Question about how to degree my cam

Do what Bbrroomm said above, the 108 is the number you'll be working with. If you want to know about the-1.5, do the math. Total degrees of duration is added up as 180 + the event opening degrees BTDC + the event closing ABDC = total degrees at .050 So you have 34.5 plus 180 plus a (negative) 1.5 = 213 degrees at .050. The negative in this example is because the card states BTDC, BUT in this case it's not occurring at BTDC it's actually occurring ATDC, so to keep the math in check , a double negative is required.