DESCRIPTION
Upgrade charge-air cooling with the do88 Intercooler. ICM-440-K fits BMW F/G-Series B58 Gen 1.
Enhance Your B58 Engine’s Performance with the do88 Charge Cooler Manifold
Background
The BMW B58 engine, introduced with the F-series platform, has proven to be an exceptionally capable and characterful powerplant, supporting impressive power levels with excellent drivability. However, when pushing performance beyond stock limits, certain factory components become limiting factors—both in terms of performance and long-term reliability.
The B58 is equipped with a water-to-air charge air cooling system paired with a front-mounted heat exchanger (water radiator). This heat exchanger cools the water circulating through the charge air cooler, which in turn reduces intake air temperatures before the air enters the engine.
On the B58 platform, the charge air cooler is integrated directly into the intake manifold. This creates a compact and complex assembly that places high demands on aftermarket design precision and manufacturing quality.
Challenges with the Factory Components
Owners of tuned B58 engines frequently encounter rapid heat soak in the charge air cooling system, particularly during track driving. Elevated intake air temperatures may cause the ECU to reduce engine output or, in extreme cases, activate limp-home mode. Even spirited street driving can lead to similar issues.
While the factory direct injection system offers clear advantages, it becomes a limiting factor for high-horsepower builds or ethanol-based fuel setups. To increase fueling capacity, many resort to installing port injection spacers between the intake manifold and cylinder head. Unfortunately, this positions the injectors at unfavorable angles, causing fuel to impact the intake runner walls and potentially leading to fuel puddling.
As with many factory components, the OE intake manifold becomes restrictive at elevated power levels. In addition to limiting airflow, its plastic construction poses a risk of cracking under high boost pressures.
The do88 Solution
High-Performance Bar & Plate Core
The do88 charge cooler manifold utilizes a motorsport-grade Bar & Plate air-to-water core featuring densely packed cooling fins for excellent heat transfer. The core measures 102 mm (4") in thickness and is carefully optimized for the B58 engine.
Both air-side and water-side fin characteristics have been thoroughly evaluated to achieve the ideal balance between cooling efficiency and airflow.
Innovatively Designed Cast End Tanks
Even distribution of charge air and cooling water across the core is achieved through precision-designed cast end tanks. Development included 3D scanning, multiple design iterations, CFD analysis, and 3D-printed prototypes before final validation.
Casting was chosen over CNC machining to allow more complex internal geometries that better support airflow and cooling performance. At do88, function and performance always take precedence over cosmetic appeal.
Engine Cover Compatibility
A key objective during development was retaining compatibility with the original engine cover. Many enthusiasts value maintaining a clean, factory-like engine bay, even in high-performance builds.
Considerable effort was invested to design a charge cooler manifold that delivers substantial performance gains while still allowing the use of the OE engine cover. This challenging requirement was successfully achieved.
With minor modifications, it is also possible to retain the engine cover when running auxiliary port injection. This requires removal of the sound-dampening material beneath the engine cover and hood, as well as installation of longer engine cover mounting pins (included in the kit). In this configuration, the engine cover sits very close to the hood; slight trimming or reshaping of the hood support structure may be required to increase clearance. This compatibility has been verified on BMW 340i F30/F31 models only.
Attention to detail is what sets the do88 solution apart. High-performance builds are often created by enthusiasts who value appearance just as much as outright performance—without compromise.
Intercooler Features:
Versatile Manifold Design – Fueling & Power Expansion Ready
The manifold outlet tank is pre-configured for auxiliary port fuel injection. A custom fuel rail with female AN-8 threads is available separately and bolts directly to the outlet tank. It is compatible with Injector Dynamics ID1050x-34-14 or Bosch EV14 Compact (K) fuel injectors.
If port injection is not used, injector blanking plugs are included. Each cylinder runner is also equipped with a dedicated 1/8” NPT port suitable for nitrous oxide or methanol injection—common power upgrades for the B58 platform. Sealing plugs are included.
Additional Measurement & Vacuum Ports
A 3-port sensor pad is integrated into the inlet tank casting, providing three additional 1/8” NPT ports. These can be used for pressure sensors, temperature sensors, or vacuum sources. Sealing plugs are supplied if unused.
Advanced Thermal Management
Included with the intake manifold is a specially engineered thermal barrier spacer designed to insulate the aluminum manifold from conductive heat transfer originating from the cylinder head. This reduces intake air temperatures, improves charge cooler efficiency, and minimizes heat soak.
Unlike the OE plastic intake manifold, the do88 unit is constructed from aluminum to withstand significantly higher boost pressures. The thermal spacer counters aluminum’s natural heat conductivity and seals using custom high-spec FKM silicone O-rings installed in precision-machined grooves. This provides a far more reliable seal compared to traditional gasket or sealant-based solutions.
Kit Contents:
- High-performance Bar & Plate air-to-water intercooler core, 102 mm (4") thick with 11 water cooling rows (OE has 6).
- Lower inlet air temperature under identical conditions: 26 °C vs OEM 40 °C (see diagrams under product images).
- Improved airflow and reduced backpressure: 873 CFM vs 615 CFM at 0.1 bar / 1.45 psi pressure drop – 42% increase.
- Peak power gain of 5 hp measured on a BMW 340i (2017) with bootmod3 Stage 2+.
- Maximum midrange power gain of 18 hp.
- Maximum torque gain of 28 Nm.
- Designed in SolidWorks using Computational Fluid Dynamics (CFD).
- Easy access to spin-off oil filter – no need to remove the manifold during oil changes.
- Integrated sensor pad with three 1/8” NPT ports (sealing plugs included).
- Optional auxiliary port injection fuel rail (sold separately).
- Injector blanking plugs included for each cylinder runner.
- Individual 1/8” NPT ports on each runner for nitrous or methanol injection.
- Plug-and-play installation requiring no vehicle modifications.
- All required brackets included for wiring and engine cover installation.
- Compatible with OE engine cover; compatible with modifications when running port injection (verified on BMW 340i F30/F31).
- Thermal barrier spacer included to reduce conductive heat transfer.
- Custom high-spec FKM silicone O-rings included for both spacer and manifold (12 pcs total).
OE Reference Numbers:
11618603913
Vehicle Fitment:
Model: BMW M140i / M140iX (F20 / F21)
Engine: B58 Gen 1
Model years: 09/2015–
Model: BMW M240i / M240iX (F22 / F23)
Engine: B58 Gen 1
Model years: 09/2015–
Model: BMW 340i / 340iX (F30 / F31 / F34)
Engine: B58 Gen 1
Model years: 10/2014–
Model: BMW 440i / 440iX (F32 / F33 / F36)
Engine: B58 Gen 1
Model years: 03/2015–
Model: BMW 540i / 540iX (G30 / G31)
Engine: B58 Gen 1
Model years: 10/2015–
Model: BMW 640i / 640iX (G32)
Engine: B58 Gen 1
Model years: 09/2016–
Model: BMW 740i / 740iX (G11 / G12)
Engine: B58 Gen 1
Model years: 10/2014–
Model: BMW X3 M40iX (G01)
Engine: B58 Gen 1
Model years: 10/2016–
Model: BMW X4 M40iX (G02)
Engine: B58 Gen 1
Model years: 03/2017–
TECHNICAL DETAILS
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