The MK Design lower intake manifold will replace the factory lower intake manifold on the LFX 3.6 V6 motor.
 
Short runner version will be 3/4"  longer than the factory lower intake manifold.   This will broaden the powerband and give a decent bump in torque.
 
Long runner version are for those wanting to go all out.   The long runner version will also also the front wheel drive LFX motor to use the rear wheel drive intake manifold on their motors.