Thitek GIIIH "Bear" | Custom Heads
GIIIH | Custom Heads For Extreme Builds Requiring Heads to Match.

GIIIH "Bear" | Custom Heads

If you can dream it, it probably can be done! From solid heads to a full on billet head, Thitek has the unique capability to radically customize heads for your build. Boost levels can be increased over what was reliable with a factory cylinder head casting, head gaskets stay put when using high boost pressures.

Need double spring heads milled out for the Jessel Rocker Arm Kit? Not a problem.

Contact one of our Certified Distributors for specific information on custom heads for your build.

Tech Specs

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


  • 11/32 Valves
  • 50 or 55 degree valve job
  • Additional Milling
  • Alternative valve lengths
  • Beehive or Dual Hyd roller valve Springs
  • Chamber coatings
  • Coated Titanium Valves
  • Copper Beryllium Valve Seats
  • Custom Port designs available
  • Hollow Stem Valves
  • Inconel Valves
  • Machining for Jesel Rocker arm kit
  • Optional 6 bolt head bolt pattern
  • Solid heads Available
  • Steel Valve guides
  • Steel Valve guides with bronze liner
  • Taper quench
  • Titanium locks
  • Up to 1.550” Dual Solid Roller Springs