The G-chassis cars run a smarter cooling layout than the generations before them. Engine coolant now passes through the front heat exchanger as well as the intercooler circuit, so it helps cool the whole engine. It is still a factory part built to a budget. Push your M340i, 430i, Z4 or GR Supra hard, or add power, and it gets overwhelmed. Charge temperatures climb and the power fades.
The Dinan High Performance Heat Exchanger for the BMW G20, G22 and G42, the G29 Z4 and the Toyota GR Supra fixes that with a far bigger core. Dinan's unit is 45mm thick against 26.75mm for the factory part, with 68% more heat transfer surface area. In Dinan's testing it lowered charge air temperatures by an average of 8.7°C, with a maximum reduction of nearly 12°C over 30 back-to-back wide open throttle pulls.
How the Dinan Heat Exchanger Keeps Your B58 or B48 Cool
The thicker core and full-size end tanks raise thermal mass, which is how much heat the cooler can absorb, store and release before it saturates. That buys you more hard pulls, more laps and more consistent power before the ECU starts protecting the engine. Because the factory system routes engine coolant through this cooler too, the upgrade helps overall engine cooling, not just charge air.
It is a bar and plate aluminum core, 100% TIG welded and pressure tested. Bar and plate is the durable choice for a part that lives right behind the front bumper and sees every pebble on the highway.
Dinan Heat Exchanger Fitment and Legal Status
One part covers the four and six cylinder G-chassis BMWs listed below, rear-wheel drive and xDrive, and the GR Supra in both 2.0 and 3.0 form. It is a direct fit replacement for the factory unit. Before you order, know this: it is not legal for sale or use in the State of California. It is sold under the EPA Tampering Policy for other states, and a CARB Executive Order is pending. Dinan part number D780-0003. Sold by AutoTecknic, an authorized Dinan dealer.
What's Included
- Dinan High Performance Heat Exchanger
Key Features
- 45mm core vs 26.75mm factory core
- 68% more heat transfer surface area than stock
- Dinan-tested average 8.7°C lower charge air temperature
- Maximum reduction of nearly 12°C over 30 successive WOT pulls
- Full-size end tanks add thermal mass
- Bar and plate aluminum core, 100% TIG welded and pressure tested
- Direct fit replacement for B46, B48 and B58 G-chassis cars
Vehicle Fitment
Fits the following B46, B48 and B58-powered models:
- BMW 3 Series / G20 Sedan (2019-2026): 330i, 330i xDrive, M340i, M340i xDrive
- BMW 4 Series / G22 Coupe (2021-2026): 430i, 430i xDrive, M440i, M440i xDrive
- BMW 4 Series / G23 Convertible (2021-2026): 430i, 430i xDrive, M440i, M440i xDrive
- BMW 4 Series / G26 Gran Coupe (2022-2026): 430i Gran Coupe, M440i xDrive Gran Coupe
- BMW 2 Series / G42 Coupe (2022-2026): 230i, 230i xDrive, M240i, M240i xDrive
- BMW Z4 / G29 Roadster (2019-2026): sDrive30i, M40i
- Toyota GR Supra / A90 and A91 (2020-2026): 2.0 and 3.0
Not for G80 M3, G82 M4, G87 M2 or X models.
Installation Notes
Dinan rates this at about 3.7 hours of labor. The front bumper comes off, and because engine coolant runs through this cooler, the cooling system must be drained, refilled and bled correctly afterward. A careful DIYer can do it. A shop familiar with G-chassis cooling systems will get it done faster.
- Raise and support the car safely and let the engine cool fully.
- Remove the front bumper cover and drain the coolant from the heat exchanger circuit.
- Disconnect the hoses and remove the factory heat exchanger.
- Install the Dinan heat exchanger in the factory location and reconnect the hoses.
- Refill and bleed the cooling system as described in the Dinan instructions, then check for leaks before reinstalling the bumper.
