Need help shifting a graph 180*

I'm making a spreadsheet for things engine/internal combustion related and, me being not the smartest, am running into troubles, simple stuff for a few of you I'm sure.

My basic question right now is this,

How do I shift this 180*?

Code:

`=Sheet1!$B$31*(COS(RADIANS(E4))-(($B$8/$B$6)*SIN(RADIANS(E4))^2)/(SQRT(1-($B$8^2/$B$6^2)*SIN(RADIANS(E4))^2)))`

B31= Dynamic Compression (this is what you measure with a compression tester)

E4= Crank Angle in degrees

B8= Crank Radius

B6= Rod Length

Guessing it's something rather simple and I'm just not seeing it.

Also will the answer work for shifting variations of a 720* total combustion cycle?

Say for a V8, V6, I4 ... each piston is at a different point in the cycle and thus a different point on the graph.

Hopefully this makes sense.

Thanks in advance for any assistance.

BTW, this isn't homework/school related, simply for my personal benefit.