If you're looking to transform your Nissan 240SX into a precision handling machine, upgrading the suspension is the single most impactful modification you can make. The S13, S14, and S15 chassis are legendary for their balanced front-engine, rear-wheel-drive layout, but they are now over two decades old. Factory bushings have hardened, shocks are worn, and the original geometry was never designed for modern sticky tires or track-day aggression. By addressing the suspension systematically, you can dramatically improve grip, stability, steering feel, and overall confidence behind the wheel. Below we break down the ten most effective 240SX suspension upgrades, from basic bolt-ons to advanced geometry corrections, all designed to make your car handle like it was born for the circuit.

1. Coilover Suspension Kits

Coilover kits replace the entire spring-and-shock assembly with a single, height-adjustable unit. This allows you to lower the car’s center of gravity, dramatically reducing body roll and weight transfer during cornering. Most modern coilovers for the 240SX also feature adjustable damping (rebound and compression), letting you dial in stiffness for street cruising or track attack.

When comparing coilovers, pay attention to spring rates, damper technology (twin-tube vs. monotube), and whether the kit offers front camber plates (which we'll cover separately). Entry-level options like the Fortune Auto 500 Series provide excellent value, while setups from BC Racing, Tein, and KW offer everything from daily comfort to full-race aggression. Installing coilovers also gives you access to corner-weighting—critical for balanced handling. Expect a transformative change in steering response and chassis composure, but be prepared for a firmer ride on rough roads.

For the 240SX, consider the S13/S14 bolt-in variants that preserve rear shock tower clearance. Adjustable lower mounts allow perch height adjustment without compressing the spring, maintaining full shock travel. No other single upgrade will amplify your car's potential as dramatically as a quality coilover system.

2. Upgraded Sway Bars

Sway bars (anti-roll bars) connect the left and right suspension arms to control body lean during cornering. Factory 240SX bars are thin and flexible, allowing significant roll that hinders tire contact patch loading. Upgrading to a thicker (usually hollow) aftermarket sway bar stiffens the chassis in roll, reducing body lean and keeping both inside and outside tires more evenly planted.

Many enthusiasts start with a rear sway bar upgrade to induce a mild oversteer tendency, while a larger front bar understeers. Balancing the two is key. Popular brands like Whiteline and Progress offer adjustable sway bars that allow multiple mounting points to fine-tune stiffness. For street-driven cars, a 24mm front and 22mm rear combination works well. Also upgrade the sway bar end links to solid, adjustable units—this eliminates slop from worn rubber joints.

Installation is straightforward and can be done at home with basic hand tools. Pair sway bars with upgraded bushings for the full benefit. The reduction in roll will allow your coilovers or springs to work more effectively, giving you a stable platform for aggressive cornering.

3. Performance Shock Absorbers

If you're not ready for full coilovers but still want improved damping, performance shock absorbers (or struts) are an excellent intermediate upgrade. Shock absorbers control the oscillation of the springs—keeping the tire in contact with the road surface during bumps and weight transfer. Factory shocks are tuned for comfort and fade quickly under prolonged stress.

Aftermarket options like Koni Yellows, Tokico Illuminas, or KYB AGX offer adjustable damping rates. Koni Sport shocks (yellow) have a lifetime warranty and are rebuildable, making them a favorite for budget-oriented track builds. For the 240SX, a common setup is pairing adjustable shocks with lowering springs (which we cover later) for a marked improvement without the cost of coilovers.

Performance shocks are essential for any car that sees track days or aggressive canyon driving. They reduce pitch under braking, squat under acceleration, and keep the tires planted through transitions. If you have a stock suspension that feels floaty, this upgrade alone will tighten the ride significantly.

4. Strut Braces

Nissan's S-chassis unibody is known to flex over time, particularly between the front strut towers. A strut brace (or tower bar) ties the two strut tops together, triangulating the front chassis. This reduces flex when the front suspension loads during cornering, sharpening steering response and providing a more direct feel through the wheel.

Choose between solid aluminum braces (like Cusco or Carbing) for maximum stiffness, or lighter/lower-profile options if you need hood clearance. Some braces include a master cylinder stopper to reduce firewall flex, improving brake pedal feel. Rear strut braces also exist for the 240SX, but the front is where the biggest gains are felt. This is a simple, low-cost modification that returns big dividends in chassis rigidity.

Strut braces don't replace structural upgrades like roll cages or seam welding, but they are a great first step. Pair with subframe collars (see #9) for a more comprehensive chassis stiffening package.

5. Adjustable Control Arms

Once you lower your 240SX with coilovers or springs, the suspension geometry shifts—often causing bump steer and poor camber curves. Adjustable control arms correct these issues. Front tension rods, rear upper and lower control arms, and toe arms allow precise alignment settings that maintain suspension performance at lowered heights.

For the front, adjustable tension rods replace the stock rubber-bushed arms with spherical bearings and threaded adjusters. This allows caster adjustment, which improves straight-line stability and steering self-centering. In the rear, adjustable camber arms and toe arms let you set the wheels to the correct angle for even tire wear and maximum grip while cornering.

Brands like GKTech and Parts Shop Max offer complete arms with fully sealed spherical bearings that last for years. This upgrade is virtually mandatory for any 240SX lowered more than 1.5 inches. Expect to need a proper alignment after installation— a four-wheel alignment specialist familiar with the S-chassis is essential.

