The ultimate upgrade for your LS3 or LSA engine is here. Mast Motorsports LS3/LSA 255 Black Label heads are at the forefront of power and performance. Designed from a clean sheet this head supports 600+ horsepower on stock bottom end LS3 engines with supporting modifications. If you are looking to upgrade your LS3 or LSA with the best aftermarket LS head on the market, look no further.
- Designed for LS short-blocks with 4.000" bore or larger
- The 6-Bolt design is compatible with GM LSX and World LSX blocks
- Accepts Gen IV LS3 valvetrain and intake manifolds.
- Uses a 2.165" intake valve and 1.600" exhaust valve
- 11 Degree Valve angle
- Has a 255cc intake port
- Has a 69cc combustion chamber standard
- Has a deck thickness of .750"
- Cast & Machined in the USA!
| Flow Data w/4.000" Bore Plate | ||
| Lift | Intake | Exhaust |
| 0.100 | 74 | 61 |
| 0.200 | 146 | 119 |
| 0.300 | 222 | 188 |
| 0.400 | 282 | 219 |
| 0.500 | 330 | 236 |
| 0.600 | 360 | 251 |
| 0.700 | 372 | 260 |
