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      12-03-2017, 01:03 PM   #1
Asbjorn
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Need help confirming custom wheel dimensions

I am placing an order for custom made forged wheels tomorrow, and was hoping someone could help me confirm below dimensions. I would like to avoid any possibility of scraping, and have tried to select "safe" et values instead of going for a bolder look. Car is not lowered. Please let me know if you think the numbers are spot on?

Stock front: 8J 18 et 29. New front: 8.5J 18 et 35 (probably 225 tires)
Stock rear: 8.5J 18 et 40. New rear: 9.5J 18 et 40 (probably 255 tires)

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      12-05-2017, 04:37 AM   #2
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Hey mate, long time not seen, hope you 're doing great.

You are good to go on that sizes both et and tires dimensions, perhaps even et35 rear for a more flush result.

...but... custom? forged? really? Besides when on 18' mine handled -unfortunately- far better on rft and thus oem would be mandatory for me (that or I 'm just getting older).
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      12-05-2017, 02:14 PM   #3
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Quote:
Originally Posted by jannisa View Post
Hey mate, long time not seen, hope you 're doing great.

You are good to go on that sizes both et and tires dimensions, perhaps even et35 rear for a more flush result.

...but... custom? forged? really? Besides when on 18' mine handled -unfortunately- far better on rft and thus oem would be mandatory for me (that or I 'm just getting older).
Wow, great to see that the forum is still endowed with your presence!

Thanks for confirming the dimensions. And yes, I am really going for this unusual custom order. Reasons being:

1) I want to keep the oem design, but the sizes above are not available from BMW. I really like the oem spoke design in combination with the color of my particular car, and 18" is neither too big or too small for my tastes.
2) I always wished the spokes would be more concave, which will now be possible through custom design with 9.5J instead of 8.5J as the ET is unaltered.
3) I always wanted the rear wheels to be more similar to the front wheels in terms of how they flush with the car. This again should automatically happen as I go up in width.
4) As for the increased front width, I just wanted to stretch out and stiffen my current 225 Yokohama AD08Rs a bit.
5) After 100.000km in China, my original wheels are not very round anymore. One of them also got repaired due to a crack. New oem wheels are very expensive in China, more so than custom-made forged wheels.
6) I have chosen forged wheels as they weigh in at around 8.5kgs (-25% or so below the oems). I am really looking forward to see if I can feel the difference.

As for handling with RFT on 18, I personally only miss the direct steering feel they offered. For me, everything else has improved with the AD08R nonRFTs I currently use. However while my car is still on oem springs (non M sport), I recently switched to Koni FSDs. I like to think these dampers removed the comfort added by nonRFTs, resulting in a more OEM-ish balance of sport and comfort, while not having the weight transfer and un-sprung mass problems associated with heavy stiff tires and soft dampening.
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      12-05-2017, 03:43 PM   #4
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If you're going with custom wheels, your wheel widths are fine, but I would suggest more offset. For the front I would go at least et 30 wheels and at least 235 tires (the factory even puts a 255 on a 8.5 wheel for example)
Then for the rear, you can easily do et 35 wheels and a 265 tires... I'm running an et 35 wheel with a 275 tire and my car is lowered....

Here is my setup with H&R lowering springs for example...
Front - 19 x 8.5 et 35 w/10mm spacers (basically et 25) and 235 tires
Rear - 19 x 9.5 et 35 with 275/30 tires...


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      12-06-2017, 03:17 AM   #5
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Many thanks for your kind words mate, my thoughts exactly towards you too.

I actually sold mine last year, wasn't active on our forum but was very glad to see your current post and had to say hi.

Well it sounds that you 've got yourself a deal, looking forward to seeing your new wheels on, ''293s'' with more concave I bet will look stunning.

Have a good one m8.
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      01-03-2018, 05:43 AM   #6
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Based on the advice above I ended up with

Front: 235/40R18 | 8.5J ET35
Rear: 265/35R18 | 9.5J ET40

As explained I did not want to go all in, but just compliment the original design.
At this point I am 100% satisfied with the result. The wheel design turned out to be 95% OEM, while noticeably lighter. Also everything seems to be a perfect fit.













I absolutely love how all of the mods on this car are still undetectable unless you really know the E89-series well:

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      01-07-2018, 04:29 AM   #7
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Job done, very nice mate, the new wheels transformed the car completely lol.

Jokes aside enjoy them in full and Happy New Year btw.
Cheers
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      01-09-2018, 01:27 PM   #8
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Quote:
Originally Posted by jannisa View Post
Job done, very nice mate, the new wheels transformed the car completely lol.

Jokes aside enjoy them in full and Happy New Year btw.
Cheers
Thanks Jannisa! The new wheels had their first day at a damp track today:



Still learning, and trying to understand what is right and wrong on the track.
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