do88 S58 Auxiliary Radiator BMW G8X M2 M3 M4

By DO88
£471.00

Strengthen Your Cooling System with the do88 Auxiliary Radiator 

Tuned G8X M-cars generate serious heat — especially during track use. The factory auxiliary radiators with their slim cores and plastic end tanks simply can’t keep up. Enter do88’s all-aluminium performance upgrade: a direct-fit solution designed to boost cooling capacity, eliminate heat soak, and withstand the demands of high-performance driving.

Why Upgrade?

A Common Bottleneck in S58 Cooling Systems

The S58 engine is equipped with a three-radiator setup — one main central radiator and two smaller auxiliary radiators in the corners. These auxiliary radiators are critical for helping maintain coolant temps under sustained load. Unfortunately, the factory units are built with narrow cores and plastic end tanks, which become a weak point on tuned or hard-driven vehicles.

Bigger, Stronger, Cooler

do88’s auxiliary radiators are not just stronger — they’re larger and more efficient. With a 43% increase in core volume and a 13% increase in frontal cooling area, these TIG-welded aluminium upgrades help prevent heat soak and maintain stable coolant temps under pressure.

Key Features

  • 43% larger core volume vs. OEM

  • Dual-row 48mm thick core

  • 13% larger active cooling area

  • All-aluminium construction with TIG-welded end tanks

  • OE-style quick connect fittings for easy installation

  • CNC-machined mounting points

  • Compatible with factory rock guards

  • Direct-fit for both left and right sides

  • Sold individually (one per side)

Compatibility

  • BMW G87 M2 (2023–202X)

  • BMW G80 M3 / M3 Competition / M3 CS (2020–202X)

  • BMW G82 / G83 M4 / M4 Competition / M4 CSL (2020–202X)

  • For S58 engine cars only

Note: Sold individually – two required per car.

Supporting Upgrades Recommended

  • do88 Front Intercooler Radiator

  • do88 Inlet Manifold & Integrated Intercooler

  • do88 Charge Pipes

  • Upgraded coolant hoses

  • Motorsport-grade coolant fluid

Why Choose do88?

Swedish-engineered and CFD-tested, do88 products are built with serious motorsport in mind. Whether you're daily driving or chasing lap times, these radiators offer proven reliability and performance where it counts.

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