KW Variant 3 (V3) inox-line Coilovers for BMW 1 Series M135i/M140i (F20/F21) 2WD with Electronic Dampers - Height Adjustable, Independent Rebound & Compression Damping (Chassis 1K2, 1K4)

Unlock precision handling, lower stance and everyday comfort with this premium stainless steel adjustable suspension kit for the BMW 1 Series F20 and F21 two wheel drive M135i and M140i models with factory electronic dampers, chassis codes 1K2 and 1K4. This is the go to fast road and track day upgrade for drivers who want proper body control, real ride quality and fine tuning freedom.

Performance upgrade that transforms your 1 Series

• Independent damping control with 16 step rebound and 12 step compression for genuine chassis tuning
• Inox stainless struts and bodies for corrosion resistance on British roads and winter salt
• Continuous ride height adjustment to dial in stance, balance and weight distribution
• Twin tube damper architecture developed on road, motorway and the Nürburgring for control and compliance
• High quality components, precise adjusters and clear documentation for easy setup

Lowering range and axle loads

• Front drop range: 25 to 50 mm
• Rear drop range: 30 to 55 mm
• Maximum permitted axle load in kg: Front 921 to 1090, Rear up to 1230

Vehicle compatibility

• BMW 1 Series M135i and M140i
• F20 and F21 chassis
• Rear wheel drive
• For vehicles equipped with electronic dampers
• Chassis codes 1K2 and 1K4

Why enthusiasts choose this kit

Independent rebound and compression lets you tailor the balance to your driving. Soften rebound for comfort on rough B roads or add a few clicks for sharper body control. Increase compression to improve turn in, reduce roll and unlock traction out of corners while keeping ride quality. The result is stability at speed, confidence on turn in and a compliant ride that works with UK tarmac.

Built to last

Stainless steel inox line construction, dirt resistant trapezoid threads and composite spring seats mean smooth height adjustment year after year. Every damper is validated on the rig and proven in real world testing so you get consistent performance across road, fast road and track day use.

Real world results

We run this setup on our own builds and customer cars, and feedback is consistently positive on steering precision, mid corner grip and daily comfort. The adjustability makes it simple to set a fast road baseline, then add a few clicks for a circuit day and drive home in comfort.

Key highlights at a glance

• Height adjustable suspension kit for front and rear
• 16 click rebound and 12 click compression for independent damping control
• Stainless construction for rust free durability
• Continuous lowering within a tested range
• High quality hardware and clear instructions

Quality and warranty

Every kit undergoes stringent quality control. When installed by an approved specialist, warranty coverage can be up to five years on this inox line setup.

Professional fitting and setup

For installation, corner weighting and a fast road or track day setup, book with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a fitting quote and initial damping recommendations tailored to your use.

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