Tein 11-16 Hyundai Genesis Coupe BK14 Street Basis Z Coilovers

Lower Your Genesis Coupe Without Sacrificing the Daily Drive

The Tein GSF12-8UAS2 Street Basis Z Coilover Kit transforms the handling and stance of the 2010-2016 Hyundai Genesis Coupe BK14 without turning it into a punishment on rough roads. Built around Tein's proven twin-tube damper architecture, this kit delivers a lowered, planted ride that works just as well on the morning commute as it does on your favorite back road.

Key Features

• Twin-tube internal construction provides longer stroke and reduced repulsive force versus mono-tube designs for superior ride comfort at a lowered stance
• Thread-type ride height adjustment via lower spring seat lets you dial in stance corner by corner
• Steel construction with powder-coated damper body and non-welded ZT-coated adjustment tube for heavy-duty corrosion resistance
• Anodized brackets with Teflon-coated shock body for long-term durability in all weather conditions
• Utilizes OEM upper mounts, keeping upgrade cost down while maintaining factory geometry
• No-sag springs engineered specifically for the Genesis Coupe BK14 chassis at Tein's recommended lowering range
• 1-piece aluminum spring seat with Delrin thrust washer for smooth, precise height adjustments
• Full-length dust boots included (some configurations reuse OEM dust boots)
• Front lowering range: -0.4 in. to -2.6 in. (10mm to 67mm) depending on engine and model year
• Rear lowering range: -0.6 in. to -2.7 in. (15mm to 69mm) depending on trim
• Front spring rate: 336 lbs/in (6.0 kgf/mm), Free length: 215mm
• Rear spring rate: 336 lbs/in (6.0 kgf/mm), Free length: 226mm

Fitment

Important Note: For 2011-2016 model years, the OE front sway bar link rod from the 2010 model (or Tein sway bar link rod SPS23-R5916) is required. Without it, the sway bar cannot be installed to the damper.

Specifications

What's Included

• 4 Tein Street Basis Z coilover shock assemblies
• 4 Tein no-sag coilover springs
• 4 rubber bump stops
• 4 spring seats
• 4 spring locks
• 4 Delrin thrust washers
• 4 dust covers (some kits reuse OEM dust covers)
• 2 hook spanners
• 1 Tein sticker sheet
• 1 instruction manual

About Tein

Founded in Japan in 1985, Tein Suspension Technology has built its reputation on precision-engineered suspension components developed through decades of motorsport competition. Every Tein product begins on the track and is refined for the street, resulting in coilovers that balance performance, comfort, and durability for real-world driving. The GSF12-8UAS2 Street Basis Z represents Tein's commitment to making premium height-adjustable suspension accessible without cutting corners on materials or manufacturing.

FAQ

The GSF12-8UAS2 fits the 2010-2016 Hyundai Genesis Coupe BK14 in both the 2.0T and 3.8 engine configurations across all named trims including 2.0T, 2.0T Premium, 2.0T R-Spec, 2.0T Track, 3.8, 3.8 Grand Touring, 3.8 R-Spec, 3.8 Track, and 3.8 Ultimate.

No. The Tein Street Basis Z is designed to reuse your factory OEM upper mounts. They are not included in the kit. This is a deliberate design choice that reduces cost and preserves factory steering geometry.

Yes, the GSF12-8UAS2 fits 2010 Genesis Coupe models in all engine configurations. However, note that the 2010 model uses a different front sway bar link rod connection point. For 2011-2016 installations, the OE 2010 front sway bar link rod or the Tein replacement link rod (SPS23-R5916) must be used, otherwise the front sway bar cannot attach to the damper.

The front lowering range is approximately 0.4 in. to 2.6 in. (10mm to 67mm) below stock ride height depending on your engine variant. The rear range is 0.6 in. to 2.7 in. (15mm to 69mm). Adjustment is made by moving the lower spring seat up or down along the threaded shock body.

No. The GSF12-8UAS2 Street Basis Z is a ride-height-adjustable coilover only. Damping force is fixed and non-adjustable. If you need compression and rebound damping adjustment, Tein's Street Advance Z or Flex Z series would be the appropriate upgrade.

Both front and rear springs are rated at 336 lbs/in (6.0 kgf/mm). The front spring free length is 215mm and the rear is 226mm. Tein selects these rates specifically to complement the twin-tube damper valving for a balanced daily-driver ride quality at lowered heights.

Yes. Any coilover installation that changes ride height will alter your camber and toe settings. A professional four-wheel alignment is required after installation and again after your first 500 miles as suspension components fully seat. Skipping alignment will cause accelerated tire wear.

The GSF12-8UAS2 does not carry a CARB exemption. If you are registering your vehicle in California, check current CARB regulations regarding coilover installation on your specific model year. The product is tagged Non-CARB:N in our system. Prop 65 does not apply to this product based on manufacturer data.

The twin-tube design used in the GSF12-8UAS2 produces a longer effective damper stroke within a shorter overall unit length compared to mono-tube designs. This gives the shock more travel at lowered heights, which translates to better small-bump absorption and a more compliant daily-driver feel. Mono-tube designs prioritize heat dissipation for track use; twin-tube designs prioritize comfort and stroke efficiency for street use.

Yes. Tein offers rebuild and revalve services through their US service center. Replacement springs, bump stops, and hardware are also available separately. This makes the GSF12-8UAS2 a long-term investment rather than a disposable coilover kit.

Installation Instructions

1. Safely lift the vehicle and support on jack stands at all four corners. Remove wheels.
2. Disconnect the OEM sway bar end links from the factory struts at the front axle. If installing on a 2011-2016 model, set the 2010 OEM front end link aside to reinstall on the new damper, or use Tein link rod SPS23-R5916.
3. Disconnect the ABS sensor harness and brake line bracket from the OEM front strut. Remove the three top hat nuts from the strut tower.
4. Compress the OEM front spring if needed to extract the strut assembly. Remove the top hat (OEM upper mount) and retain it for reinstallation.
5. Assemble the front Tein coilover unit. Thread the spring seat to your desired starting ride height position. Install the OEM top hat onto the Tein strut using the supplied hardware.
6. Reinstall the assembled front coilover into the strut tower, torque the top hat nuts to OEM specification, then reconnect the ABS harness, brake bracket, and sway bar end link.
7. For the rear, disconnect the OEM shock from its upper and lower mounting points. Retain the OEM upper mount hardware.
8. Assemble the rear Tein coilover at your desired starting height, reinstall using OEM upper mount hardware, and torque all fasteners to specification.
9. Reinstall all wheels and lower the vehicle. Bounce each corner several times to allow suspension to settle.
10. Road test at low speed and confirm no rubbing or clearance issues before driving normally.
11. Schedule a professional four-wheel alignment immediately after installation. Re-torque all fasteners after the first 500 miles.