PRC LS7x 285cc CNC Ported 400+CFM Heads
PRECISION RACE COMPONENTS
The Precision Race Components LS7 CNC 285cc Ported Cylinder Heads feature an all-new 6-bolt design developed for high-horsepower LS7-based combinations. Extensive CNC and dyno development delivers increased airflow while the thicker deck surface provides compatibility with both standard GM 4-bolt and aftermarket LSX/RHS 6-bolt-style engine blocks.
The larger 285cc intake runner is recommended for higher-horsepower applications with a minimum 4.125" bore. Flow testing on a SuperFlow 600 shows intake airflow reaching 407 CFM at .700" lift.
KEY FEATURES
- 285cc CNC-Ported LS7 Intake Runners
- PRC 6-Bolt LS7 Cylinder Head Design with Thicker Deck Surface
- 2.245" Titanium Intake Valves
- 1.610" Stainless Hollow-Stem Exhaust Valves
- TSP .660" Spring Kit with PAC Valve Springs
- Titanium Retainers
- CHE Bronze Valve Guides
- Compatible with Standard GM 4-Bolt and Aftermarket LSX/RHS 6-Bolt-Style Engine Blocks
- Cast, Machined, and Completely Assembled in the USA
CYLINDER HEAD SPECIFICATIONS
- Valve Angle: 12°
- Intake Runner Volume: 285cc
- Intake Valve: 2.245" Titanium
- Exhaust Valve: 1.610" Stainless Hollow Stem
- Chamber Size: 70cc
- Minimum Recommended Bore: 4.125"
FLOW DATA
Flow comparison data for the PRC 285cc LS7 cylinder heads and the tested GM LS7 cylinder heads:
| VALVE LIFT | LS7 INTAKE | LS7 EXHAUST | PRC 285CC LS7 INTAKE | PRC LS7 EXHAUST |
|---|---|---|---|---|
| .200" | 161 | 114 | 169 | 119 |
| .300" | 227 | 171 | 248 | 179 |
| .400" | 291 | 193 | 311 | 211 |
| .500" | 330 | 203 | 353 | 224 |
| .600" | 351 | 209 | 386 | 235 |
| .650" | 353 | 204 | 393 | 241 |
| .700" | 353 | 209 | 407 | 246 |
BLOCK COMPATIBILITY
- Standard GM 4-Bolt LS Engine Blocks
- Aftermarket LSX 6-Bolt-Style Engine Blocks
- Aftermarket RHS 6-Bolt-Style Engine Blocks
Note: The 285cc runner is recommended for higher-horsepower applications with a minimum bore size of 4.125". Valve spring lift ratings are based on the use of titanium intake valves.