Here is an email I got from Hot Cams today when I asked about a 450 style cam for my 426: Yes we are working on cams for the 400/426 and 450 that will have the auto decompressor on the exhaust cam. It is not an easy project though, since all of our YZ cams have adjustable sprockets, and if you adjust the sprockets one way or the other to change the lobe centerlines, you have effected the decompressor weight positions. Anyway hopefully towards the end of the year we will have something. As soon as it is available, I will have them listed on the website. The price we are not sure of either at the moment, but they will be more expensive than the non decompression models. Let me know if you have any other questions.