The soul of the machine bestows its unique personality, a subtle quintessence that murmurs within each contour and radiates from every skillfully crafted edge. The BMW E90 stands as a prime example, a magnum opus of mechanical ingenuity, etching its distinct mark in the chronicles of vehicular legacy, a tribute to the unwavering commitment and fervor of its creators.
As we embark on this journey together, dear BIMMERIST readers, we shall delve into the realm of chassis modification and the best upgrades available for the indomitable BMW E9x Chassis. It is a tale of obsession, of the pursuit of perfection, and of the relentless spirit that drives us, the loyal enthusiasts, to elevate our beloved Bavarian chariots to new heights.
In the following pages, we will guide you through the labyrinth of chassis mods, from suspension setups that defy the laws of physics to the subtle art of weight reduction, all in search of that elusive ideal: the perfect union of man and machine. Each mod has been meticulously researched, scrutinized, and tested, ensuring that your E90 emerges from this metamorphosis as a leaner, meaner, and more captivating incarnation of its former self.
So, dear reader, buckle up, and let us embark on a thrilling adventure through the world of BMW E90 chassis modifications, where passion and precision dance a tantalizing tango of automotive delight. Prepare to unleash the latent potential that lies dormant within your machine, and witness your E90 ascend to the pantheon of legendary Bimmers.
Suspension Upgrades
Coilovers
One of the most significant suspension upgrades for the BMW E90 is the installation of a high-quality coilover system. Replacing the stock suspension with coilovers offers numerous benefits, including improved handling, reduced body roll, and a more aggressive stance. The adjustable nature of coilovers enables you to fine-tune your E90’s suspension to your driving style and preferences. Some of the top brands to consider include KW, Bilstein, and Öhlins, each boasting unique features and characteristics to cater to your specific needs.
Customization and tuning
To get the most out of your coilover system, it’s crucial to understand the art of suspension tuning. Experimenting with spring rates, damping, and ride height adjustments can transform the handling characteristics of your E90, allowing for a personalized driving experience. Consulting with a professional tuner or experienced fellow enthusiast can help you find the perfect balance between performance and comfort.
Sway bars
Upgrading sway bars, also known as anti-roll bars, can significantly enhance your E90’s stability and cornering performance. Stiffer sway bars reduce body roll, keeping the car flatter through corners and providing better grip and steering response. This modification is particularly beneficial for spirited driving, track days, or those seeking a more agile feel on the road.

When choosing sway bars for your E90, consider options from reputable brands such as H&R, Eibach, and Dinan. These manufacturers offer various sizes and materials to suit your desired level of stiffness and weight savings. Don’t forget to pair upgraded sway bars with quality end links and bushings to maximize their effectiveness.
Bushings and mounts
The E90’s factory rubber bushings and mounts can wear over time, leading to a less precise and less responsive driving experience. Upgrading to polyurethane or solid metal bushings can dramatically improve your vehicle’s responsiveness, handling, and overall feel. Key areas to consider upgrading include control arm bushings, subframe bushings, and differential mounts.
While the benefits of upgrading bushings and mounts are undeniable, keep in mind that the installation process can be labor-intensive and may require specialized tools. Additionally, stiffer bushings may result in increased noise, vibration, and harshness (NVH) levels. Consult with a trusted mechanic or experienced enthusiast to determine the best setup for your desired balance of performance and comfort.
Weight Reduction
Carbon fiber components
One of the key tenets of performance tuning is reducing weight to enhance your vehicle’s acceleration, handling, and braking. Carbon fiber components are a popular choice for shedding pounds from your E90, as they are not only lightweight but also incredibly strong and aesthetically pleasing. By reducing your car’s overall mass, you allow the chassis, suspension, and engine to work more efficiently, resulting in a more agile and responsive driving experience.
Many aftermarket parts are available in carbon fiber, allowing you to replace heavier stock components with these lightweight alternatives. Some popular choices for the E90 include carbon fiber hoods, trunks, and roof panels. Additionally, you can opt for carbon fiber interior components such as door panels, center consoles, and even seats to further reduce weight.
Stripped interiors
For those seeking the ultimate in weight reduction, stripping the interior of non-essential items can lead to substantial weight savings. This may involve removing the rear seats, carpets, sound-deadening material, and even air conditioning components. While this approach can significantly improve performance, it’s essential to carefully consider how it will affect your vehicle’s comfort and usability, especially if it’s a daily driver.
