Installing JDM coilovers is one of the most rewarding upgrades you can make to your car. This step-by-step guide covers how to install Tein, BC Racing, and KW coilovers on most JDM platforms — with tips that apply whether you're working on a Nissan Silvia, Honda Civic, Subaru WRX, Mitsubishi Evo, or Toyota Supra.

Tools You Need for Coilover Installation

• Floor jack and axle stands (minimum 2-tonne rating)
• Spring compressor (essential — do not attempt without one)
• Socket set: 10mm, 12mm, 14mm, 17mm, 19mm, 21mm
• Torque wrench (0–150 Nm range)
• Pry bar or ball joint separator
• Penetrating oil (PB Blaster or WD-40 Specialist)
• Thread lock (Loctite Blue 243)
• Alignment string or access to a wheel alignment shop

Step 1: Preparation and Safety

Park on level ground. Loosen wheel bolts before jacking up the car. Apply penetrating oil to all suspension bolts — strut top mounts, lower control arm bolts, sway bar end links — at least 30 minutes before you start. Rusty hardware is the most common cause of installation problems. Always use axle stands — never work under a car supported only by a floor jack.

Step 2: Remove the Front Struts

Working one side at a time: remove the wheel. Disconnect the sway bar end link from the strut (usually 17mm). Remove the brake line bracket from the strut (usually 10mm bolt). Disconnect the ABS sensor wire from the strut if fitted. Remove the two lower strut-to-hub bolts (usually 17mm or 19mm). These are often tight — use a breaker bar. Finally, go into the engine bay and remove the three strut top mount bolts (usually 12mm). The strut assembly will drop free. Support it while removing — it's heavy.

Step 3: Disassemble the Stock Strut

Use a spring compressor to compress the stock spring before removing the top mount nut. This is critical for safety — never remove the top nut without compressing the spring. Once the spring is compressed and the top nut removed, disassemble the strut. Keep the top mount and bearing — many coilover kits reuse the OEM top mount, particularly Tein and BC Racing. KW kits typically supply their own top mounts.

Step 4: Assemble Your New Coilovers

Tein Flex Z / Street Basis: Attach the OEM top mount (or supplied top mount) to the coilover. Set ride height before installation by adjusting the lower collar using the provided spanner wrench. Tein coilovers adjust ride height by changing the distance between the lower mount and spring seat. Set both sides to the same measurement before installation.

BC Racing BR Series: BC Racing coilovers have separate ride height and spring preload adjustment. Ride height is set using the lower collar (spanner wrench required). Damping is adjusted using the knob at the top of the shock body — 30 clicks from full soft. Start at 10-15 clicks from full soft for street use.

KW Variant 3: KW coilovers come with their own top mounts for most applications. Attach the top mount to the coilover body per the KW instruction manual. The Variant 3 has separate high-speed and low-speed damping adjusters at the top of the shock. Start at the recommended settings in the KW manual for your car.

Step 5: Install Front Coilovers

Feed the assembled coilover up through the wheel arch and into the strut tower. Start the three top mount bolts by hand before tightening. Align the lower mount with the hub bracket and insert the lower bolts. Torque to manufacturer specification: typically 100–120 Nm for lower strut bolts, 25–35 Nm for top mount bolts. Reconnect sway bar end links, ABS sensor, and brake line bracket. Refit wheel and torque bolts to 100 Nm. Repeat for the other front corner.

Step 6: Remove and Install Rear Suspension

Rear suspension varies significantly by car. For MacPherson strut rear (most JDM hatchbacks and coupes): the process mirrors the front. For multi-link rear (Skyline, Evo, WRX STI): you may need to remove the rear subframe bolts or unbolt lower control arms to access the rear struts. Consult your specific vehicle service manual for rear suspension disassembly on complex multi-link setups.

Step 7: Set Initial Ride Height and Damping

For street use, aim for 20–35mm lower than stock as a starting point. This provides improved handling without sacrificing too much suspension travel. Set front and rear damping to the middle of the adjustment range initially, then refine after driving. Critical: after installation, bounce each corner of the car several times and recheck that all bolts are torqued correctly before driving.

Step 8: Wheel Alignment — Do Not Skip This

After coilover installation, a professional wheel alignment is mandatory. Lowering changes camber, toe, and sometimes caster. Driving on misaligned wheels causes rapid tyre wear, unstable handling, and can be dangerous. Specify your target camber and toe settings when booking alignment — for street use, -1.5 to -2.0 degrees front camber is a good starting point for most JDM platforms.

Buy Genuine JDM Coilovers — Worldwide Shipping

At Grovexo JDM, we supply 100% authentic Tein, BC Racing, KW, and Cusco coilovers with worldwide shipping. Every kit comes with full installation instructions and manufacturer support. Search keywords: tein coilover install, bc racing coilover installation guide, KW coilover setup, how to fit coilovers, JDM suspension installation, coilover fitting guide, tein flex z installation, BC BR series install.