To be a helpful standup guy like I am the way you adjust the airflow meter is cut the silicon that hold in the cap, then loosen the small screw that holds one of the wheels in there and then rotate the wheel very slowly. It should not take more than 4 teeth off to get what your going for. turning it one way makes you mixture more rich and one way makes it leaner. for more info on this mod check on pirate4x4 in the toyota faq under AFM trick or More Power. My motor is built up very simular to yours but I never did any of that and it runs pretty damn strong so you might have something else wrong