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CID Heads - Competition Induction Designs

JK 400 CFM Big Block Chevy Cylinder Heads with as cast ports. (Price per pair BARE)

JK 400 CFM Big Block Chevy Cylinder Heads with as cast ports. (Price per pair BARE)

Regular price $2,950.00
Regular price $3,200.00 Sale price $2,950.00
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  • The CID JK400 Big Block Chevy Cylinder Heads flow an impressive 400CFM from as cast ports on a standard bore!

    This allows us to offer serious performance from an affordable cylinder head and intake package. These symmetrical port BB Chevy cylinder heads no longer have left and right unequal length runners. We straightened up the valve angles to move away from the factory bath tub chambers and to a smaller more efficient combustion chamber.

    In order to facilitate this, the valve angle has been stood up to 9.5 degrees. We added 0.750‚ thick decks. Valve train stability was also a priority so the rocker gear posts are robust enough for the most demanding applications. Everything you would come to expect from the experience gained manufacturing and developing the world renowned 3V Cleveland heads and intakes.

  • The JK400 cylinder head is a creation from Jon Kaase. It is designed to work on a 4.250 + bores and utilizes a 2.250" Intake valve, with a 1.750" Exhaust valve. The intake port flows 328CFM at .500" and near 410CFM at 1" lift.

  • The cylinder heads have their own matching intake manifold.

  • Their unique valve angles mean these heads require their own piston configuration. Pistons are available from CP, Ross and Diamond pistons. For those wishing to use another brand we can send CAD files or chamber molds to your preferred supplier.Chamber volume for this cylinder head is right around 88ccs.

Product Features

Manufactured in Melbourne Australia

  • Symmetrical intake port design ‚ no more left and right unequal intake ports. As Cast affordable intake and exhaust ports with CNC chambers.
  • Matching CID intake manifold available in both 9.8‚¬„¢ and 10.2‚ deck heights
  • STD Exhaust flange design raised .375‚ will accept factory headers.
  • 9.5 Degree Valve angle ‚ Factory bath tub chambers are replaced with a efficient modern chamber design
  • .750‚ thick deck face
  • Oversize rocker gear posts for maximum rigidity suit shaft mounted rocker gear system. Completely new rocker gear setup is far superior to Factory BB Chevy valve train.
  •  As Cast Intake Port JK400. Flow 410CFM @ 1" lift with a 2.250‚ valve. Flows 328CFM@.500‚ lift. 88cc CNC Chambers
  • Made to order and a "Final Sale"
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