ENGINE PRO RACING Chevrolet LS1 & 2 Cathedral intake ports, 15 degree

OE 4 Head Bolt Design

This head design is optimized for performance and reliability, featuring the following specifications:

Specifications:

• Material: Aluminium
• Combustion Chamber Volume: 63cc
• Intake Runner Volume: 235cc
• Intake Port Size: 3.23″ H x 1.10″ W
• Exhaust Runner Volume: 93.6cc
• Exhaust Port Size: 1.41″ H x 1.71″ W
• Intake Valve Size: 2.020″
• Exhaust Valve Size: 1.600″
• Valve Stem Diameter: 8.00mm
• Valve Length: Standard Length
• Valve Angle: 15 Degree
• Valve Guide Seal Diameter: 0.500″
• Valve Guide Material: Manganese Bronze
• Valve Spring Base Diameter: 1.358″
• Rocker Type: LS1 (Use OE Rocker Stand – Not Included)
• Notching of Stand: Maybe Required
• Deck Thickness: 0.625″

Flow Data @ 28″ (CFM):

Intake:

• @.300″: 205
• @.400″: 259
• @.500″: 294
• @.600″: 310
• @.700″: 300

Exhaust:

• @.300″: 139
• @.400″: 177
• @.500″: 210
• @.600″: 220
• @.700″: 226