BMW E23 745i Turbo Cylinder Head – M106 / M30 1288086

For sale is an original BMW turbo cylinder head for the BMW E23 745i, based on the legendary M30 engine architecture and specifically developed for the M106 turbo engine. These original turbo heads are very rare and increasingly difficult to find in usable condition.

This is a used cylinder head in good condition.

General Information

• Brand: BMW (OEM)
• Engine: M106 Turbo / M30-based
• BMW Model: E23 745i
• BMW Part Number / Casting: 1288086
• Condition: Used, good condition
  
• Material: Cast iron

Turbo-Specific Features (M106)

This cylinder head is based on a standard M30 head but includes important turbo-specific upgrades:

• Special exhaust manifold studs
• Nimonic exhaust valves and seats (high wear resistance for extreme turbo temperatures)
• Unique intake valves and seats
• Injector specification: 271 cc/min injectors on the intake manifold
• Smaller water channels compared to NA M30 heads for increased rigidity
• Rough (non-polished) intake ports from factory

These features provide significantly improved durability compared to a standard M30 cylinder head when used in turbo applications.

Shared Components with M30 Engines

The following parts are interchangeable with standard M30 engines:

• Camshaft: 264 degrees (M30B35 specification)
• Rocker arms and rocker shafts
• Valve guides and valve springs
• Camshaft gear, timing chain, and tensioner
• Head gasket: M30B35 type

Late M30B34 heads (including some E28 applications) also share the dual valve spring setup, improving valvetrain stability.

Technical Notes & Important Information

• Nimonic exhaust valves are designed for high-temperature turbo use
• A standard M30 head can be used as a substitute, but with reduced lifespan
• When resurfacing the head multiple times, a 2.0 mm thicker head gasket may be required
• Piston-to-valve clearance should always be verified (modeling clay method recommended)
• Always inspect for hairline cracks, commonly found between the exhaust valve seat and water jacket
• These turbo heads offer a durability advantage over stock M30 heads, especially on the exhaust side

Exhaust Manifold Compatibility

• Original M106 turbo exhaust manifold is a two-piece log-style design, unique to turbo engines
• Can be fitted to M30 heads with re-tapped threads (deeper bores required)
• Cracks on the turbo side of the manifold are common
• Wastegate may seize over time; soaking in thin oil usually resolves this
• Exhaust manifold should be re-torqued after break-in when installed on a new head or with new studs

Valve-to-Piston Clearance Reference (Measured)

Intake clearance (mm):

• Cyl 1: 2.6 (+0.3)
• Cyl 2: 2.5 (+0.2)
• Cyl 3: 2.6 (+0.3)
• Cyl 4: 3.3 (+1.0)
• Cyl 5: 2.5 (+0.2)
• Cyl 6: 2.6 (+0.3)

Exhaust clearance (mm):

• Cyl 1: 4.3 (+1.5)
• Cyl 2: 5.5 (+2.7)
• Cyl 3: 5.2 (+2.4)
• Cyl 4: 4.4 (+1.6)
• Cyl 5: 4.9 (+2.1)
• Cyl 6: 4.3 (+1.5)

Summary

• Rare original BMW M106 turbo cylinder head
• Correct casting 1288086
• Turbo-specific upgrades over standard M30 heads
• Used but in good condition
• Ideal for BMW E23 745i restoration or serious turbo M30 builds

Worldwide shipping possible.
Please feel free to contact us if you need additional photos, measurements, or technical clarification.