mr.86

I'm facing an issue with my custom made air filter which i bought separately with a tube and k&n air filter n mounted the airflow sensor on it, the power and the sound is great but when the rpm goes around 3000 to 4000rpm it gives a knocking sound in the engine or even when acceleration in the beginning and later at the point of changing gear i tired adjust almoat everything in my knowledge dint workout, if anyone has any idea what and where the problem i would need your suggestions. thank you