I have always measured cam timing when I have 0.060 of lift on the lifter itself.
This figure eliminates the opening and closing ramps on the cam lobe.
Your figures show a normal 293 cam.
As far as it being 4 degrees advanced...I doubt that Jasper...(or any mass production rebuilder), would custom grind a cam plus 4 degrees....
The usual mechanism to install a cam plus or minus is to use a special upper gear and an offset bushing to move the cam itself. There are kits around that have a lower gear with three keyways cut, one straight up, one plus 5 and one minus 5.
The accuracy of these figures is always assuming there is zero slop in the cam chain and gear set...
Even a new set often has up to 3-4 degrees crank of slack....thats why performance engines usually use a precision gear set.
Have fun....
