I have the Strange Engineering unit. It is expensive and I am not even sure if it is any different than the Mopar unit but man does my car stop fast for basically a stock brake system. The Strange cylinder is used in conjunction with a stock '73 A-body brake system. IIRC it is a .125" bore.

Ryan "Bigs" '73 Duster (BLKDUST) - Black, 100% factory sheet metal, flat hood, 346 cid, J Heads, and a bench seat. http://s268.photobucket.com/albums/jj1/bigsbigelow/ Best to date: 12.40 @ 109 mph