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NK Performance and Racing

AFR Mongoose 245CC LS1 CYLINDER HEADS

AFR Mongoose 245CC LS1 CYLINDER HEADS

Regular price $3,069.71 USD
Regular price Sale price $3,069.71 USD
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Chamber Volume
Exhaust Valve Upgrade

Our max effort cathedral port head for the LSX platform is recommended for race applications or radical "Pro Street" builds with displacements up to 454 cubic inches, operating at or below 6800 RPM. Requires a minimum bore size of 4.000" to clear the supplied 2.165" intake valve. CARB Legal for 2005 and older emissions controlled vehicles under CARB EO #D-250-4 with 65cc combustion chambers.


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 4.900" Overall Valve Length
8mm Bead Lock Exhaust Valve, 1.600" x 4.900" 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 2.100" O.A.L


*LSX bead locks and aftermarket bead locks are not interchangeable. GM made their bead lock radius and depth different. AFR locks are the same as GM LSX.

245cc Large Bore Competition Flow Chart
  .200 .300 .400 .500 .550 .600 .650
Int 164 233 290 332 347 356 360
Exh 131 185 227 247 249 257 267

Test conducted at 28" of water (pressure) on Superflow 600
Bore Size: 4.155", intake 3/4" radius plate exhaust, 1 3/4" curved pipe


Specifications & Features:
Material
A356 Aluminum
Intake Port Volume
245cc
Intake Port Dimension
3.315"H x 1.145"W x 11/32 top 13/32 bottom
Intake Port Location
Stock
Exhaust Port Volume
88cc
Exhaust Port Dimension
1.495" H x 1.730" W
Exhaust Port Location
Stock
Combustion Chamber Size
65cc or 73cc
Valve Cover Bolt Pattern
Center Bolt
Valve Angle
15°
Valve Spring Pocket Diameter
1.510" O.D
Max Valve Spring Pocket Machining
1.525" O.D
Deck Thickness
.750"
Minimum Bore Diameter
4.000"
Flat Mill - 65cc chamber
.006" per cc 58cc Maximum
Flat Mill - 73cc chamber
.006" per cc 65cc Maximum
Minimum Cross Sectional Area
2.680 sq. in.
Spark Plug Dimensions
14mm x .750" w/Tapered Seat
CARB Status: This product is not legal for sale or use on emission-controlled vehicles and intended for dedicated race vehicles only.
 
Recommended Components:
Intake Port Gasket
GM or FAST
Exhaust Port Gasket
GM #12558573
Head Gasket
Cometic 4.200 .040" or AFR #6845
Head Bolts (97-03)
ARP 134-3609 or AFR #6330
Head Studs (97-03)
ARP 234-4110 or AFR #6331
Head Bolts (04+)
ARP 134-3610 or AFR #6334
Head Studs (04+)
ARP 234-4317 or AFR #6335
Head Bolt Washers, Manley
Suggested Manifold
FAST 90mm, 92mm, or 102mm
Spark Plug Starting Range
NGK TR55
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