you can make them easy by hand in a drop saw you take of the clamp bit and get a long pc of angle line and bolt it down on a very steap angle towards your body if you are doing it for a 6cyl you divide 6 into 360 which is 60 then you divide that by two 30 because you make to cuts take a cut then get a prtractor and mark of your 30ddegs of the flat side of the cut then cut that repeat 6 times an you should have a 360deg colector with a point in the midile i have made heaps and they turn out awesome ill try and get some pics up for you