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Yella Terra Holden 6 Blue/Black 12-Port Alloy Cylinder Head — 74cc Bare — ACH 33C74
$2,450.00
ACH 33C74 is Yella Terra’s semi-finished 74 cc bare alloy cylinder head for Holden Blue/Black 12-port inline-six builds. The large chamber and additional deck material give the engine builder flexibility when setting compression and completing the head for a specific combination.
Bare-head specification
- 74 cc chamber in supplied form; Yella Terra notes the casting can be faced toward approximately 56 cc.
- Approximately 0.080 inch additional deck material for machining flexibility.
- Heat-treated 356-T6 aluminium construction.
- Valve seats are supplied rough cut and require final engine-builder machining.
- Yella Terra quotes approximately 240 hp potential in suitable out-of-box combinations and more than 300 hp with extensive CNC port development.
Bare / semi-finished component: Final seat work, guides, clearances, chamber volume, surface finish and valvetrain setup must be completed and verified by the engine builder.
Supplier
Yella Terra
Product System
- Engine Parts
Supplier Part Number
ACH 33C74
Built by Boost & Tune Support
BBT can assist with fitment review, installation, supporting modifications, configuration and calibration requirements where applicable.