Hitman 12 Degree Big Block Chevy Cylinder Heads

Race Winning Performance out of the box...
  • Accepts up to 1.650 O.D. Springs
  • Bronze valve guides reduce stem wear
  • Pro-Stock Port Design promotes high intake port velocity
  • 60cc Combustion Chambers allow lighter pistons, more compression and better combustion.
  • Made in the U.S.A.
  • BBC 184 Series Hitman Racing Heads
  • BBC 184 Series Hitman Racing Heads
184 Series 12 Degree Hitman BBC Heads

The Hitman BBC 12º Spreadport takes the guess work out of trying to find the right cylinder head for the most power. Based on Pro-Stock technology, the Hitman offers an out-of-the-box port design that allows any racer or engine builder to have an efficient, high velocity airflow cylinder head within their grasp. Providing you with power over your opponents.

The Hitman Series cylinder heads feature a heart shaped combustion chamber, an oval-shaped port design that is available as a proprietary PRECISION As-Cast or Fully CNC version, and the unmistakable Pro-Filer casting quality.

Pro-Filer Hitman 12°
BBC Spread Port
Racing Cylinder Heads

Your choice of 415cc or 470cc Intake ports with 60cc N/A, 72cc or 74cc Nitrous Friendly Chambers.

  • Copper Alloy Seats Included
  • Your Choice of 5/16 or 11/32 Guide Dia.
  • Valve Job (Int/Exh): 2.400/1.880 Included

Series 184
Base Price (each):

Intake Port Size
Chamber Size
Valve Guide Size
Spring & Retainer Options
Casting Style - Coolant Passages

Air Flow Chart

Note: Flow rates may vary for any number of circumstances due to valve job, valves, the flow bench used, test parameters, etc.

Hitman 12 Degree BBC Racing Cylinder Heads

Material: Aerospace Specification, A356 Aluminum Alloy (Primary Virgin Ingot)
Valve Angle: 12 Degree
Intake Port Volume and Shape: Spreadport Location Oval-Shaped, PRECISION As-Cast 415cc & 470cc
Exhaust Valve: 1.850-1.880" - 6.800 long (2.200 Install)
Intake Valve: 2.400"-2.450" - 6.800 long (2.200 Install)
Valve Spring Pocket: Maximum of 1.655 (no deeper) Combustion Chamber: Heart-Shaped, As-Cast/CNC - 60cc (CNC 72cc & 74cc Power Adder)
Milling: .005 per cc flat milling, .007 per cc angle milling
Deck Thickness: 1/2" deck for Nitrous and Blown applications
Spark Plugs: Revised Location to improve flame travel. Uses Gasketed 3/4" Reach Plugs such as NGK R5671-7 Series
Valve Train: - Uses T&D or Jessel Shaft Mounted Rocker Systems
Bore Spacing: - 4.840 (Standard Big Block)
Valve Guides: Manganese Bronze to assist in extending valve life
Valve Seats: Copper Alloy
Intake Port Design: Pro-Stock Modified Oval Port
Valve Covers - Pro-Filer PN 190
Rockers - Shaft rockers (T & D, Jesel)
Engine Size Recommendation:565+ cid / 9000 RPM
Application: High Performance (i.e. Street/Strip/Marine)

Parts and Accessories

Intake Manifolds: Hitman Single Plane or Hitman Tunnel Ram

Pro-Filer Performance Products
PO Box 217
New Carlisle, OH 45344
United States of America
Phone: 937-846-1333
Email: info@profilerperformance.com
Proudly Made in America