As with most turbocharged vehicles, cooling is absolutely essential for the BMW S55 engine to achieve high levels of performance consistently. When engines get hot, their performance and efficiency drops (also known as heat soak). The OEM BMW cooling system for S55 powered vehicles (BMW F80 M3, F82 M4 and F87 M2 Competition) does a pretty good job at OEM power output. However, there are some reliability concerns and tuning limitations to be aware of. That's where CSF Radiators come in.
As we are looking to tune our BMW F87 M2 Competition, upgrading the cooling system was essential for reliability and efficiency.
Why upgrade your BMW S55 cooling system?
1. Reliability
Whilst the OEM radiators and cooling system can provide adequate cooling, the components are built to a cost. Unfortunately, we've seen and experienced many failures in the S55's cooling system due to perished OEM components. BMW don't use the highest quality materials which limits durability.
As most S55-powered BMWs are getting on in age, the OEM radiators on many examples have become very tired or damaged. When we removed the factory heat exchanger from our BMW F87 M2 Competition, for example, we noticed lots of damaged cells and a lot of wear and tear.
The OEM charge cooler failed on our F80 M3 track car which ended up requiring an entire replacement S55 engine. We know from experience how fragile the OEM cooling system becomes over time.
2. Tuning Potential
When tuning a turbocharged engine like the S55, heat becomes a huge limiting factor that prevents you from pushing higher horsepower. Not only does a more effective cooling system allow you to achieve a higher peak power, it allows you to maintain peak power for longer. If you took your car on a track day, for example, temperatures get very high and your vehicle may suffer from excessive heat soak. Increased cooling capacity will help you counter this and maintain your engine's performance.
Why choose CSF Radiators?
CSF has been around for a long time and have an outstanding reputation for quality and durability. The price-point is very fair considering the value they provide through their design, engineering and customer aftercare.
We were really happy with how the CSF upgrades performed on our F80 M3 track car so we decided to opt for the exact same setup on Dylan’s M2 Competition with the addition of the all-new auxiliary radiators. The car is about to be Stage 2 tuned (possibly even further) so a full overhaul of the cooling system was needed.
We know that the factory cooling setup is pretty good out of the box but the CSF upgrades have larger cores, better capacity and have a much better build-quality. As the F Series cars are starting to get on in age, the factory items get damaged or just become a bit tired so instead of replacing them with OEM items, upgrading to CSF is definitely the way to go.
A major selling point that drew us to CSF was the integrated rock guards. The OEM radiators are left completely exposed leaving your car one rock away from some serious problems - not something you want to happen on track when temps are high!
Installing CSF Radiators for the BMW S55 Engine
As for installation, the process was very straightforward. It's just like installing OEM parts using the factory mounting points and connections. As with any repairs or upgrades to a vehicle's cooling system, it can get quite messy with draining fluids. Best practise is to perform a full flush of the cooling system with OEM BMW coolant and, if installing the S55 engine oil cooler, ensure you measure and top up the oil once fitted.
Accessing each component is relatively easy once the front bumper is removed. It's far easier when working on a ramp. We wouldn't advise installing these parts on jack stands but if you can make it work, go for it!
Final Results: Are CSF Radiators worth it?
With CSF, you won't see any instant performance increase in terms of power. The true benefits will be uncovered during tuning, driving hard for long periods of time and through long-term reliability.
We’ll be sharing the full tuning process in the near future so definitely stay tuned for that.
Our head of content, Dylan, is known for not being the most gentle with his car. He arrives to work everyday doing a burnout up the road so the car does get put through its paces. It goes without saying that there have been absolutely no issues with the parts so far + even if there had been, each component is covered under warranty which just gives us peace of mind.
We’ve left some of the key features & specs of each component below in case you were curious. You can check out the full package here: https://r44performance.com/collections/csf-radiators-bmw-s55-engine
CSF Radiators S55 Specifications
Top Mount Charge Cooler
- **60% Increase in Core Size Compared to the OEM Cooler
- Left/Right, Cross-Flow, Dual-Pass Core Configuration with 2-Stage Water Cooling for Maximum Efficiency and Intake Temperature Reduction (vs. OEM Single-Pass Vertical-Flow Design)
- Designed with 3D Scanning/Rapid Prototype Technology to Ensure Precise Fitment and Maximum Surface Area Utilization
- “Drop-in Fit” Design for an Easy & Quick Plug-and-Play Installation, Complete with OEM-Style “Quick-Connect” Water Connections and Sensor Ports
Heat Exchanger
- 2-row 42mm Core (Dual Core) Featuring CSF’s Exclusive B-tube Technology
- Core Features an Ultra-Efficient Fin with 6.5mm Fin Height and Multi-Louvered Design for Maximum Surface Area Contact
- Dual-Pass Flow Structure Allows the Coolant to Flow Across the Core of the Radiator Two Times Before Exiting the Radiator for the Lowest Outlet Temperature Possible (OEM Style Design)
- CNC Machined, OEM-Style “Quick-Connect” Inlet/Outlet Connections
- CNC Machined, OEM-Style Mounting Brackets & Fittings for Superb Fit and Durability
- Includes Removable Aluminum Rock Guard
- All-Aluminum Race Style Drain Plug
Auxiliary Radiators
- 2-Row 42mm High-Performance Core Featuring CSF’s B-Tube Technology
- Ultra Efficient 6.5mm Tall Fins with a Multi-Louvered Design for Maximum Surface Area Contact
- Tank Volume increased by 10% and Core Size Increased by 6.4%
- 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
Engine Oil Cooler
- 5.4mm Tall Multi-Louvered Fin vs. OEM 7mm
- Made with CSF’s AC Condenser Technology Using a 1-Row Super-High Pressure 32mm 10-Channel Microtube for Optimal Oil Flow and Maximum Surface Area Contact
- Utilizes OEM Top/Bottom Rubber Seals for Optimal Airflow
- OEM Style Inlet/Outlet Connections
- Drop-in Fit Requires No Modifications to Install
