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Vehicle Info NeededPROMAXX PERFORMANCEPART NUMBER: 723-3340
XXTREME Bare 240 cc Rectangle Port Cylinder Heads for LS1, LS2 w/4 in. Min. Bore w/63 cc Combustion Chambers
$1,63405
Ships on 09/21/2026
Lowest Price GuaranteeLS1, LS2 w/3.898 in. Min. Bore [240 cc Rectangle Ports]
XXTREME Bare Cylinder HeadsLS1, LS2 w/3.898 in. Bore 240 cc Rectangle Ports 63 cc Combustion Chambers Seats Installed for: 2.08 in. Int./1.60 in. Exh. Valves Valve Angle: 11° Requires LS3 Rocker Arms Set of 2
ProMaxx 3340 XXTREME Bare Cylinder Heads Features:
- High-flow as-cast port design
- Ultra-smooth 356-T6 aluminum casting
- 11-Degree valve angle
- Diamond honed guides
- Built-in raised valve cover rail
- .750 in. deck thickness
- For use with standard or 6 bolt pattern
- Large spring pockets
ProMaxx 3340 XXTREME Bare Cylinder Heads Notes:
- Requires 3.898 in. minimum engine bore
- Requires LS3 intake rocker arms
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
Part TypeCylinder Head
BrandPROMAXX PERFORMANCE
Part CategoryPerformance Parts
Cylinder Head MaterialAluminum
Exhaust Valves IncludedNo
Locks IncludedNo
Engine Make/SizeGM Gen III/IV LS
Retainers IncludedNo
Intake Port ShapeRectangle
Guideplates IncludedNo
Cylinder Head FinishNatural
Intake Valve Angle11
Valve Seat MaterialSteel
FinishNatural
Valve Springs IncludedNo
Valve Seat Machine Style5-angle
Cnc-Machined Intake RunnerNo
Intake Valves IncludedNo
QuantitySold as a set of 2
Valve Stem Seals IncludedNo
Accessory Bolt Holes DrilledYes
Valve Guide MaterialManganese bronze
Combustion Chamber Volume (Cc)63
Exhaust Valve Angle11
Rocker Arm Studs IncludedNo
Cylinder Head StyleBare
Part FitmentSemi Universal
Valve Cover Mounting StyleCenterbolt
Intake Runner Volume (Cc)240
Cnc-Machined Exhaust RunnerNo
Cnc-Machined Combustion ChamberNo
Vendor Part Number3340
Package Qty1
Package TypeEA
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