I forgot to add the bit about bending over 90 degrees. I will cover this bit in one page then crack on with the headers bit.
First thing to do is pull the 90 bend out of the port and lets say it has to angle forward to gain length before turning back to the collector. With a random piece of pipe mark the centerline of the return to the collector.
Next hold up a protractor to find the angle and lock it in at that.
Hold the angle finder on the bender as per photo, we are still working on center to center . Then pull the bend to suit the angle finder.
Perfick
The same applies for anything that goes into the bender at whatever angle.
Bob