Pinion angle for a street cruiser
To eliminate vibration, it is important match the total amount of U-joint angles of the front u-joint and / rear u-joint
example....
1) differential angled DOWN 3.5 degrees MINUS (same angle) driveshaft DOWN 1.0 .................equals total 2.5 degrees
2) engine angled DOWN 1.5 degrees PLUS (opposite angle) driveshaft angled UP 1.0 degree......equals total 2.5 degrees
when the angles match, smooth as silk. stay away from a straight line / no angles