APEX G42 2 Series Test Fitment: 19×9.5 ET25 square VS-5RS

As many of you know already, a few intrepid G42 customers have opted to run our 19×9.5 ET25 wheels square as an aggressive rotatable fitment. Stradale Design documented their test of this setup on their G42 on the following thread: https://g42.bimmerpost.com/forums/sh….php?t=1978825

While this was a fantastic initial impression of what this fitment was like on the 2 series, we had always planned to test this setup in-house as well. Since we needed scans of the larger ZTK brake calipers for another project, we dovetailed this testfitment in with an office visit used to collect brake data as well. Luckily enome was able to stop by our office with his ZTK-equipped G42 to help with this test fitment. His otherwise stock G42 was the perfect platform on which to test these wider wheels to compare against Stradale’s lowered example.

All of the final photoshoot photography featured the following specs.

G42 Specifications:

Suspension & Alignment: Stock

Spacers: None

Wheels: VS-5RS in Satin Bronze

Front & Rear: 19×9.5 ET25

Tires: Falken Azenis RT660

Front & Rear: 265/35-19

Front:

Overall the front fitment looks great, even at the stock ride height and with the stock alignment. We’ll touch on the tire model later but this is one of the wider 265/35-19 options on the market. The fitment is aggressive and might poke beyond the stock fenders of a non-ZTK car, especially with wider tire models. It is an extremely flush fitment which can be especially important if you need to run spacers. Bonus points for those who spot the F87 M2 CS Racing lurking in the background waiting for its time to shine…

Front Suspension: Strut Clearance

The photo above shows the strut clearances between the wheel and tire and the front strut assembly. The wide RT660 sits extremely close to the strut body. No tire witness marks or audible rubbing were noted with this fitment during the photoshoot but if driven aggressively on the track or street, a 3mm spacer would be a great addition to prevent the tire from contacting the strut when the tire sidewall flexes and deforms.

Above the tire, there is room between the tire and the OE spring perch. Aftermarket coilovers or HAS (height adjustable spring) kits that limit inner clearance because of a lower spring perch that sits further down than the OE configuration will need a wider (5-12mm) front spacer and additional negative camber to run this setup.

Front Brake Clearances: ZTK and More

Clearances were tight between the front ZTK calipers and the VS-5RS spokes, but they did clear without issue. There is plenty of clearance between the barrel of the wheel and the calipers which is where road debris and gravel are more likely to sit momentarily and get caught between the components. Overall the brake clearances for the 374mm ZTK brakes are acceptable with the VS-5RS but a 3mm front spacer would help build back that spoke-side margin if you’re concerned about road debris. We tested the VS-5RS and SM-10 19×9.5 ET25 wheel designs against these ZTK brakes, the 348mm front “MSport” brakes, and the base 230i brakes along with all applicable rear brakes and these wheels cleared.

Rear:

The rear fitment has less overall notes. Easy brake clearance and a ton of inner clearance for these wheels moved our focus to the fender clearance around the upper portion of the tire. Overall the fitment is once again quite flush especially with the wide RT660 tires. No rubbing was noted during our testfit, but the car was not driven hard. Extreme suspension compression and tire flex on track might lead to fender rubbing with wider tires which could be dialed out via alignment adjustment. The ZTK flares help with visual poke but aren’t a significant benefit to an otherwise unmodified car.

Tire Notes:

Falken RT660s are an excellent extreme-performance tire option that performs well on track. They also run quite wide. Per Tire Rack, the RT660s in the 265/35-19 size showcased here run 10.9” wide for their section width which is generally the widest point of the tire sidewall. A Michelin Pilot Sport 4s in the same size has a 10.6” section width. When moving further down to the contact patch, the RT660 has a massive 9.8” tread width while the PS4S has a 9.3” tread width. This is the portion of the tire that contacts the road, but it’s also the part of the tire we care most about when it comes to suspension and fender clearances as it’s this portion of the tire that is closest to these pain points. Both of these tires were measured on a 9.5” wide wheel.

The RT660s are wider at every point but are especially big where it matters most for us. The Michelins are a fairly wide tire already but they don’t come close to the RT660. I often get asked by customers what size of tire I recommend. It’s a hard question to answer because of variances like this within the same listed size by manufacturers trying to eke out more performance or chase various characteristics. 265/35s make sense here for a track performance setup but again the width and fitment will vary depending on the tire you select.

Alternate sizes:

While 265/30-19s could be used front and rear for a slightly easier fit, the tire model availability is far better in 265/35-19. A solid selection of track tires is available in this size making it the obvious choice for someone that tracks their 2 series. 255/35-19 has even better availability than 265 although most of the tires in this size are street oriented. You can run 255/35-19 for street tires on these wheels, but if you wanted an easy bolt-on fitment, the 255/35-19 could also be run on our 19×9 ET25 square fitment. As always, additional fitments can be found on our guide here.

Going Lower + Track Alignment: Featuring Stradale Design

As we mentioned already, Stradale Design is running the same setup on their G42 build as documented in their thread. At this point, most of you will have seen their thread already, but here are some shots of their car on these wheels with Falken RT660s lowered on MSS springs:

Once they dialed in some camber, these wheels tucked a bit more than is showcased here. In-depth photos can be found on their thread but we wanted to take advantage of this rare opportunity to compare and contrast a stock car with a lowered car. You can see some of the additional static camber gained from just from lowering the car at work helping to tuck the upper edge of the tire in despite the distance from the fender to the tire decreasing at the same time.

Aftermarket camber plates are going to be the best option to dial in additional negative camber up front from a wheel and tire fitment perspective as these will pull the top of the strut inward and improve fender clearance at the upper edge. Availability for plates like this is likely thin right now but as these cars get older more options should come onto the market.

Final Thoughts:

Overall these wheels work surprisingly well even on a stock car. Narrower street-oriented summer tires or all seasons would make essentially all aspects of the fitment slightly easier for street customers looking for a rotatable square fitment but this setup truly shines with aggressive track tires. We’ve been working on and building wheels for the 1 and 2 series chassis for years with the E82 and F2X 1 and 2 series and it’s great to see aggressive G42 fitments take shape. Owners right now may not be as interested in fitments that require some modifications but we hope this thread helps to give anyone interested in a rotatable square fitment for the track a great new option. These are also the most concave wheels available for the G42 2 series in our lines currently with an unmistakably deep face profile.

While this thread showcases our Forged VS-5RS, all the same notes apply to our Flow Formed SM-10 as well giving you multiple options at different price points. I’ve been a big fan of our Flow Formed wheels for a long time and while the forged wheels are great, if you need multiple sets to support a track program or want to save for suspension or HPDE fees, the SM-10s are a great option for any budget.

Even if you aren’t considering APEX wheels, we hope this showcase helps with notes about the offset and fitment on the G42. If you are considering our wheels, we’ve added this fitment to our guides and both of these wheels will be going on our G42 shop-by-vehicle page shortly.

A huge thanks goes out to our volunteer enome for giving up your time and lending us your car for a few hours. We hope to see you on APEX wheels again soon. Another thanks goes out to Stradale Design for picking up a set and letting us use your photos.

Let us know what you think about this fitment and if you have any questions!

-Tom and the APEX team

VS-5RS /// SM-10 /// Chassis Specific Guide