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MAST LS3 Medium Bore Cylinder Heads

  • MAST LS3 255 Assembled Cylinder Heads
  • MAST LS3 255 Bare Cylinder Heads
  • MAST LS3 255 Deck View
  • MAST LS3 255 Combustion Chamber
  • MAST LS3 255 Combustion Chamber
  • Optional PAC 1521 Springs w/Titanium Retainers
Your Price:
$1,499.99 (You save $100.00)
50.00 LBS
Calculated at checkout

Product Description

MAST Motorsports - LS3 Medium Bore Cylinder Heads
The most powerful LS3 cylinder head available on the planet!

•  Designed for any new Gen IV short-block with 4.000" bore or larger
•  The six bolt design is compatible with GM LSX and World LSX blocks
•  Accepts Gen IV LS3 valvetrain and intake manifolds
•  2.165" intake valve - 1.600" exhaust valve
•  Fully CNC profiled combustion chamber
•  Deck thickness of .75"

Each Mast Black Label cylinder head assembly includes:

• A fully CNC machined Mast Black Label aluminum cylinder head
• PAC Racing dual valve springs
• Lightweight stainless steel intake & exhaust valves
• Lightweight chromemoly steel retainers
• Hardened and machined valve locks

NOTE:  Gaskets, valve covers, rocker arms and push rods not included -
Rocker stands available for stock rocker arm usage -
These heads can be customized with any valvetrain components you want. Titanium intake valves, PAC Racing valve springs, super alloy exhaust valves. You are only limited by your imagination. Contact us directly for more options and information.
MAST Flow Data w/4.070" Bore
Lift Intake Exhaust
0.100 77 56
0.200 148 118
0.300 237 165
0.400 295 208
0.500 328 227
0.600 351 235
0.700 370 241

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