- The E92 M3 Competition is factory equipped with the desirable, tighter-handling ZCP suspension package, but we still swapped it out.
- AST Suspension’s renowned 5100 Series uses race-proven technology to provide better suspension geometry in road and track environments.
- SPL Parts offers high-quality custom performance alignment arms and spherical bushings for street vehicles.
- BBS RI-A forged wheels are based on the same concept as RAYS Engineering’s Super GT design.
It hasn’t been that long since we introduced our Project E92. If you missed it, it’s a 2013 BMW M3 Competition (LCI) with a dual-clutch transmission, carbon fiber roof, and finished in Jerez Black. In our last article, we improved upon the aural delight of the stock S65 V8 powerplant by equipping an Akrapovič titanium exhaust. Other areas of the vehicle still need upgrading, though. Most will be a bit more involved but yield a more visceral experience than the factory spec. The crucial areas of suspension, wheels, and tires are on today’s agenda. We again visited our friends and technical wizards at R/T Tuning in Montgomeryville, PA, to complete the installation. Let’s get into the new mods!
AST 5100 SERIES COILOVERS
Since its inception in 2000, AST has continuously evolved and improved. Developing more advanced and specialized motorsport-derived suspension systems for competition and road use. Now, AST does offer its heavy-duty 5200 series. However, because we’re going for a more streetable setup, we selected the 1-way monotube 5100 Series, which utilizes inverted technology. A race-proven design, inverted technology produces an extremely strong damper, offering better suspension geometry under heavy lateral and braking loads, which can be experienced during either road or track driving. By incorporating a knob for rebound adjustment, the 5100 Series allows fine-tuning of the shock absorber’s extension rate. With the monotube design, a floating piston separates the oil and nitrogen, allowing for a larger piston and increased damper performance. Other features include steel threaded shock bodies, height-adjustable collars, and 14mm diameter internal pistons. We really like that these utilize the factory mounting locations. Still, our favorite aspect is the ability to revalve them for specific characteristics. That, and they’re fully serviceable and rebuildable, which will come in handy after navigating the treacherous Pennsylvania roads for a spell.
SPL PARTS SUSPENSION ARMS & BUSHINGS
Whether you get your kicks behind the wheel of purpose-built racecars or high-performance street applications, SPL Parts has the suspension solutions you need. Its products provide increased adjustability and performance for all custom alignment needs. Using the highest quality USA-sourced construction materials and innovative features, like its unique adjuster design, it has become a household name. With its products CNC machined and made in the USA, it’s only fitting that the company utilizes in-house research, development, and quality control. So, which products from the SPL Parts catalog did we source for Project E92? If SPL makes it for the E9x chassis, we added it to the list. So, let’s just say all of them, including the front lower control arms, front tension rods, rear toe links with eccentric lockout, front sway bar end links, rear sway bar end links, rear upper arm links, tie rod ends, and the oh-so-important front caster rod monoball conversion. If it sounds like a lot, that’s because it is, but replacing the factory rubber bushings with spherical bearings will eliminate unnecessary play in the suspension, providing a much tighter, more responsive, and better-connected handling experience.
BBS RI-A WHEELS
A name that needs no introduction is BBS. This juggernaut of the motorsport, wheel, and general aftermarket product industries has been crafting quality offerings since 1970. Most known for its wheels, you’d be hard-pressed to find someone involved with the automotive lifestyle that wasn’t immediately familiar with the name. Due to its storied presence in the highest forms of motorsport, it was the obvious choice for rolling mass on Project E92. Considering the new products that BBS has available, we went with the forged RI-A model. Based on the same concepts as its solution in Japan’s famed Super GT racing series, the RI-A is also one of the wheel maker’s newest and most alluring designs. Produced explicitly by BBS Japan, we went with the RI-A045 and RI-A046 models measuring 18×10-inch +25 in the front and 18×10.5-inch +22 in the rear. Due to the unique forging process, these wheels weigh a scant 18.9 and 20 pounds, respectively. Finished in Diamond Black, the wheels also feature black with gold center caps and antislip paint on the tire mating surface.
MICHELIN PILOT SPORT 4 S TIRES
Derived from the legendary Pilot Super Sport, Michelin’s new max performance summer tire, the Pilot Sport 4 S, was our pick for rubber. Outstanding grip, precision steering control, and a streetable design that doesn’t leave you stranded in inclement weather made this a no-brainer. Using the brand’s Dynamic Response Technology, the tires continuously adapt to the road for performance and longevity. With multi-compound construction, the 4 S offers increased dry or wet grip whether you’re cruising the road or attacking the occasional track day. Best of all, it’s backed by a 30,000-Mile Manufacturer’s Warranty against any defects in workmanship or materials. To maximize the E92’s grip levels, running a 265/35ZR18 on the 10-inch-wide front wheel and squeezing a 295/30ZR18 on the 10.5-inch-wide rear was the right decision.
Using our patented dog scale of difficulty, I’d assign today’s installation process a medium dog difficulty (almost only suitable for the big dogs). Fitting the suspension and various arms involved with our upgrades is not very difficult. Yet, some areas require specialized tools, like a press, tire mounting machine, and the knowledge of alignment specs to ensure all arms continue properly aiming the car down the road. For that reason, as we mentioned, we’re back at R/T Tuning in Montgomeryville, PA, to conduct the installation.
Earlier, we mentioned a major positive of the AST 5100 setup: it maintains factory mounting points. Anyone familiar with fabricating custom mounting solutions for motorsport dampers knows how much easier it is when items bolt into place. Such is the case with the E92-spec AST 5100, which not only maintains the divorced spring setup in the rear, but the heights of each product nearly match the factory components. The only holdup on these was setting the car at the correct ride height to clear the orange sway bar end link mount threaded onto the front coilover.
With the factory suspension dismantled at various points on the car, Pat at R/T Tuning installed the adjustable arms from SPL Parts in their corresponding factory locations. Not before spinning each component and rod out to match the factory arm lengths in preparation for making finer adjustments later on R/T Tuning’s in-ground Hunter laser alignment rack.
One of the arms that required further provisions was the front caster rod monoball bushing. A modification whose install steps we similarly covered in our F80 M3 suspension article. The stock bushing will need to be pressed out of the arm, and its enhanced spherical bearing will be pressed into place in the same component.
Other components that require more effort than the standard bolt-and-go are the front tie-rod ends. Not only produced with a unique clamp design instead of a jam nut but also roll center adjustment, these tie rod ends will aid in bumpsteer removal.
Next, Pat rounded out the installation using a Hunter touchless tire mounting machine to strap the Michelins to their final resting place on the BBS RI-A wheels. Lastly, perching the E92 atop R/T Tuning’s Hunter in-ground alignment rack and trueing up all of the angles. There’s plenty more to come on Project E92, so stay tuned for the next phase of modifications.