Would someone help me to understand what effect the different angles on the helix bring to the party. If I have a straight 55 in now and I install a 55/53 or 55/52 in the sled what would this do? When do you need the double helix and when do you stay with the single angle? What happens when you increase or decrease the angle on the single helix? How do you know when you have gone too far? Where can I find a book or artical on this subject?Thanks for the help.