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AFR - Airflow Research 1846

260cc LS3 Mongoose Street Aluminum Cylinder Heads LS Chevy Block


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Estimated ship date 12/28/17 if Ordered Today
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AFR - Airflow Research 1846 260cc LS3 Mongoose Street Aluminum Cylinder Heads LS Chevy Block $2,097.14
260cc LS3 Mongoose Street Aluminum Cylinder Heads
  • LS 4-Bolt Chevy Blocks
  • 69cc Combustion Chambers
  • Rectangle Intake Port
  • Bare Head Only
  • Sold in Pairs, 2/pkg.

  • AFR - Airflow Research 1846 Details

    LS Blocks

  • Four Head Bolts Per Cylinder

    This is an unassembled bare cylinder head with valve guides and valve seats installed only. Does not include any parts such as valves, springs, spring components, studs or guideplates.

    LS Chevy 260cc LS3 Mongoose Basic Package Components
    100% CNC Ported Combustion Chambers
    100% CNC Ported Exhaust Ports
    100% CNC Ported Intake Ports
    Competition 5-Angle Valve Job
    Intake Valve Size, 2.165" x 5.195" O.A.L. (Valve not included)
    Exhaust Valve Size, 1.600" x 5.200" O.A.L. (Valve not included)
    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
    LS Chevy 260cc LS3 Mongoose Street Head Specifications
    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.
    Deck Thickness 0.750"
    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/Gasket Seat
    Carb EO# D-250-5
    Intake Port Gasket Factory GM or Aftermarket
    Exhaust Port Gasket GM #12558573
    Head Gasket Cometic 4.160 Bore Size
    Head Bolts (04+) ARP 134-3610
    Head Studs (04+) ARP 234-4317
    Head Bolt Washers Manley
    Suggested Manifold FAST 92mm or 102mm
    Spark Plug Starting Range NGK TR55
    Rocker Arms Use full roller rocker arms, roller tip rockers with stock style bodies are NOT recommended.
    Pushrods Different length pushrods might be required, always check pushrod length. Check pushrod clearance with heads placed on the block before final assembly. Larger pushrods will not fit without clearancing and is not recommended since some areas are very thin. AFR recommends the use of .120" thick-wall pushrods.
    Spring Installation To ease installation with 1.550" O.D or larger springs, 12 pt head bolt or studs are recommended for extra clearance. Beveled or ground washers might be needed (ARP #200-8504 comes with smaller O.D and doesn't need to be ground)

  • Modeled After the GM LS7 Aluminum Head

    AFR's 260cc LS3 "Mongoose" heads feature 12° valve angle, 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 cubic inches, operating up to 7000 RPM. Emissions legal for 2008 to 2015 vehicles under CARB #D-250-5.

    260cc LS3 Mongoose Street Cylinder Head Features:
  • 100% CNC Ported Combustion Chambers
  • 100% CNC Ported Exhaust Ports
  • 100% CNC Ported Intake Ports
  • Competition 5-angle Valve Job
  • 260cc Intake Ports, Stock Location (2.610" Tall x 1.300" Wide x 7/16° Radius)
  • 95cc Exhaust Port, Stock Location (1.540" Tall x 1.760" Wide)
  • 69cc Combustion Chambers
  • 8mm Bead Lock Intake Valve, 2.165'' x 5.195'' Overall Valve Length
  • 8mm Bead Lock Exhaust Valve, 1.600'' x 5.200'' Overall Valve Length
  • PAC Racing Valve Springs: 1.270'' OD Hydraulic Roller Dual Valve Spring, 155 lbs on seat, Max RPM 7000-7200
  • 7° Titanium Retainers 1.245" O.D x 0.885" I.D x 0.655" I.D
  • 7° Bead Lock Valve Keepers
  • Viton Valve Seals, 0.600" O.D x 0.495" I.D
  • Hardened Valve Spring O.D Locator, 1.380" O.D x 0.570" I.D
  • Ductile Iron Intake Valve Seats
  • Ductile Iron Exhaust Valve Seats
  • 8mm Bronze Valve Guides, 0.502" O.D x 2.550" O.A.L
  • Rocker Rail Stand
  • CARB E.O. # D-250-5

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