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CID Heads - Competition Induction Designs

CID DM 500 CNC Ported Symmetrical Port Big Block Chevy heads (Price per pair BARE)

CID DM 500 CNC Ported Symmetrical Port Big Block Chevy heads (Price per pair BARE)

Regular price $3,950.00
Regular price $4,200.00 Sale price $3,950.00
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The CID DM 500 CFM Big Block Chevy head was a first for Australian Cylinder Head manufacturing at the time of their conception. Now these heads are made in the USA. At CID we wanted to address the issues associated with the factory BBC heads. First of all we wanted to make our head a symmetrical port head. No more 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 CNC DM500 cylinder head is a creation of Darin Morgan from Reher Morrison. It is designed to work on a 4.6" + bore and utilizes a 2.4" Intake valve, with a 1.850" Exhaust valve. The intake port flows 430CFM at .600" and near 500CFM at 1" lift.

The cylinder heads have their own matching intake manifold, also courtesy of Darin Morgan pictured below.

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 60ccs.

Product Features

  • Manufactured in USA
  • Symmetrical intake port design – no more left and right unequal intake ports. CNC 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 with Jesel rocker gear available for purchase. Completely new rocker gear setup is far superior to Factory BB Chevy valve train.
  •  CNC Intake Port DM500. Will flow 500C+FM with 2.450” valve. Flows 440CFM@.600” lift.
  • 60cc Chambers
  • Made to order and a "Final Sale"
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