The BMW B4x Engine has the following critical specifications:
- Engine Block & Cylinder Head Metal Composition: Heat-Treated All Aluminium Made From AlSiMgCu0.5
- Crankshaft Material: Forged C38+N2 (B48E Crank is 1lbs lighter than the rest)
- Connecting Rod Material: "Drop-Forged" Material
- Piston Material: Cast Material (B48E has a higher silicon content)
- Bore Spacing: 91 mm
- Bore Size: 82 mm
- Displacement: 1.998 L
- Stroke: 94.6 mm
- Compression Ratio: Either 9.5:1 (B48E) or 10.2:1 (30i Model Cars) or 11.0:1 (20i & 30e Model Cars)
- Connecting Rod Centre to Centre: 148mm (B48E 146mm)
- Crank Throw: TBD
- Crankshaft Offset: 0 mm
- Wrist Pin Offset: TBD
- Main Caps: (B48E and B58 Share same Main Cap otherwise different)
- Cylinder Wall Plasma Arc Coating Thickness: 0.3 mm
- Cylinder Wall Thickness Between Cylinders: 9 mm
- Cylinder Wall Thickness on the Thrust & Non-Thrust Sides: 9 mm
- Intake Valve Diameter / Stem-diameter: 30.10 mm / 4.96 mm
- Exhaust Valve Diameter / Stem-diameter: 28.5 mm / 5.95 mm
- Maximum Valve-Lift, Intake/Exhaust Valve: 9.9 mm / 9.7 mm
- VANOS Adjustment Range, Intake: 70 °CA
- VANOS Adjustment Range, Exhaust: 60 °CA
- Intake Camshaft Spread: 122.5 - 52.5 °CA
- Exhaust Camshaft Spread: 120 - 60 °CA
- Opening Period, Intake Camshaft (Duration): TBD
- Opening Period, Exhaust Camshaft (Duration): TBD
- DME Used: MG1