Question about the V-8 in the E430

Why is it that the E430's V-8 produces 295 lb/ft of torque, will BMW's 4.4 liter V-8 and Lexus' 4.3 liter V-8 both produce around 325 lb/ft? I know the BMW and Lexus engines have timing on both the intake and exhaust cams, but what about the E430, does it only have timing on the exhaust valves? That could be one reason. How much horsepower and torque does a sopisticated valve/cam timing system usually add, around 10 horsepower and 10 lb/ft?