This is handy if you want to put a big carb on your stock av10 cases. I put a 21mm on and it was quite zippy.
Word of caution though, the casting is rough and I had to file a lot of the flat surfaces down in order to get an acceptable seal. I also used a teeny bit of gasket maker where the o-rings join up as I would occasionally get leaks from there.
Another word of warning for this is those 3 little black bolts that screw in and do a sandwich type fit - like to fall out. I had to blue locktite them in order to keep them from backing out and causing air leaks. Do NOT use red on that part. You will be going down a trail of tears.
fun times ahoy 
