B58 Heat Exchanger Upgrade for BMW & Supra Models

The 2nd-generation B58 cooling layout has one big weakness: the factory liquid-to-air charge-air cooler heat-soaks fast. Once the coolant saturates, intake temps climb, the ECU pulls power, and pushed hard enough the car drops into limp mode — a real limitation seen again and again at warm-weather track days, where modified B58s struggle to run more than a couple of laps without temps spiking.

The OEM unit is only 25mm thick with limited coolant capacity. RVNG's high-efficiency heat exchanger steps up to a massive 68mm dual-row core — over 2.5x the thickness, with dramatically more coolant volume and surface area. Optimized core geometry raises heat transfer, lowers pressure drop, and holds stable IATs under repeated pulls. It uses a housing and tank profile that fits cleanly in the OEM location, with billet transmission-cooler mounts and a full metal debris guard. Everything bolts in like stock — no cutting, no modification.

Highlights

• Massive 68mm dual-row core — over 2.5x thicker than the 25mm OEM unit
• Far more coolant volume and surface area for stable IATs
• Optimized geometry for higher heat transfer and lower pressure drop
• Billet transmission-cooler mounts and a full metal debris guard
• True drop-in fit in the OEM location — no cutting
• Works with B46, B48, and B58 engines

Fitment

• 2019-2022 BMW G20 / G21 330i and 330i xDrive (2.0L)
• 2021-2025 BMW G22 / G23 430i, G26 430i Gran Coupe and xDrive (2.0L)
• 2023-2025 BMW G42 M240i and M240i xDrive (3.0L B58)
• 2020-2025 BMW G20 / G21 M340i and M340i xDrive (3.0L B58)
• 2021-2025 BMW G22 / G23 M440i, G26 M440i Gran Coupe and xDrive (3.0L B58)
• 2019-2022 BMW G29 Z4 (2.0L and 3.0L)
• 2020-2025 Toyota GR Supra (3.0L and 2.0L), including A91-MT and 45th Anniversary editions

Ships from our Vancouver shop — KORE SPEED is proudly Canadian-owned, with no surprise cross-border duties for Canadian buyers. Questions on fitment? Email support@korespeed.com.