System and method for variable valve timing

A variable valve timing assembly for a combustion engine comprises: a phaser configured to receive therein a camshaft; wherein the phaser includes a phaser exterior body that is cylindrical-shaped, a phaser interior body that is cylindrical-shaped and within the phaser exterior body, a phaser exterior spline on an exterior of the phaser exterior body, and a phaser interior spline on an exterior of the phaser interior body; a phaser inner housing disposed within the phaser and configured to receive therein the camshaft; wherein the phaser inner housing includes an inner housing interior spline that mates with the phaser interior spline; an advancing chamber configured to receive fluid from and discharge fluid to the camshaft; a retarding chamber configured to receive fluid from and discharge fluid to the camshaft; and a main housing that encloses therein the phaser and the phaser inner housing, and is configured to engage a timing chain/belt.