Name: CSF High-Performance Auxiliary Radiators for Fxx BMW 340i, 430i, 440i, M140i, M2, and M240i [8355]
Brand: CSF
SKU: 8355
Price: 389.00 USD
Availability: InStock

Description

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BP PRICING DIFFERENCE

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Description

CSF High-Performance Auxiliary Radiators for Fxx BMW 340i, 430i, 440i, M140i, M2, and M240i [8355]

CSF has earned an industry-leading reputation in BMW cooling, becoming the top choice for the B58 platform. As Gen-1 B58 vehicles continue to surge in popularity within the tuning community, demand for robust thermal solutions has grown accordingly. In response, CSF introduces High-Performance Auxiliary Radiators for the F87 M2 (N55), F3x 340i / 440i, and F2x M240i / M140i. Designed as complementary upgrades to CSF’s established F87 (N55) and F3x / F2x Cooling Suites, these auxiliary radiators address the limitations of factory systems that emerge under increased power and sustained aggressive driving. For owners pushing the capabilities of their M2s and first-generation B58 cars, CSF delivers the added cooling headroom required to keep performance consistent and temperatures in check.

Design & Engineering

CSF engineers the auxiliary radiators as a true drop-in fit for both left and right sides. Each unit mounts in the factory location with OEM quick connections and works in concert with the rest of the cooling system to lower temperatures, maintain optimal operating ranges, and extend resistance to heat soak — reducing the likelihood of track sessions cut short for cooldown laps.

OEM vs CSF

Compared to the OEM coolers, the CSF units represent a substantial upgrade. TIG-welded aluminum tanks are significantly larger than the OE plastic tanks for superior strength and increased fluid volume. A larger 2-row, 42 mm high-efficiency core employs CSF’s exclusive B-Tube technology and the latest 5 mm fin design to maximize airflow, heat rejection, and recovery while preserving flow. With many motorsport programs and enthusiasts pushing 700+ horsepower, the B58 is seeing coolant temperatures rise beyond safe limits—conditions that can trigger limp mode. CSF provides the thermal headroom to keep the B58 performing at its peak.

Construction

A 100% all-aluminum build ensures performance and durability. The integrated mounting frame is markedly stronger than the OE plastic pod system, while a black finish adds protection and corrosion resistance. For added security, CSF integrates bolt-on rock guards to shield the cores from debris — mitigating the punctures and fluid loss that have plagued OEM coolers and enhancing confidence on road or track.

Features

Multi-fit – fits both left & right side
2-row – 42mm high-performance core featuring CSF’s exclusive B-tube technology
New 5mm tall ultra efficient fins with a multi-louvered design for maximum surface area contact
Tank volume and core size increased
100% all-aluminum TIG-welded construction
OEM-style “quick connect” inlet / outlet
True “drop-in fit” requires no modifications to install
Includes detachable rock guard
Individually leak and pressure tested
High-performance upgrade suitable for professional racing, street performance, or OEM replacement
Satin black finish for OEM+ look
2 year limited warranty

Specifications

Core Thickness:
- CSF: 42mm
- OEM: 27.5mm
Core Rows:
- CSF: 2
- OEM: 1
Fin Height:
- CSF: 5mm
- OEM: 5mm
Tank Material:
- CSF: All-aluminum
- OEM: Plastic
Construction:
- CSF: 100% TIG-welded
- OEM: Crimp-on gasket

Applications

BMW 340i: F30, F31, F34 (2015-2019) [3.0L I6 Turbo B58]
BMW 430i: F32, F33, F36 (2016-2019) [2.0L I4 Turbo B48]
BMW 440i: F32, F33, F36 (2016-2019) [3.0L I6 Turbo B58]
BMW M140i: F20, F21 (2016-2019) [3.0L I6 Turbo B58]
BMW M2: F87 (2016-2018) [3.0L I6 Turbo N55]
BMW M240i: F22, F23 (2016-2021) [3.0L I6 Turbo B58]

Notes

Certain F3x 340i / 440i and F2x M240i / M140i models were not equipped with dual auxiliary radiators from the factory. Confirm the number of coolers on your BMW with a VIN lookup before ordering.
There were three auxiliary radiators used on 340i / 440i and M240i / M140i models. CSF #8355 is a direct drop-in replacement for BMW #17-11-8-625-447. It can also replace #17-11-7-628-057 and #17-11-7-600-697 when the appropriate mounting bracket(s) are used. Vehicles not originally equipped with #17-11-8-625-447 may require minor trimming of the air ducting for proper fitment. Models with the M Sport Package and M Sport Brakes typically use #17-11-8-625-447; verify via VIN with your dealership.
The upper brackets are identical across all three auxiliary radiator variants. Separate frames (cradles) aren’t needed, as CSF #8355 integrates the frame (BMW #17-21-8-625-445) into the cooler design.
Not compatible with the F87 M2 Competition, which uses S55 auxiliary radiators. On the F87 M2 with the N55, a single CSF #8355 auxiliary radiator mounts on the left-hand side. The right-hand side uses the CSF #8104 Race-Spec engine oil cooler.

