Finding the right cylinder head for a smaller bore build has always been a bit of a headache for the LS community. You usually have to choose between reworking tired factory castings or spending a fortune on aftermarket options designed for much larger engines. Air Flow Research (AFR) has finally addressed this gap with their new CNC heads for LS engines, which are designed specifically to wake up the 4.8-liter and 5.3-liter platforms without breaking the bank.
The foundation of this new package is the Mongoose family cylinder head casting poured from A356 aluminum. This material choice provides a robust starting point that is significantly stronger than a standard OEM head. AFR engineers then applied their CNC porting process to every single inch of the intake runner, exhaust port, and combustion chamber. The 214cc intake runners are the star of the show here because they smooth out the airflow path from the manifold all the way to the valve. This precision machining improves cylinder fill and combustion efficiency to create a potent combination for any street machine or tow rig.
Real-world performance was obviously the goal during development. These heads deliver a strong midrange torque curve that transitions seamlessly into stable top-end power up to 6,500 rpm. Durability is also a major factor since many of these engines see boost or nitrous. The deck thickness measures a stout 0.750 inch to handle that extra cylinder pressure with total confidence. The valvetrain comes ready to rock with high-quality components like Pacaloy hydraulic roller springs and Viton valve seals.
AFR has fitted 2.00-inch stainless intake valves and 1.570-inch exhaust valves, both with 8mm valve stems with a single bead lock retainer groove. Builders should note that the bead lock valve locks are specific to GM LSX specifications and are not interchangeable with other aftermarket locks. These heads flow
This package supports engine combinations up to 383 cubic inches and offers a bolt-on solution that does not compromise drivability. It effectively eliminates the need to gamble on junkyard parts or overspend on race-spec gear. The new CNC heads for LS engines simply offer the reliable airflow and modern technology that 4.8-liter and 5.3-liter owners have been waiting for.
You might also like
EngineLabs Tool Of The Month: Speedway Motors’ BlockDock
The unsung heroes of the shop, this new line of BlockDock lift plates and engine cradles are high-end tools to move and store your engine.
