Hitman X 12° Spread Port CNC Machined Big Block Chevy Cylinder Heads
P/N: 184-X-C49-03
- Accepts up to 1.655 O.D. Springs
- Bronze valve guides reduce stem wear
- 530cc Intake Runners
- Pro-Stock Port Design promotes high intake port velocity
- 60cc CNC Machined Nitrous Friendly Chambers
- 2.500" Intake / 1.850 Exhaust Valves
- Made in the U.S.A.
The Hitman X is an awesome choice when building an engine to use power adders such as nitrous and superchargers. You can now choose the perfect runner and chamber for your bigger applications. The CNC 490cc intake port is available with a 62cc, 72cc, or 74cc chamber.
Details
Series P/N: 184X BBC Hitman Head Specifications
| Material: | Aerospace Specification, A356 Aluminum Alloy (Primary Virgin Ingot) |
| Valve Angle: | 12 Degree valve angle |
| Intake Ports: | Spreadport Location Oval-Shaped, Fully CNC Machined 530cc |
| Exhaust Ports: | Round, Raised Port, Fully CNC Machined |
| Exhaust Valve Diameter: | 1.850" - 6.800 long (2.200 Install), 11/32 Stem |
| Intake Valve Diameter: | 2.500" - 6.800 long (2.200 Install), 11/32 Stem |
| Deck Thickness: | 1/2" deck for Nitrous and Blown applications |
| Valve Guides: | Manganese Bronze to assist in extending valve life |
| Bore Spacing: | Standard BBC 4.840" |
| Spring Pocket: | Maximum of 1.655 (no deeper) |
| Valve Seats: | 55°Copper Alloy |
| Combustion Chamber: | Heart-Shaped, CNC 60cc |
| Milling: | .005 per cc flat milling, .007 per cc angle milling |
| Spark Plugs: | Revised location to improve flame travel. Machined for a gasketed 3/4" reach plug NGK R5671A-7 or colder |
| Valve Covers: | Uses Pro-Filer PN 190 |
| Valve Diameter: | 2.450" intake / 1.885 Exhaust |
| Valve Train: | Shaft rockers (T & D, Jesel) |
| Engine Size: | 565+ cid / 9000 RPM |
| Application: | High Performance (i.e. street / strip / marine) |
| Intake Manifold: | Profiler Hitman Series 208 Single Plane or Hitman Series 187 Tunnel Ram |
Air Flow Detail #184X BBC Hitman CNC Head - 490cc Runner
Pro Filer Hitman X CNC Big Block Chevy Heads with 490cc Intake Runner, 2.450" Intake Valve and 1.850" exhaust valve. Flow data based on Cylinder #1 intake and exhaust port. Flow measured at 28" of depression.
Air Flow Detail #184X - 490cc Runner
| Lift | Intake CFM | Exh CFM | % Exh/Int |
|---|---|---|---|
| 0.200 | 150 | 105 | 70% |
| 0.300 | 234 | 154 | 66% |
| 0.400 | 311 | 197 | 63% |
| 0.500 | 382 | 240 | 63% |
| 0.600 | 492 | 286 | 58% |
| 0.700 | 511 | 313 | 61% |
| 0.800 | 522 | 343 | 66% |
| 0.900 | 540 | 355 | 66% |
Air Flow Chart #184X - 490cc Runner
Air Flow Detail #184X BBC Hitman CNC Head - 515cc Runner
Pro Filer Hitman X CNC Big Block Chevy Heads with 515cc Intake Runner, 2.450" Intake Valve and 1.850" exhaust valve. Flow data based on Cylinder #1 intake and exhaust port. Flow measured at 28" of depression.
Air Flow Detail #184X 515cc Runner
| Lift | Intake CFM | Exh CFM | % Exh/Int |
|---|---|---|---|
| 0.200 | 155 | 130 | 84% |
| 0.300 | 234 | 183 | 78% |
| 0.400 | 311 | 238 | 77% |
| 0.500 | 390 | 293 | 75% |
| 0.600 | 450 | 325 | 72% |
| 0.700 | 511 | 348 | 68% |
| 0.800 | 541 | 368 | 68% |
| 0.900 | 555 | 380 | 68% |
| 1.000 | 561 | 388 | 69% |
Air Flow Chart #184X - 515cc Runner
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