If the motor is new I don't recommend running synthetic. 10w30 Castrol or your preferred brand is good and number 8 or 9 ngk gapped to about 25 thou. Spark plug gap also depends on how much boost you are running. My buddy has a 2.0 turbo with about 45 psi. Made 710 whp. He runs Castrol 10w30 and NGK 9 gapped to 18 thou!