Ultra Racing Underbody Brace Kit (Lower Chassis/Tunnel/Subframe) for BMW F2x 1 Series F20 F21 & 2 Series F22 – M135i M140i M235i M240i – Chassis Stiffening Undercarriage/Belly

Transform the way your F2x drives with this Ultra Racing lower chassis brace kit. Designed for the BMW F-series 1 and 2 platform, this underfloor bracing upgrade increases chassis rigidity, reduces flex and delivers sharper steering feel and improved stability on fast road and track. A true bolt-on handling upgrade that fits beautifully and comes with all the necessary fixings. Part number: ULTRA-RL-3885.

Engineered for the F20 and F21 1 Series and the F22 2 Series, including M135i, M140i, M235i and M240i. Not suitable for convertible models. The profile sits a touch lower to clear freer-flowing exhaust systems, making it a brilliant choice for cars with aftermarket cat-back or performance exhausts.

• Lower chassis brace, tunnel brace, subframe reinforcement bar and undercarriage brace for the F2x platform
• Improves torsional rigidity for crisper turn-in and more precise handling
• Direct bolt-on, uses supplied hardware with no extra parts required
• Compatible with performance exhaust upgrades thanks to its lower profile
• Ideal for fast road, track day and spirited driving

We use this brace on our own cars and customer builds and feedback has been outstanding. Drivers report tighter front-end response, greater confidence through corners and a more composed feel over rough surfaces. It is a simple, high-impact modification that complements springs, dampers, anti-roll bars and alignment changes.

What you get in the kit

• ULTRA-RL-3885 - Under body brace
• 33326793651 - Pushrod left
• 33326793652 - Pushrod right
• 33306861221 - Torx bolt x2
• 51118174185 - Expanding plastic rivet x2
• 07147201307 - White plastic parts x2

Fitment and compatibility

• BMW 1 Series F20 and F21, including M135i 2012+ and M140i 2015+
• BMW 2 Series F22, including M235i and M240i
• All models on the F2x platform except cabriolet

Why buy this handling upgrade

• Chassis bracing that targets underbody flex for a more planted feel
• Perfect complement to suspension and wheel upgrades
• Precise fitment for F2x with OEM-style hardware included
• Enhances road holding without compromising everyday usability

Fitting service

Professional installation available at MJ Modifications in Warwickshire. To book fitment or request a quote, email info@mjmodifications.co.uk.

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