BBS LM "Tuner" Fitment Help - 19x8.5et18 (Front) and 19x11et25 (Rear)

[Slideways]

Any reason for going ET32s up front v ET18s on 19x8.5s?

Less camber and better tire wear for a street car. ET 18 is like putting a 26mm spacer on a CSL wheel.

[AbbeyRoad]

Less camber and better tire wear for a street car. ET 18 is like putting a 26mm spacer on a CSL wheel.

Thanks for the data (CSL ET44 on 8.5").

Having never seen a real CSL except in videos, I'm willing to roll the dice going with ET18s like the white E46 below.

[dustyice]

If anyone comes across this thread in the future, wanted to clear some misconceceptions which led me astray while research and ordering my own set of 19x8.5 +18 and 19x10 +25 (LM431/LM272).

1. The white M3 linked in the photos and the video is running the traditonal +32 fronts (LM227) not +18 (LM431).
2. 19x8.5 +18 fronts is more conservative than I had thought. This thread got me worried as I was not trying to run as much camber as I had previously running 18x9.5+22 at -3.7 deg. The19x8.5 +18 245/35/19 is fairly comparable to running squared style 67s 18x9 +26 265/35/18. If you want to see how they will fit put your stock 18s rears on the front if you have a set.

willtheyfit.com is also a great tool for comparing any fitment.

Here is my setup 19x8.5 +18 245/35/19 / 19x10 +25 275/30/19 (with a 5mm rear spacer) on PS4s running -2.5 deg front and -1.8 deg rear. No rub even driving hard. Both front and rear fenders are shaved so your mileage may vary.
Hope this helps!

[Tbonem3]

What is scrub radius, Alex

[dustyice]

What is scrub radius, Alex

The scrub radius is closer to stock than what I was running before at 9.5 +22 on a 265 or what many others run. If the main concern is twitchiness for street driving, camber choice typically has a larger real-world impact on stability and tire behavior than moderate scrub radius changes. Even lowering our vehicles alters suspension geometry in ways that can worsen steering behavior and effective scrub characteristics, but we all do it because the difference in CG is worth the downsides as long as we stay within the designed range of travel for the geometry.

The downside is of course there will be more load through my suspension and steering than stock, but remember offset is not related to the hub centerline, but the centerline compared to the width of the wheel. So the 1 inch decrease in width trumps the increase offset of 4mm comparing to my old setup. The old setup 9.5.+22 265 had an effective scrub radius increase of around 45mm more than stock and my new setup 8.5 +18 245 has a effective scrub increase of around 35mm, it is better than my old setup if you the goal is to be closer to stock. Will I feel it compared to stock? Yes. Will I feel it compared to my old setup? No. I consider the downsides of an aggressive camber setup to fit a wide wheel/tire to be much more critical to performance and stability than scrub radius.

All that aside none of this matters, no one is tracking their LMs so if performance is your main motivation you would not be in the market for heavy wheels like a LM.

[Tbonem3]

If you did correct measurements, then fair play. I would not have guessed that outcome. Though I'm surprised someone running LMs would even know/care about scrub radius. That's a bigger surprise ☺️.

[dustyice]

If you did correct measurements, then fair play. I would not have guessed that outcome. Though I'm surprised someone running LMs would even know/care about scrub radius. That's a bigger surprise ☺️.

I totally get it. let's just say they are not the most logical choice for a performance wheel, but I think they just look timeless! I also love suspension and did alooooot of research before picking these up because it is a very unconventional spec for sure.

[0-60motorsports]

If anyone comes across this thread in the future, wanted to clear some misconceceptions which led me astray while research and ordering my own set of 19x8.5 +18 and 19x10 +25 (LM431/LM272).

1. The white M3 linked in the photos and the video is running the traditonal +32 fronts (LM227) not +18 (LM431).
2. 19x8.5 +18 fronts is more conservative than I had thought. This thread got me worried as I was not trying to run as much camber as I had previously running 18x9.5+22 at -3.7 deg. The19x8.5 +18 245/35/19 is fairly comparable to running squared style 67s 18x9 +26 265/35/18. If you want to see how they will fit put your stock 18s rears on the front if you have a set.

willtheyfit.com is also a great tool for comparing any fitment.

Here is my setup 19x8.5 +18 245/35/19 / 19x10 +25 275/30/19 (with a 5mm rear spacer) on PS4s running -2.5 deg front and -1.8 deg rear. No rub even driving hard. Both front and rear fenders are shaved so your mileage may vary.
Hope this helps!

They look amazing Alex.

[Tbonem3]

I totally get it. let's just say they are not the most logical choice for a performance wheel, but I think they just look timeless! I also love suspension and did alooooot of research before picking these up because it is a very unconventional spec for sure.

Ya, I too am going to be forced into a not so great performance choice to fit a special set of wheels soon. I just hadn't seen such a low offset on a 8.5" before and assumed it would be even worse than the common 9.5et22.

[9kracing]

Ya, I too am going to be forced into a not so great performance choice to fit a special set of wheels soon.

I'm putting 19X10 +25 square on this weekend.

#yolo

[Tbonem3]

It's a lot of wheel! 265 or 275?