Dinan Supplemental Ride Quality & Handling Kit – 2014–2020 BMW 340i / 428i / 430i / 435i / 440i (F30/F32/F36) | 4x Progressive-Rate Bump Stops | Tuned for Dinan Performance Springs

The Dinan Supplemental Ride Quality & Handling Kit for the 2014–2020 BMW 340i, 428i, 430i, 435i, and 440i (F30/F32/F36 chassis) is a set of four progressive-rate bump stops engineered to work in tandem with Dinan's Performance Spring Sets — maximizing suspension travel on the lowered vehicle, preventing bottoming out, and amplifying both handling performance and ride quality beyond what the spring set alone can achieve. This kit is the essential companion to Dinan's Performance Spring Set for these BMW platforms — Dinan strongly recommends purchasing and installing both together for correct ride height, ride quality, and handling performance.

Why the Handling Kit Is Essential:

When a vehicle is lowered with performance springs, the reduced ride height compresses the suspension's available travel. Without correctly tuned bump stops, the suspension can reach the end of its travel over sharp bumps or during hard cornering — causing a sudden, harsh "bottoming out" that is both uncomfortable and detrimental to handling. Dinan's progressive-rate bump stops solve this problem by providing a carefully tuned secondary spring rate as the suspension approaches full compression — allowing the suspension to use its full available travel progressively rather than hitting a hard stop. The result is a lowered vehicle that rides smoothly over bumps, maintains correct suspension travel, and delivers improved mechanical grip and cornering power compared to a spring-only installation.

Key Features:

• 4x progressive-rate bump stops — four bump stops (front and rear) made from OE-quality material with progressive rate characteristics — the bump stop rate increases progressively as the suspension compresses, providing a smooth transition rather than a sudden hard stop
• Tuned for Dinan springs — the bump stops are carefully tuned specifically for use with Dinan's Performance Spring Sets — the progressive rate is calibrated to complement Dinan's spring rates for the correct balance of ride quality and handling performance
• Maximizes suspension travel — by allowing full compression travel within the spring, the bump stops prevent the sudden bottoming out that is a common side effect of lowering a vehicle without correctly tuned bump stops
• Improved mechanical grip — correctly tuned bump stops optimize the effective spring rate through the full range of suspension travel — rewarding drivers with added mechanical grip and cornering power
• OE quality material — bump stops are manufactured from OE-quality material for progressive characteristics and long-term durability — correct material specification for the F30/F32/F36 suspension environment
• Amplifies spring set performance — the handling kit amplifies both performance and comfort when paired with Dinan's Performance Spring Set — the complete Dinan suspension system delivers results that neither component achieves alone

Progressive Bump Stops — How They Work:

A bump stop is a rubber or polyurethane component that sits between the suspension's upper mount and the shock absorber body. As the suspension compresses toward full travel, the bump stop contacts the shock body and begins to provide an additional spring rate — slowing the suspension's compression rate and preventing a hard bottom-out. A progressive-rate bump stop increases its rate as it compresses further — providing a gentle initial contact that becomes progressively firmer as the suspension approaches full compression. This progressive characteristic is what allows Dinan's system to maintain ride quality while preventing bottoming out — the transition from spring rate to bump stop rate is smooth and controlled rather than sudden and harsh.

Specifications:

• Brand: Dinan
• Part Number: dnnD193-3201
• Barcode: D193-3201
• Contents: 4x progressive-rate bump stops
• Material: OE-quality progressive-rate material
• Application: 2014–2020 BMW 340i / 428i / 430i / 435i / 440i — F30 / F32 / F36

Fitment Information:

• 2016–2018 BMW 340i — F30 sedan — B58
• 2014–2016 BMW 428i — F32 coupé / F36 Gran Coupé — N20/N26
• 2017–2020 BMW 430i — F32 coupé / F36 Gran Coupé — B48
• 2014–2016 BMW 435i — F32 coupé / F36 Gran Coupé — N55
• 2017–2020 BMW 440i — F32 coupé / F36 Gran Coupé — B58
• Verify your specific BMW model, year, and chassis code before ordering — confirm that dnnD193-3201 is the correct handling kit for your specific vehicle and the corresponding Dinan spring set
• Note: This kit is designed for use with the corresponding Dinan Performance Spring Set. Installing without Dinan springs may not provide the intended results. Professional installation by an experienced BMW suspension specialist strongly recommended.

What's Included:

• 4x Dinan progressive-rate bump stops — 2014–2020 BMW 340i/428i/430i/435i/440i F30/F32/F36 (dnnD193-3201)
• Refer to Dinan's product documentation for complete kit contents and installation instructions

Installation Notes:

• Professional installation by an experienced BMW suspension specialist strongly recommended — bump stop installation requires correct spring compressor tools and correct reassembly of the strut/shock assembly
• Install simultaneously with the Dinan Performance Spring Set for correct results — the bump stops and springs are designed to work together as a system
• A four-wheel alignment is required after suspension installation — do not drive at speed before alignment is performed

Why Dinan?

Dinan is the most respected BMW performance tuning brand in North America — an American company with decades of BMW-specific engineering experience. Dinan's suspension systems are engineered as a complete system — the Performance Spring Set and Supplemental Ride Quality & Handling Kit work together to deliver the correct balance of lowered ride height, increased spring stiffness, and maintained suspension travel that defines the Dinan suspension experience. For F30/F32/F36 owners who want the complete Dinan suspension system with correctly tuned progressive bump stops, dnnD193-3201 is the correct companion kit to the Dinan Performance Spring Set.

Perfect For:

• 2014–2020 BMW 340i, 428i, 430i, 435i, and 440i (F30/F32/F36) owners installing the Dinan Performance Spring Set who need the corresponding Supplemental Ride Quality & Handling Kit for correct suspension travel, ride quality, and handling performance
• F30/F32/F36 owners who want the complete Dinan suspension system — progressive-rate bump stops tuned specifically for Dinan springs that maximize suspension travel, prevent bottoming out, and amplify mechanical grip and cornering power

Note: Designed for use with the corresponding Dinan Performance Spring Set — install both together for correct results. Verify BMW model, year, and chassis code before ordering. Four-wheel alignment required after installation. Professional BMW suspension specialist installation strongly recommended.