Small Block Chev 327-350-400 213cc CNC Ported Aluminium Cylinder Heads

Upgrade your small-block Chevy with a complete pair of CNC-ported Aeroflow aluminium cylinder heads for 327-350-400ci engines. Crafted from A356-T6 aluminium and featuring a 68cc chamber with 213cc intake runners, these heads are engineered to maximize flow from idle up to 7500 rpm while delivering reliable street and strip performance.

• Material: A356 aluminium (A356-T6) casting
• Chamber: 68cc
• Intake port volume: 213cc; intake port dimensions: 2.15" x 1.30"
• Exhaust port volume: 82cc; exhaust port dimensions: 1.45" H x 1.50" W
• Spark plug location: angled
• Intake valve diameter: 2.08"; Exhaust valve diameter: 1.60"
• Valve stem diameter: 8mm
• Valve spring pocket I.D.: 1.57"
• Valve guide material: manganese bronze; Guide O.D.:.502" (0.560" at base)
• Rocker stud thread size: 7/16" x 14
• Valve angle: 23°
• Deck thickness:.625"

The Aeroflow small-block Chevy heads feature a 5-angle competition valve job, diamond-honed bronze guides, hand bowl blending, and professional assembly to maximize flow and durability. They are designed to work with both mechanical and hydraulic roller camshafts and are suitable for street and strip applications.

• Spring and valve train readiness: larger than stock 1.57" diameter dual valve springs capable of up to 0.625" maximum lift
• Designed for 4.00" bore and larger
• Pair includes complete cylinder heads (Left and Right may be assumed in a pair)

Valve Train and Spring Details

• Installed height: 1.990"
• Installed pressure: 195 lbs
• Open pressure: 450 lbs @ 500"
• Maximum lift: 0.750" @ 1.240"
• Coil bind: 1.180"
• Spring outside diameter: 1.565"
• Spring inside diameter: 0.795"
• Spring free length: 1.470"
• Valve spring retainer outside diameter: 1.500"
• Valve spring inside diameter (retainer): 0.475"
• Valve spring retainer step 1: 1.120"
• Valve spring retainer step 2: 0.705"
• Valve spring locator outside diameter: 1.620"
• Valve spring locator inside diameter: 0.565"

Important notice: We recommend checking installed spring seat pressure and open pressure before installing your cylinder heads to ensure the spring pressure is correct for your application.

Applications and suitability: These complete CNC-ported heads are designed to provide excellent flow at a competitive price, ideal for 327-350-400 small-block Chevy builds that aim for strong street performance and competitive track results. They pair well with engines configured for idle to 7500 rpm and are compatible with mechanical and hydraulic roller camshafts.