When you degree a cam, it is relative to crank degrees.
Normally, you would install a cam "straight up" in accordance with the manufacturers recommended intake lobe centerline angle (the point of crank rotation at which max valve lift is achieved). If straight up was at say 108 degrees of crank rotation, this is where max valve lift would occur. If you advance the cam 4 degrees, then max lift would occur at 104 degrees of crank rotation - in other words, max lift occurs earlier relative to crank rotation.
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Some cam manufacturers grind their cams with built in advance. Sometimes there is as much as 4 degrees, sometimes only one degree to take into account some timing chain stretch.
It is not uncommon for the straight up position to be off from the cam card spec due to machining tolerances in the associated parts - thus, the reason for checking the installed position with a degree wheel.
If you feel the installed position is lacking in bottom end performance, you may want to try a little cam advance. Advancing the cam results in closing the intake valve earlier and helps build cylinder pressure and torque. Advancing a cam may also lower peak power output due to an associated reduction in max rpm. Retarding a cam from the straight up position is usually of no benefit to peak power as it delays the intake valve closing point, and thereby reduces cylinder pressure and power across the rpm range.
Be careful about adding too much advance as it cold cause excessive cylinder pressure that may result in detonation in an engine with a high static compression ratio. You should also check for adequate piston to valve clearance as advancing the cam starts the valve opening cycle sooner - meaning the intake valve is open further when the piston is at TDC.
