How to Identify Which Version of ARC-8 You Have

Many longtime Apex customers are aware that our most popular flow-formed wheel, the ARC-8, was overhauled around 2022. The ARC-8 design was improved with the new version being designated the “V2.” The ARC-8 V2 included specific improvements to the barrel design which brought the original ARC-8 design up to parity with some of our newer wheel designs in terms of the barrel’s internal shape and inner clearances.

This change allowed our 18” ARC-8s to be fitted to F87 M2, F80 M3, and F82 M4 cars that are equipped with the 380mm blue 4-piston calipers for the first time ever:

Click here to learn more about the 18” V2 ARC-8 on F8X applications.

Beyond clearing those larger OE brakes, this improved barrel design also improved clearance for certain aftermarket big brake kits. We’ve had many enthusiasts that already own a set of ARC-8s reach out over the years to inquire about the wheel’s brake clearances. The part numbers on your Apex invoices can be used to identify which version of the ARC-8 you have, and there is a small physical difference between the two versions of the wheel that can easily be identified without removing the wheel.

As you can see from the engineering rendering above, the V1 ARC-8 wheels feature a raised valve stem boss where the valve stem sits. The updated V2 wheels have a flush-mounted, non-raised valve stem boss. Additional photo examples below:

V1 Valve Stem Boss:

V2 Valve Stem Boss:

Additional notes: There are no alternate markings on the back pad of the wheels that will distinguish between V1 and V2 ARC-8s. In some cases, part numbers from original Apex invoices can be used to identify which version of the wheels you have. There is no set crossover date or invoice date that can be used to determine which version of the ARC-8 you have. This article only applies to the flow-formed versions of the ARC-8, not our forged offering.

Profile 1 or flat faced ARC-8s did not receive the barrel revision because they were not updated. Only the concave profile 3 ARC-8s have the updated barrel revision. Most chassis that require larger rotor diameters will automatically use the concave profile 3 ARC-8s.

This revision did not improve spoke side brake clearances.

If you’d like to confirm brake clearances or have more questions about the different versions of ARC-8s, please email us at expert@apexwheels.com. If you’d like to buy your next set of ARC-8s, head over to our ARC-8 wheel page here.

Tom M.

Tom is a BMW Fitment Expert at APEX Wheels. Prior to joining the company in 2019, he worked for BMW of North America as Fleet Manager: Portland (OR) for the ReachNow car-sharing program, and as Warranty Administrator/Loaner Fleet Manager at BMW Portland. In addition, Tom has extensive training in BMW TSBs (Technical Service Bulletins) as well as in-depth knowledge of all BMW chassis and their wheel fitment options, with and without aftermarket brake and suspension upgrades. His high-performance driving experience includes autocross events in southern Oregon and track days at PIR in his 2004 E46 330i with 17x9 ET42 APEX ARC-8 wheels. Vehicles he owned prior to indulging his passion for BMWs include a 1989 Jaguar XJ6 and a 2006 S197 Ford Mustang. Fun Fact: Tom is a huge Formula 1 fan. Have questions about wheels for your BMW? Use our contact form and ask for Tom.