6. Upgraded Bushings

Rubber suspension bushings are designed for comfort and noise isolation, but they allow significant deflection under load. As they age, they harden, crack, and become sloppy. Replacing them with polyurethane or solid spherical bearings (heim joints) transforms how the suspension responds. Every input from the steering wheel is transmitted directly, and the car tracks more accurately over bumps.

Focus on the front tension rod bushings, rear subframe bushings, and rear knuckle bushings for the biggest returns. Polyurethane bushing kits (from Energy Suspension, Whiteline, or Super Pro) can be pressed in at home with patience and a press. For race-only cars, solid aluminum or Delrin bushings eliminate all deflection, but they increase harshness. A popular compromise is using polyurethane in the subframe and front arms, and replacing rear knuckle bushings with sealed spherical units.

After replacing bushings, the suspension feels like new—tighter, more predictable, and far more communicative. It's a foundational upgrade that amplifies the effectiveness of all other suspension components.

7. Camber Kits

Camber refers to the vertical tilt of the wheels relative to the road surface. Negative camber (top of tire tipped inward) improves grip during cornering by maximizing the tire contact patch under load. However, too much negative camber wears tires unevenly and reduces straight-line braking. A camber kit allows you to adjust front and rear camber independently from the ride height.

Front camber plates replace the stock strut top mounts and provide a range of adjustment. Most coilover kits come with camber plates included, but they can be purchased as an add-on. In the rear, the 240SX's multi-link suspension allows camber adjustment via eccentric bolts or adjustable upper arms (see #5).

For street use, -1.5° to -2.5° of negative camber in front and -1.0° to -2.0° in the rear is typical. Track cars often run more aggressive numbers. Having the ability to dial in camber per track day ensures you can balance tire temp and wear. It's a small investment that unlocks the true handling potential of sticky tires.

8. Lowering Springs

Lowering springs are a budget-friendly way to lower ride height, reduce the center of gravity, and tighten body roll. They work by compressing the suspension further with a shorter, stiffer spring. Most lowering springs for the 240SX drop the car 1.2–1.5 inches. Pair them with performance shocks (see #3) for proper damping; otherwise, the ride quality suffers due to the mismatch with worn factory dampers.

Popular options include Eibach Pro-Kit, Tein S.Tech, and Swift Spec R springs. Each offers a different spring rate and drop. Lowering springs are a great starting point if you're on a tight budget, but they don't offer adjustability. If you plan to track the car seriously, coilovers are ultimately a better long-term choice. However, a set of lowering springs with new shocks can still transform handling for spirited street driving.

Installation requires safe jacking and spring compressor tools; if you're not comfortable, a professional installation is recommended. Always get an alignment after lowering.

9. Rear Subframe Collars

The rear subframe of the 240SX bolts to the unibody via large rubber bushings that allow movement. Under hard acceleration or cornering loads, the subframe can shift, causing rear-end instability and vague handling. Rear subframe collars (or solid subframe bushings) eliminate that movement. The collars are urethane or aluminum inserts that fill the void in the subframe bushing cavities without removing the stock bushings.

Installation is straightforward: raise the rear of the car, loosen the subframe bolts, slide the collars into place, and retighten. This firms up the rear of the car instantly, giving you a planted feel during high-speed cornering and traction events. Power output also benefits because the differential is more rigidly located, reducing wheel hop.

Combined with upgraded subframe bushings (solid or poly), this upgrade dramatically improves stability. Many drifters cite subframe collars as a must-have for predictable slides. For road racers, they transform rear-end confidence in sweepers and chicanes.

10. Lightweight Wheels

Suspension upgrades are only as effective as the wheels that carry the tires. Lightweight wheels reduce unsprung mass—the weight not supported by the suspension. Less unsprung weight allows the suspension to react faster to bumps, improving tire contact patch consistency. The 240SX's original 15-inch or 16-inch alloy wheels are heavy by modern standards. Swapping to a forged or flow-formed wheel in 17x9 specifications cuts several pounds per corner.

Quality lightweight wheels like Enkei RPF1s, Rays Gram Lights, or WedsSport wheels also improve steering response and acceleration because the engine has less rotational inertia to overcome. Combined with sticky tires, the entire handling package comes alive. Aim for wheels that maintain the correct offset to avoid rubbing and to preserve the scrub radius.

Don't forget to use hub-centric rings if the wheels aren't exact fit. Lightweight wheels are the finishing touch to a suspension build, allowing all other components to work optimally. The change in feel is immediate and addictive.

Conclusion

Building a suspension package for your Nissan 240SX is about layering improvements that work together. Start with the foundation: bushings, shocks, and height adjustability. Then move to geometry corrections with arms and camber kits. Finally, stiffen the chassis with strut braces and subframe collars. Round it off with lightweight wheels and sticky tires for the ultimate grip. Each of these ten upgrades contributes to a more connected, stable, and predictable driving experience, whether you're chasing lap times or carving mountain roads.

Remember that proper alignment and corner balancing are critical to realizing the full potential of your components. Seek out shops experienced with the S-chassis, and don't be afraid to experiment with settings. The 240SX rewards those who take the time to fine-tune. With the right suspension upgrades, you'll unlock a level of handling that rivals modern sports cars—proving that this icon is still one of the best driver's cars ever built.