested I got this sorted in the end. Turns out bmw do special order upper arms with either more or less camber, typically used when cars have had an accident and the chassis is out of shape. So I've installed the negative camber arms, as well as the m performance suspension and the dinan metal ball joints and we're in the game. Turn-in is super sharp and the outside of the tyres is taking a lot less pounding on track.

Always nice when people update threads. So what is/was the camber number you were trying to achieve and what does this solution (special order arms + suspension change) get you too? It sounds like there isn’t an acceptable adjustable option — so do you just use these upper arms when tracking and swap the originals on when going back to everyday driving?

[CrashCade]

I also am interested in what you were able to achieve for camber with the special order arms you bought. Do you have part numbers by chance?

Also, are the Dinan ball joints that big of an improvement? Have you looked into the Dinan rear suspension link kit, interested in feedback on that if so.

[RS61]

So I got it to -1.5 all round, and now the outside of the tyre holds up much better during track days which is the main reason I did it. It's a bit more pointy so in normal driving needs a bit more attention, but nothing major so I just have this whole setup on the whole time.

Part numbers for the arms are B31.10.8.053.331 and 332

It's quite hard to tell if the Dinan ball joints were worth it actually. Because I did a bunch of changes together it's impossible to tell if they've made the steering better or worse. In hindsight I wouldn't have done it, and would have only done the drop and the arms and then reviewed.

I did consider the Dinan rear suspension link kit too originally but the feedback from my suspension guys was that it wasn't particularly impactful on this platform.

[PDOT]

The ball joint didn't improve much, but the rear toe link made a huge difference when I hit the track.

So after the drop and the upper arm, you're at 1.5? I was thinking about doing the upper arm but haven't done a drop, so it doesn't seem like it would do much.

[Boosted_8]

Originally Posted by RS61

Need some help guys. Had Center Gravity install the Hardrace arms today and they actually allowed for less camber, not more. The standard arm allows for negative 1.25 at the front but we need more to mitigate the outside tyre wear. The hardrace arms only allowed up to 1, and even with some customisation only got to under 1.2, so even worse. Any thoughts as to how this can be solved? @Boosted_8 did you have to do anything special to achieve your 1.6?

No sorry, there are several minor differences between G30 and F90 which I guess didn't work out. Glad you found a valid work around in the end.