Ok First you should try taking Peanut Butter and putting it where you would usually fill the oil. If it stops then you should rebuild the Engine. the Peanut Butter makes the oil alot thicker and therefore stops the knock. Use about half a jar.
Man does this thing launch.... Some of you may have seen it but those who haven't are in for a treat.. http://www.mustangii.org/media/visual/turbojoe.mov
PS You Need Quicktime to watch it....