This past month, I celebrated one year of ownership with my F30 340i with a brand new set of wheels and tires. I put a lot of time and research into finding what I believe to be the perfect wheel setup for this car. I’ve taken everything I’ve learned from each set of wheels I’ve owned and applied it to this setup.
Maybe I’m getting older, but I’ve grown to appreciate the OEM+ look. I used to think, if I’m going to spend the money on a set of wheels, I want it to be obvious that I’ve upgraded them. This time, I was looking for a performance oriented wheel that could pass for a factory design. My search led me to the APEX ARC-8R, a simple split spoke forged wheel that accepts BMW center caps.
Specs:
Front: 18x8.5 ET35
Rear: 18x9.5 ET45
Bolt pattern: 5x120
Center bore: 72.56
Weight: 18.35 lbs front, 18.7 lbs rear
Load rating: 1,800 lbs
Having owned 17’s, 18’s and 19’s, I keep coming back to 18’s as the perfect wheel size for me. Big enough to accommodate large M Sport brakes without clearance issues, yet small enough to fit larger tires without rubbing. They are just right. This time around, I went with 18x8.5 ET35 for my front wheels and 18x9.5 ET45 for the rear. This is perfect, no-nonsense fitment for the F30. With these specs, there’s no spacers, brake clearance issues, suspension clearance issues, or tire rubbing, even on a lowered car. Both the front and rear wheels are flush to the body. Since the ARC-8 doesn’t have a lip, it gives the illusion that the wheels are larger than they actually are.
F30’s, like many BMW’s have a bolt pattern of 5x120 and a center bore of 72.56 mm. If you are new to the wheel game, center bore is the hole on the backside of the wheel where it mounts to the hub. If you buy a wheel where the center bore is too large, you can use an adapter called a hub centric ring to fill in the gap. If the center bore is too small, the wheel simply won’t fit without being drilled out by a machine shop. Some brands like APEX and VMR who cater to the BMW market offer wheels with a 72.56 mm center bore so the wheels fit straight out of the box.
Cast VS Flow Formed VS Forged
Cast
In the world of aluminum wheels, there are three main manufacturing processes; cast, flow formed and forged. Cast aluminum wheels are the most common and affordable. Most factory wheels that cars come with are cast. Or if you’ve been wheel shopping and have seen wheels that are $1,000 or less for a set of 4, they are most certainly cast. To put it simply, cast wheels are made by pouring molten aluminum into a mold, allowing it to cool, and out pops a wheel. Because cast wheels are the weakest of the 3, they require more material to be structurally sound, making them the heaviest wheel construction.
PROS
Affordable
Huge selection of designs
CONS
Weakest construction
Heavy
Flow Formed
“Flow formed” is a term that’s been popping up in the wheel world in recent years. With flow forming, they start with a cast wheel and then use a machining process to apply pressure to the inner barrel of the wheel to compress the aluminum, thereby increasing its strength. Flow formed wheels offer a middle ground between cast and forged wheels. They are generally stronger and lighter than their cast counterparts, while being more affordable than forged wheels. They are for the enthusiast who is willing to pay for more than just a wheel’s design.
PROS
Lighter and stronger than cast
More affordable than forged
CONS
Spokes are still cast aluminum
Not as many options, but more designs have been coming to market recently
Forged
The ultimate, spare no expense wheel construction is forged. With forged wheels, they start with a block of aluminum and according to APEX’s site, apply 10,000 tons of pressure, then machine out the spokes. The result is a wheel that is both extremely strong, and extraordinarily light weight. A forged APEX ARC-8R weighs just over 18 lbs. For context, the stock BMW Style 407’s that came on my car weighed 29 lbs without tires. You don’t need to get your calculator out to realize that’s a massive weight savings. All this performance comes at a cost though. Forged wheels are the most expensive by far.
PROS
Lightest and strongest wheels
CONS
Expensive
There was a time when the high cost of forged wheels from brands like BBS or Rays Engineering made them unattainable to the average car enthusiast. A set of BBS FI-R will set you back $8,000 (I sold my E90 for less than that!). Recently, brands like APEX and Forgestar have been shaking things up with more affordable forged options with the APEX ARC-8R’s coming in at around $650 per wheel. Not “cheap,” but you don’t need to donate a kidney (cough.. BBS.. cough..). Still, if you can’t stomach the cost of a fully forged wheel, APEX offers a flow formed version of the ARC-8 for around half the price.
My favorite thing about my ARC-8R’s is, despite the technology and performance that’s engineered into them, they look like they could have come on the car. Especially with the BMW center caps and brushed silver finish. The slight concave of the spokes and “FORGED” engraving when you get up close are the only hints that would give them away as aftermarket wheels.
Tires
Let’s talk tires. On my last setup, I had the Michelin Sport 4S which is a high performance summer-only tire. This time I chose the Michelin Sport All Season 4. As great as the Sport 4S were, I really had to step back an evaluate my needs as a driver. While I don’t plan to ever drive my 340i in snow, I do like having the option to drive in cold weather which is about 65% of the year in Michigan. The tread pattern on the All Seasons gives me more confidence driving in heavy rain. Because I’m not tracking the car to pushing it to the limit on a regular basis, the advantages of the All Seasons outweighed the top end performance benefits of the Sport 4S for my personal use case.
One thing that was important to me was choosing tires that fit properly with no stretching. I went with 245/40/R18 for my front tires and 275/35/R18 for the rear on an 18x8.5 and 18x9.5 respectively. To me, this is the perfect tire to wheel ratio for the F30 and offers a comfortable ride for daily driving. The sidewall of the tire is squared off - a look that I’ve come to favor over stretched tires with rounded sidewalls.
HUGE thank you to my sponsor Kies Motorsports for sending me these wheels. I was actually planning on buying them outright, but coincidently, Kies became an APEX distributor as I was in the market. It’s cool when things work out like that! Anyway, if this article helped point you in the direction of a set of APEX’s, I earn small commission if you use my affiliate link :) If you want to use this information to buy another brand, that’s cool too!