About CSF

The Racing & High Performance Division of CSF Inc. is dedicated to designing and producing the world’s most advanced, efficient, and dependable cooling solutions. CSF offers a broad range of state-of-the-art cooling systems, with over 250 distinct applications. These include high-performance all-aluminum direct-fit radiators, intercoolers, and oil coolers, as well as bespoke manufacturing tailored for racecars, power sports, off-road vehicles, marine, and industrial applications. Every cooling solution from CSF is meticulously crafted to ensure optimal engine temperature management, even in the most rigorous driving scenarios. With a legacy spanning over 50 years and more than 40 million cooling units distributed worldwide, CSF is widely regarded as a luminary in the industry.

Additional Information

The Bulletproof Automotive website contains many thousands of products purchased in multiple different currencies. All of the prices are entered manually and accurately at the time of entry. Due to the consistently fluctuating international exchange rates, at times prices may not be able to be honored at their original intended rate. We apologize for any inconvenience this may cause, unfortunately our website is unable to compensate dynamically for what can at times be volatile changes in the cost of items due to currency values fluctuating, changes in prices from suppliers, changes in shipping and import duties, and other factors. Rest assured that any order you place on line will be at zero risk to you in this area. If in the event your order cannot be fulfilled at the original intended website price we will offer you a 100% refund, no questions asked. We will continue to do our best to maintain updated prices and we will always continue to offer our price match guarantees as well to ensure our prices are always the best for you. In short, prices may change without notice. It is always advised to give us a call prior to placing your order online to confirm availability and to confirm current pricing.

Shipping Policy

Items that are in stock in the US, either at Bulletproof’s warehouse or at a supplier’s warehouse, are generally delivered within 7-10 days. Special order items from overseas take considerably longer. As a courtesy Bulletproof offers delivery estimates to our customers which take into consideration manufacturer availability and shipping schedule. These estimates represent our best guess based on previous orders from the manufacturer and do not in any way imply a guaranteed delivery window. Many manufacturers work in a “just in time” inventory system and often take 2-20+ weeks to produce an item once an order is submitted. All deliverable items are then sent to our Japanese warehouse. Bulletproof ships a minimum of one full ocean freight container every month from Japan, oftentimes more than one a month. Ocean freight takes an average of 4 weeks. Typically it breaks down to one week in Japan for paperwork and customs, two weeks by boat and one week in US customs/clearance. Due to the wide number of variables between manufacturer and shipping schedules, delivery estimates are simply just that – estimates. We attempt to estimate conservatively and we usually deliver faster than our estimates suggest. It is not Bulletproof’s policy to guarantee delivery time of any special order item, this is impossible for us to do. By ordering you acknowledge that there is no required delivery ETA and an order may not be canceled or altered due to manufacturing or shipping delays, all ETA’s are provided as a best guess only. Please review the full Terms & Conditions here.

BP Pricing Difference

We do pricing a little differently on our JDM brands and we believe in making things simple and clear. No hidden fees or surcharges. Every price you see includes the shipping cost to our office in Los Angeles, California and all the associated taxes/duties/fees for bringing the products into the US. The only shipping you ever pay is from our facility in the US to your location. Be wary of resellers that don’t include the cost of international shipping in their pricing on JDM parts. While we believe we’ll always have the lowest all-in price on JDM products, we offer a price match guarantee for all authentic parts purchased from authorized dealers as well. For many international customers, it’s much more affordable to ship from the USA than from Japan directly, as the air freight and ocean freight costs are typically much less. However, for customers looking to ship directly from Japan outside of North America, or domestically in Japan, we can provide pricing specifically for that scenario. Please do not hesitate to contact us with any pricing questions or concerns. Please email us at sales@bulletproofautomotive.com with any inquiries.

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CSF High-Performance Auxiliary Radiators for Fxx BMW 340i, 430i, 440i, M140i, M2, and M240i [8355]

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CSF High-Performance Auxiliary Radiators for Fxx BMW 340i, 430i, 440i, M140i, M2, and M240i [8355]

Design & Engineering

OEM vs CSF

Construction

Features

Specifications

Applications

Notes

About CSF

Reviews