hi guys i got a vz exec that i jus picked up got calis kit interior wat so eva on it from previous owner. its got the 175 kw engine. i want to improve the efficentcy of the engine soo it works much smoother and has a slight increase of power but the thing is im in a tight situation atm soo i dnt have big bucks to spend on mods wats the best way i can improve the engine performance abit without spending much thanx.....