OVERVIEW
The CSF #8321 High-Performance Auxiliary Radiator is a substantially stronger part than the OEM auxiliary radiators it replaces. TIG-welded aluminum tanks take the place of the factory plastic tanks, giving greater strength and holding more fluid, and the core steps up from the OEM's single 34mm row to a 2-row 42mm design featuring CSF's exclusive B-tube technology. Ultra-efficient 5mm tall multi-louvered fins increase surface area contact for more effective heat rejection and improved airflow.
Construction is 100% aluminum throughout, which guarantees both performance and long-term durability, and the mounting pins and brackets are far tougher and longer-lasting than the OEM plastic pod mounting system. The unit is multi-fit, working on both the left and right sides of the car, and includes a detachable bolt-on rock guard to protect the core. Every unit is individually leak and pressure tested. The satin black finish adds protection and gives a clean OEM+ appearance behind the grilles of your G8X.
SPECS
- 2-row, 42mm high-performance core featuring CSF's exclusive B-tube technology (OEM: 1-row, 34mm)
- Ultra-efficient 5mm tall multi-louvered fins for maximum surface area contact
- Increased tank volume and core size over OEM
- 100% all-aluminum TIG-welded construction (OEM: plastic tanks, crimp-on gasket)
- OEM-style "quick connect" inlet and outlet
- Multi-fit — fits both left and right side
- Includes detachable bolt-on rock guard
- Individually leak and pressure tested
- True "drop-in fit" — requires no modifications to install
- Satin black finish for an OEM+ look
- Suitable for professional racing, street performance or OEM replacement
- OEM cross-reference: BMW 17 11 8 095 285
- 2-year limited warranty
PARTS INCLUDED
- One CSF #8321 high-performance auxiliary radiator
- Detachable bolt-on rock guard
- Mounting pins and brackets
TECH RESOURCES
Additional Parts Required
- A second CSF #8321. The radiator is sold individually and every application requires two — order quantity 2 for a complete installation.
- Coolant for refilling and bleeding the cooling system after installation (installer supplied).
- No other additional hardware is required. CSF specifies a true drop-in fit using the OEM quick-connect lines and mounting locations.
Installation
- CSF does not publish a downloadable installation PDF for this part. Printed installation instructions are supplied in the box.
- Installation requires no modification to the vehicle; the radiator is multi-fit and mounts on either side using the supplied pins and brackets.
Notes
- Sold individually — all applications require two auxiliary radiators.
- Fits both 6-speed manual and ZF8 automatic cars.
- The G81 M3 Touring is not sold in North America. Confirm fitment for your specific chassis with Speed Logic before ordering.
PART NUMBER
- 8321 — CSF BMW G8X M3/M4/M2 High-Performance Auxiliary Radiator (satin black)
VEHICLE APPLICATIONS
| Make | Model | Chassis | Engine | Years |
|---|---|---|---|---|
| BMW | M2 | G87 | S58 3.0L Twin-Turbo I6 | 2023+ |
| BMW | M2 CS | G87 | S58 3.0L Twin-Turbo I6 | 2026+ |
| BMW | M3 | G80 | S58 3.0L Twin-Turbo I6 | 2021+ |
| BMW | M3 Competition | G80 | S58 3.0L Twin-Turbo I6 | 2021+ |
| BMW | M3 Competition xDrive | G80 | S58 3.0L Twin-Turbo I6 | 2022+ |
| BMW | M3 CS | G80 | S58 3.0L Twin-Turbo I6 | 2024+ |
| BMW | M3 Touring | G81 | S58 3.0L Twin-Turbo I6 | 2023+ |
| BMW | M4 | G82 | S58 3.0L Twin-Turbo I6 | 2021+ |
| BMW | M4 Competition | G82 | S58 3.0L Twin-Turbo I6 | 2021+ |
| BMW | M4 Competition xDrive | G82 | S58 3.0L Twin-Turbo I6 | 2022+ |
| BMW | M4 CS | G82 | S58 3.0L Twin-Turbo I6 | 2025+ |
| BMW | M4 CSL | G82 | S58 3.0L Twin-Turbo I6 | 2023 |
| BMW | M4 Convertible | G83 | S58 3.0L Twin-Turbo I6 | 2022+ |


