Dart Machinery, LTD. stands behind each product we manufacture 100%. Each component undergoes a detailed manufacturing process that involves the hundreds of calculated and precision steps to ensure the finest quality possible.

Warning This product contains chemicals known to the State of California to cause cancer and reproductive harm. www.P65Warnings.ca.gov
PRO1 24 355cc CNC

PRO1 24° 355cc CNC

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Maximum performance, bracket racing, heads up and super classes. Over 7,500 RPM, 540+ cubic inches, a great head for maximum effort comp or bracket cars.

The PRO1 24° 355cc CNC heads are for uncompromising performance and racing applications which favor high RPM power over low end flexibility. Best for big cubic inch, high RPM use.

Every intake port, exhaust runner, valve bowl, and every combustion chamber is 100% CNC machined on special dedicated PRO1 castings. Our 5-axis, computer controlled machining centers produce compound curves and complex shapes that no human could duplicate with a hand grinder.

Assemblies include Stainless Steel valves, premium springs, locks, retainers, guide plates and seals.

Heads are sold individually.


Material: RMR Cast Aluminum Alloy

Valve Angle: 24° 

Intake Port Volume: 355cc CNC

Intake Valve: 2.300”

Exhaust Valve: 1.880”

Chamber Volume: 121cc

Intake Port Shape: Rectangle

Exhaust Port Location: .300” raised

Dart Marine PRO1 cylinder heads

Features an exclusive chromate surface finish to inhibit corrosion and extend the life of the head.

Fitted with Inconel exhaust valves to withstand the extended running time and temperatures typical of marine usage.

PRO1 24° 355cc CNC – Aluminum

19574030 – Bare Head

19574136 – 1.625” Dual Springs for Solid Roller .850”

19574139 – 1.650” Triple Springs for Solid Roller Cam .900”

PRO1 24° 355cc CNC – Aluminum (Marine Heads)

19574030M – Bare Head

19574136M – 1.625” Dual Springs for Solid Roller .850”

PRO1 CNC 335 & 355 Tech Sheet – H41