
PROMAXX PERFORMANCEPART NUMBER: 723-3169
XXTREME Assembled 260 cc Rectangle Port Cylinder Heads for LS3 w/4 in. Min. Bore w/59 cc Combustion Chambers
$3,46571
LS3 w/4 in. Min. Bore [260 cc Rectangle Ports]
XXTREME Assembled Cylinder HeadsLS3 w/4 in. Min. Bore 260 cc Rectangle Ports 59 cc Combustion Chambers 2.165 in. Int./1.60 in. Exh. Valves Valve Angle: 11° Valve Springs: .800 in. Max Lift Retainers: Tool Steel Set of 2
ProMaxx 31698 XXTREME Assembled Cylinder Heads Features:
- High-flow as-cast port design
- Ultra-smooth 356-T6 aluminum casting
- 21-4N stainless 1 piece swirl polished back cut valves
- 5-angle valve job
- 11-Degree valve angle
- Hardened steel valve seats
- OEM LS3 valve spacing
- Manganese bronze diamond honed guides
- Viton valve seals
- Built-in raised valve cover rail
- .750 in. deck thickness
- Billet LS3 OEM rocker stand
- For use with standard or 6 bolt pattern
- Large spring pockets
ProMaxx 3169 XXTREME Assembled Cylinder Heads Notes:
- Requires 4 in. minimum engine cylinder bore
- Requires LS3 intake rocker arms
- Included valve springs for solid roller cam with tool steel retainers specs:
- .800 in. Maximum valve lift
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
Extreme Performance for LS Engines that Won't Break the Bank
ProMaxx EXXTREME Series aluminum cylinder heads for GM LS engines have runners and combustion chambers designed for maximum airflow.
Part TypeCylinder Head
Product LinePromaxx XXTREME GM LS Aluminum Cylinder Heads
BrandPROMAXX PERFORMANCE
Part CategoryPerformance Parts
Cylinder Head MaterialAluminum
Exhaust Valves IncludedYes
Locks IncludedYes
Engine Make/SizeGM Gen III/IV LS
Retainers IncludedYes
Intake Port ShapeRectangle
Guideplates IncludedNo
Cylinder Head FinishNatural
Intake Valve Angle11
Maximum Valve Lift0.8 in (20.32 mm)
Valve Seat MaterialSteel
FinishNatural
Valve Springs IncludedYes
Valve Seat Machine Style5-angle
Cnc-Machined Intake RunnerNo
Intake Valves IncludedYes
QuantitySold as a set of 2
Valve Stem Seals IncludedYes
Intake Valve Diameter2.165 in (55 mm)
Accessory Bolt Holes DrilledYes
Valve Guide MaterialManganese bronze
Combustion Chamber Volume (Cc)59
Exhaust Valve Angle11
Rocker Arm Studs IncludedNo
Cylinder Head StyleAssembled
Part FitmentSemi Universal
Valve Cover Mounting StyleCenterbolt
Retainer MaterialTool steel
Intake Runner Volume (Cc)260
Cnc-Machined Exhaust RunnerNo
Cnc-Machined Combustion ChamberNo
Exhaust Valve Diameter1.6 in (40.6 mm)
Vendor Part Number3169
Package Qty1
Package TypeEA
No Questions
No Reviews
Items You Need
Some parts are not legal for use in California or other states with similar laws / regulations

![GM LS Rocker Arm Bolts [8 mm x 1.25]](https://www.jegs.com/images/mini_200/500/555/555-83485.jpg)


![Valve Spring Compressor [Stud Mount]](https://www.jegs.com/images/mini_200/500/555/555-80518.jpg)
![Valve Spring Compressor [Stud Mount]](https://www.jegs.com/images/mini_200/500/555/555-80521.jpg)
![W89409 Valve Spring Compressor [C-Style]](https://www.jegs.com/images/mini_200/500/555/555-w89409.jpg)
![Engine Assembly Lube [4 oz. Bottle]](https://www.jegs.com/images/mini_200/500/555/555-28000.jpg)



![Precision Cam Degree Wheel Kit [11 in.]](https://www.jegs.com/images/mini_200/500/555/555-81621.jpg)




![1/2 in. Drive Torque Wrench [10 to 150 ft. lbs.]](https://www.jegs.com/images/mini_200/500/555/555-m200db.jpg)

![Breaker Bar [1/2 in. Drive, 30 in. L]](https://www.jegs.com/images/mini_200/500/555/555-w32126.jpg)
![Deep Well Impact Socket Set, 1/2 in. Drive [SAE 11-Piece]](https://www.jegs.com/images/mini_200/500/555/555-m590db.jpg)
![Deep Well Impact Socket Set, 1/2 in. Drive [Metric 11-Piece]](https://www.jegs.com/images/mini_200/500/555/555-m591db.jpg)