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      02-21-2012, 10:36 PM   #1
Eddy@ApexRaceParts
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Drives: E30 M3, 2011 335d
Join Date: Jun 2009
Location: Bay Area, CA

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Thumbs up the new ideal 17" track wheel

This is being posted here as this new fitment is very track/performance oriented. The ideal fitment would include wide rubber and negative camber. We've been waiting a long time for a wheel with these specifications. Check out the documented fitment test for the new 17" concave APEX ARC-8 wheels

Please note: This is a technical discussion about this new fitment. We cannot/will not discuss pricing or other purchase details in this thread. Please help us keep this thread on topic.

The E9X non-m fitment has long been lacking a 17" wheel with specifications that are ideal for track/street performance applications. Even the current 17" APEX ARC-8 wheels that are popular for this application are a compromise in width/offset for the non-m E9X, and they require spacers in many applications.

The new concave ARC-8 wheel sizes are wider, lighter, have more ideal offsets, and significantly improved Big Brake Kit clearance. Now 17x9's can be run as a square, rotatable, and spacer free setup with a more aggressive face design.

APEX ARC-8 17x9" ET30 - Satin Black Finish


APEX ARC-8 17x9.5" ET35 - Anthracite Finish


New Concave sizes:

17x8.5" ET20
17x9" ET30 - E9X non-m fitment
17x9.5" ET35 - E9X non-m fitment
17x10" ET25
17x10.5" ET27

Release Date:

Late April to early May
All sizes just received VIA certification in Japan last Thursday. They are now in production.

Improved Caliper Clearance:

The E9X brake caliper is located further back in orientation to the hub mounting point than most 3 series models. This means flat faced wheel designs leave excessive amounts of caliper to spoke clearance. Excessive clearance results in excessive wheel weight. Concave spokes make better use of the available space when lower offsets are needed. By using concave spokes we could decrease wheel weight by 1.5lbs when you factor in the weight of spacers needed on higher offset wheels. The inner barrel diameter was also increased to provide additional Caliper to barrel clearance. The original higher offset 17" wheels could not clear some 355mm kits. These new concave wheels clear Brembo and Stoptech 355mm kits with ease.

StopTech 355mm 6 piston BBK behind the new APEX ARC-8 17x9" ET30 test wheel


StopTech 355mm 6 piston BBK behind the new APEX ARC-8 17x9" ET30 test wheel



APEX ARC-8 17x9" ET30 Fitment details
This new fitment weights in at only 16.55lbs. This wheel is for those who want to run 255/40/17 and 245/40/17 tires square on 9" wheels. 335i and 328i customers looking to run 17x9" wheels up front are forced to run spacers with currently available high offset wheels to properly clear the strut tube when running a meaty tire. For example, members who are running our original 17x9" ET42 wheel need a 12mm spacer (30mm effective offset). Instead of adding spacer weight, this new wheel allows for a weight reduction while reaching the required offset for proper extreme summer and r-compound tire clearance.

Below is a test fitment of the 17x9" ET30 wheel on a pre-LCI E92 335i with a 255/40/17 Nitto NT-01 r-compound tire. This car has TC Kline coilovers, Vorshlag camber plates, and M3 control arms. With the camber plates set to the stock setting, this suspension already has around 1 degrees of negative camber due to the M3 control arms in combination with the lowered ride height.

The 255/40/17 NT-01's below are an r-compound tire. Their overall size is wider than most extreme summer tires, and other street tires. If a non r-compound tire were installed, there would be even more fender clearance.

Members are running the current 17x9's with 12mm spacers and 255/40/17's street tires without camber plates. Pulling the pins, and running camber as negative as possible within the factory limits is needed for a proper fitment. Camber plates are recommended for any 255 setup, but they are required if r-compound will be used.

17x9" ET30 strut tube clearance - TC Kline coilovers








17x9" ET30 Rear fitment test


17x9" ET30 Rear fitment test




APEX ARC-8 17x9.5" ET35 Fitment details
This new width/offset combo is ideal for a rear 9.5" direct fitment on all pre-LCI models or as a front fitment on modified E9X applications.

We will be testing this wheel on LCI models in the rear to understand if anything needs to be done for this to clear properly. This offset would set the tire just close enough to the fender that it will most likely clear with most tires, but some wider tire fitments may require minor fender rolling. Because we have not tested this yet, we cannot confirm LCI rear fitments at this time.

For this to fit the front properly, a 3-5mm spacer is required for strut tube clearance. Without the spacer the wheel is extremely close to the strut leaving no room for a tire. The chamfer on this wheel's center-bore was adjusted to provide additional contact with the wheel bearing hub, so they can easily accommodate a 5mm spacer and remain 100% hub-centric. All APEX wheels can accept a 5mm spacer, but this specific wheel was modified for even more hub contact.

If extreme summer or r-compound tires are used in 245/40/17 or 255/40/17 sizes, camber plates will be a must with this wheel size. Without plates the tire could contact the fenders.

Below is a test fitment of the 17x9.5" ET35 wheel on a pre-LCI E92 335i with a 255/40/17 Nitto NT-01 r-compound tire. This car has TC Kline coilovers, Vorshlag camber plates, and M3 control arms. In these photos the camber plates were pushed in to maximum negative camber mode. The photos clearly show that even with this r-compound tire, maximum negative camber is not required for the tire to clear the fender. Less camber could easily be run with the same tire, and even less if narrower tires are used.

17x9.5" ET35 + 5mm spacer: strut tube clearance - TC Kline coilovers


5mm spacer + max camber


5mm spacer + max camber


5mm spacer + max camber


5mm spacer + max camber


Rear Fitment





Please note: This is a technical discussion about this new fitment. We cannot/will not discuss pricing or other purchase details in this thread. Please help us keep this thread on topic.
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