Superpro Radius Arm To Chassis Mount Bush Kit - Caster Adjustable SPF4306K - F20, F21 1 Series

SuperPro Front Lower Control Arm Rear Bush Set with Caster Adjustment – BMW 1 Series F20 F21

Transform the front end feel of your BMW 1 Series with this precision engineered SuperPro upgrade. This caster adjustable poly bush kit sharpens steering response, improves straight line stability and helps you dial in alignment for confident road driving and track work. We run these on our own cars at MJ Modifications and customer feedback has been outstanding for steering feel, bite on turn in and overall handling balance.

Perfect for enthusiasts who want a durable, performance focused front suspension upgrade for the F20 and F21 chassis, these bushes allow on car caster adjustment for easy alignment correction without removing the arm.

Key features

• On car caster adjustment for precise front end geometry
• Crisper steering input and improved stability under braking
• Enhanced road feel with reduced deflection compared to tired factory mounts
• Ideal handling upgrade for fast road and track day setups
• Direct replacement performance bushings for the front tension strut to body position

Fitment and technical notes

• Chassis: BMW 1 Series F20 and F21 rear wheel drive
• Fits housings with 70 mm outside diameter and 95 mm tube length
• Does not suit xDrive models that use an 80 mm length hydro bearing
• Quantity in kit: 2 bushes

Part numbers

• SuperPro reference: SPF4306K
• Replaces BMW OE: 31 12 6 855 743

Why upgrade your front bushings

• Restore accurate alignment and reduce unwanted movement at the front wishbone rear mount
• Better tyre contact patch for improved grip and confidence
• Helps reduce tramlining and improves feedback through the wheel

Compatibility keywords for searches

BMW F20 suspension bushes, BMW F21 poly bushes, front wishbone rear bush, tension strut mount, front control arm rear bushing kit, caster adjustable bushings, alignment correction kit, performance suspension upgrade, BMW 1 Series handling upgrade, polyurethane bush set.

Professional fitting available

Want it installed correctly first time? Book fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a quote and availability.