Ok, I bought a set of Black Magic pipes off ebay about a year ago for my 440. I received the pipes and can, but soon realized it was not the correct setup for my snowmobile. I called black magic and ended up concluding they are not really for a 440, maybe something more along the lines of a 500 or 600. So I basically got screwed, and I can't really sell them because I don't honestly 100% know what they are, and I wont screw someone over like that. The guy from black magic said that the pipes are essentially the same, but the can is different. So, does anyone here know what the inside of a performance can looks like? Pictures would help if possible. Any 2-stroke pros in here know how much back pressure a 440 would need, or any calculations on how to come up with a can that would be suitable for me? I know I'm asking a lot, and that this will probably take a lot of research, but I figured I'd start here. Any comments or suggestions would be greatly appreciated, thank you all.