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NK Performance and Racing

AFR Mongoose 260CC LS3 CYLINDER HEAD

AFR Mongoose 260CC LS3 CYLINDER HEAD

Regular price $3,095.95 USD
Regular price Sale price $3,095.95 USD
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Block Configuration
260cc LS3 Cylinder Head

AFR’s 260cc LS3 "Mongoose" heads feature 100% CNC ported intake, exhaust and chambers using our advanced engineering and flow techniques to produce the ultimate Rectangle Port head available today. Featuring A356 aluminum castings, titanium retainers and the highest quality components, throughout. They’re designed for 4.000 or larger bore applications up to 454 CI, operating up to 7000 RPM. This product is street legal in 50 states from 2007 to 2016 emission controlled vehicles with a General Motors 6.2L LS engine. AFR heads are available bare (without parts), call our tech line for details.
 

Basic Package Components
100% CNC Ported Combustion Chambers
100% CNC Ported Exhaust Ports
100% CNC Ported Intake Ports
Competition 5-angle Valve Job

 
8mm Bead Lock Intake Valve, 2.165" x 5.200" Overall Valve Length
8mm Bead Lock Exhaust Valve, 1.600" x 5.205" Overall Valve Length
PAC Racing Spring 1.270" OD Hydraulic Roller Dual Valve Spring, 155 lbs. on seat, .650 maximum lift, Max RPM 7000-7200
7° Titanium Retainers 1.245" O.D x .885" I.D x .655" I.D
7° Bead Lock Valve Keepers
Viton Valve Seals .600" O.D x .495" I.D
Hardened Valve Spring O.D Locator 1.380" O.D x .570" I.D
Ductile Iron Intake Valve Seats 2.200" O.D x 1.750" I.D x .375" Deep
Ductile Iron Exhaust Valve Seats 1.650" O.D x 1.350" I.D x .375" Deep
8 mm Bronze Valve Guides .502" O.D x 2.550" O.A.L
Rocker Rail Stand
AFR #6040

 

260cc Large Bore Competition Flow Chart
  .200 .300 .400 .500 .600 .650 .700
Int 159 234 293 336 366 377 384
Exh 112 158 207 235 248 251 255

Test conducted at 28" of water (pressure) on Superflow 1020
Bore Size: 4.060", intake 3/4" radius plate exhaust, 1 3/4" curved pipe

 


Specifications & Features:
Material
A356 Aluminum
Intake Port Volume
260cc
Intake Port Dimension
2.610"H x 1.300"W x 7/16° Radius
Intake Port Location
Stock
Exhaust Port Volume
95cc
Exhaust Port Dimension
1.540" H x 1.760" W
Exhaust Port Location
Stock
Combustion Chamber Size
69cc
Valve Cover Bolt Pattern
Center Bolt
Valve Angle
12°
Valve Spring Pocket Diameter
1.490" O.D
Max Valve Spring Pocket Machining
1.510" O.D
Warning: Do not machine spring pad any deeper.
Deck Thickness
.750"
Minimum Bore Diameter
4.000"
Flat Mill - 65cc chamber
.006" per cc 62cc Maximum
Minimum Cross Sectional Area
2.875 sq. in.
Spark Plug Dimensions
14mm x .750" w/ Tapered or Gasket Seat
Carb EO#
 
Recommended Components:
Intake Port Gasket
Factory GM or Aftermarket
Recommend Rockers - OEM w/ trunion upgrade Yella Terra 6733 w/ 5132 Valve Cover gasket.
Scorpion 1162
Exhaust Port Gasket
GM #12558573
Head Gasket
Cometic 4.160 Bore Size
Head Bolts (04+), ARP 134-3610
Head Studs (04+), 2004 & Later Blocks ARP #234-4317, Pre 2004 Blocks ARP #234-4316
Head Bolt Washers, Manley
Suggested Manifold
FAST 92mm or 102mm
Spark Plug Starting Range
NGK TR55
Pushrods: Longer than Stock (see instructions for details)
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