Go to Corral - there's a thread running about the BBK manifold test in this month's 5.0 Mustang's and Fast Fords (or some such mag) and how bogus the test protocol was. It's an improvement over the stock intake - but only at rpm's higher than most street driving occurs. Most folks in that thread seemed pretty disappointed in the results, but most disappointed in the way the mag tested it. http://www.corral.net/forums/showthread.php?t=558600