AFR 15° LS Cathedral Port Cylinder Head 215cc Fully CNC Ported, 65cc Chambers, Large Bore

The AFR 215cc LS1 Mongoose cylinder head is designed for moderate street or street/strip builds with displacements up to 408 cubic inches, operating at or below 6500 RPM. This medium-sized, high-velocity torque monster flows an impressive 312 CFM @0.600" of lift, ensuring excellent performance for your LS engine build.

Included 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, 2.020” x 4.900" Overall Valve Length (AFR #7207)
8mm Bead Lock Exhaust Valve, 1.600” x 4.900" Overall Valve Length (AFR #7228)
PAC Racing Spring 1.290" OD Hydraulic Roller Dual Valve Spring, 140 lbs on seat, .600" maximum lift, Max RPM 6300-6500, less than 235° duration (AFR #8017)
7° Titanium Retainers 1.245" O.D x .885" I.D x .655" I.D (AFR #8512)
7° Bead Lock Valve Keepers (AFR #9007*)
Viton Valve Seals .600" O.D x .495" I.D (AFR #6612)
Hardened Valve Spring O.D Locator 1.380" O.D x .570" I.D (AFR #8042)
Ductile Iron Intake Valve Seats 2.131" O.D x 1.680" I.D x .375" Deep (AFR #9059)
Ductile Iron Exhaust Valve Seats 1.650" O.D x 1.350" I.D x .375" Deep (AFR #9069)
8mm Bronze Valve Guides .502" O.D x 2.100" O.A.L (AFR #9051)

*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.

215cc Competition Flow Chart

Lift	.200	.300	.400	.500	.550	.600
Intake (CFM)	149	215	259	293	300	303
Exhaust (CFM)	111	150	209	225	230	233

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: 215cc
Exhaust Port Volume: 85cc
Combustion Chamber Size: 65cc
Valve Angle: 15°
Deck Thickness: .750"
Minimum Bore Diameter: 3.900"
Flat Mill: .006" per cc 58cc Maximum
Minimum Cross Sectional Area: 2.260 sq. in.
Spark Plug Dimensions: 14mm x .750" w/Gasket Seat

Performance & Compatibility

This AFR 15° LS Cathedral Port Cylinder Head is engineered for performance-focused LS builds and is not legal for sale or use on emission-controlled vehicles. It is intended for dedicated race applications only.