It’s crucial to strike the right balance between weight reduction and comfort. Consider what aspects of your E90’s interior you are willing to sacrifice in the pursuit of performance. Partial stripping, such as removing only the rear seats or reducing sound deadening, can provide a compromise that still yields noticeable improvements in handling and acceleration without sacrificing too much daily usability.
Lightweight wheels
Upgrading to lightweight wheels can have a significant impact on your E90’s performance, as it reduces unsprung weight and rotational mass. This results in quicker acceleration, more responsive handling, and improved braking. Furthermore, lightweight wheels often feature a more open design, which can aid in brake cooling during spirited driving or track sessions.
When selecting lightweight wheels, consider reputable brands such as BBS, Volk Racing, and Apex. These manufacturers offer high-quality forged or flow-formed wheels, which provide strength and weight savings without compromising on style. Be sure to choose the appropriate size, offset, and tire combination to maximize performance while maintaining a proper fitment on your E90.
Chassis Bracing
Strut braces
Installing strut braces on your E90 can enhance chassis rigidity, resulting in a more precise and responsive driving experience. Strut braces connect the tops of your vehicle’s strut towers, helping to reduce flex and improve the suspension’s effectiveness. This upgrade is particularly beneficial for spirited driving and track days, where a stiffer chassis can enhance cornering performance and provide a more connected feel.
Various aftermarket strut braces are available for the BMW E90, with top brands like Turner Motorsport, Dinan, and AC Schnitzer offering solutions designed to fit your vehicle perfectly. When selecting a strut brace, consider materials such as lightweight aluminum or carbon fiber, which offer strength and rigidity without adding unnecessary weight. Installation is generally straightforward, making this a popular and accessible upgrade for many enthusiasts.
Subframe reinforcements
The E90’s subframe, while robust, can benefit from reinforcement to further improve chassis rigidity and prevent potential stress-related failures. Subframe reinforcements help to strengthen key connection points between the chassis and suspension components, resulting in a more stable and predictable handling experience.
Subframe reinforcement typically involves welding or bolting reinforcement plates or bars to the existing chassis. This process can be labor-intensive and requires specialized tools and knowledge, so it’s best to consult with a professional or experienced enthusiast for guidance. Companies like Turner Motorsport and BimmerWorld offer reinforcement kits designed specifically for the E90, ensuring a proper fit and improved chassis strength.
Aerodynamic Improvements
Front splitters and rear diffusers
Enhanced downforce and stability: Aerodynamic modifications such as front splitters and rear diffusers can greatly improve the downforce and stability of your E90 at higher speeds. Front splitters help to redirect air around the sides of the vehicle, reducing lift and enhancing front-end grip. Rear diffusers, on the other hand, work to channel air from underneath the car, reducing drag and generating downforce. Both of these components contribute to a more planted and stable feel at high speeds, providing increased confidence during spirited driving or track sessions.
When selecting a front splitter or rear diffuser, consider options from reputable manufacturers such as Vorsteiner, 3D Design, or BMW’s own M Performance line. These companies offer a range of materials, including carbon fiber, ABS plastic, and aluminum, allowing you to choose the perfect balance of weight, strength, and aesthetics for your E90.
Side skirts and canards
Side skirts and canards are additional aerodynamic modifications that can enhance your E90’s performance and appearance. Side skirts help to manage airflow along the sides of the vehicle, reducing turbulence and drag, while canards create vortexes that increase downforce on the front end. Both of these components contribute to a more efficient and stable aerodynamic profile, improving handling and high-speed stability.
Installation and aesthetics: When selecting side skirts and canards, consider options that complement your E90’s existing design language while providing functional aerodynamic benefits. Companies like AC Schnitzer, RKP, and BMW M Performance offer a variety of styles and materials to suit your preferences. While installation is generally straightforward, it’s essential to ensure proper fitment and alignment to maximize the effectiveness of these components.
In Conclusion
In this article, we have explored the top chassis modifications for the BMW E90, including suspension upgrades, weight reduction, chassis bracing, and aerodynamic improvements. Each of these modifications plays a crucial role in enhancing your vehicle’s performance and driving experience, allowing you to tailor your E90 to your specific needs and preferences.
Chassis modification is a journey of personalization and the pursuit of automotive perfection. As you explore the world of upgrades, remember that the ideal setup is unique to each individual, reflecting their driving style, preferences, and goals. Take the time to research, consult with fellow enthusiasts, and test various modifications to create the perfect E90 that embodies your passion for the ultimate driving machine.
With this guide as your starting point, we encourage you to delve deeper into the world of chassis modification and discover the vast