Thitek GIIIH "Bear" Cylinder Heads
Thitek GIIIH "Bear" The Only 100% Aftermarket Gen III Hemi Heads

GIIIH "Bear" - Overview

The Thitek GIIIH "Bear" is the first aftermarket available cylinder head for the Late Model Hemi platform. A true bolt on cylinder head design that replaces the factory cylinder head with no other modifications needed.

The ultimate in performance upgrade for your G III / IV late model engine. Airflow has been increased from over 75 cfm on the 2.125" 200 cc head to over a whooping 100 cfm on the 2.165" 205cc head over factory as cast cylinder heads. A high flow exhaust port design increases airflow over 50 cfm over the factory designs.

Increased performance and reliability are two of the main benefits of using the "Bear". Gains in performance over factory ported cylinder heads have been seen over 50+ rear wheel and gains at the track of over a full second in the quarter mile. Boost levels can be increased over what was reliable with a factory cylinder head casting, head gaskets stay put when using high boost pressures.

Tech Specs

  • A356 T6 Aluminum
  • Completely New Casting
  • Form treads
  • Increased Deck thickness
  • Increased port wall thickness
  • Interchangeable (Left – Right)
  • Reinforced Rocker Arm Stands


  • Beehive or Dual Hyd roller valve Springs
  • Coated Titanium Valves
  • Copper Beryllium Valve Seats
  • Custom Port designs available
  • Hollow Stem Valves
  • Inconel Valves
  • Optional 6 bolt head bolt pattern
  • Solid heads Available
  • Steel Valve guides
  • Up to 1.550” Dual Solid Roller Springs

GIIIH "Bear" Standard Versions

Cast Porters

Thitek GIIIH "Bear" | Cast Porters
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CNC Ported

Thitek GIIIH "Bear" - Bare CNC Ported
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CNC Ported | w/ Beehive

Thitek GIIIH "Bear" - Assembled CNC Complete Beehive
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CNC Ported | w/ Dual Springs

Thitek GIIIH "Bear" - Assembled CNC Complete Dual Spring
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Custom Heads

Thitek GIIIH "Bear" | Custom Heads
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