It doesn't have a "Chevy" cam. It has a camshaft for a HEMI or it wouldn't fit in the motor. And while the cam may not be ideal, it is not likely what is causing it to be way down on power. A .600ish lift cam with 260 and 268 @.050 on a 110 is not out of the ball park for a street ride. Now the cam could be installed wrong and seriously hurt power, but it is not down on power just because of the cam grind. A STOCK cam in a 484" HEMI should make more power than this one seems to.

You also say it slowed even more on the last outing. Are you sure the trans or converter is not hurt?

Monte