Got this out of the Engine Master Challenge 2003.

"The cylinder heads are Chapman CNC-ported Mopar Performance Stage VI heads (PN 4532885), with Max Wedge port sizes. For big-block Mopar guys, this is about as good as it gets in a factory-replacement head."

http://www.popularhotrodding.com/enginemasters/challenge/2003/0405phr_emc3/index.html