Advanced Engine Performance

More Holden VN style factory OEM Cast Iron CNC heads shipping, these Version 3/355 heads are sized for capacities around 355 Cube and have enough airflow and volume for 650+ HP on pump fuel 98 and are specifically designed to provide the widest torque and power curves available. Our higher versions provide even more power.

Our new for 2025 Version 3/355 early "B" cast style factory Cast Iron heads shipping. After probably 6 months of on and off dyno testing using our 355 Cube dyno development engine we pushed the power to 585 HP, and these are probably good enough for 600+ HP with an aggressive camshaft. These made an astonishing 479 FT LBS of torque and 540 HP with an untouched under bonnet Edelbrock Performer dual plane intake at 6800 RPM, our best CNC single plane intake made a massive 496 FT LS of torque and 585 HP at 6900 RPM, all on pump fuel 98, every other manifold we tested made less torque or power.

More Holden "B" cast style OEM Cast Iron CNC heads shipping. These Version 1/355 HC heads are designed for capacities around 355 Cube or higher RPM 308 Cube under bonnet engines and to provide the widest possible torque curve with power in the 400-450 HP range with hydraulic camshafts on pump fuel 98.

More Holden VN style factory Cast Iron CNC heads shipping this week, these Version 3/383 heads are sized for capacities around 383 Cube and have enough airflow and volume for 625+ HP on pump fuel 98 and are specifically designed to provide the widest possible torque and power curves at lower RPM, for lower convertor stall speeds and more driveability. Combine it with one of our custom Street SR cams and make even more torque and power at the same RPM. Our higher versions provide even more power.