The "041" Ram Air IV cam w/ 1.5:1 rockers is widely considered to be "THE" cam to have in a street driven Pontiac. It was the first "computer designed" Pontiac cam in 1969, and Edelbrock validated this profile by copying it after extensive testing for their RPM cam some 20 years later. It has alot of low end torque and will still rip your head off in the midrange. It has a lopey idle at 550 - 600 RPM, but still has enough vacuum for the power brakes. And if .470 lift isn't enough, a set of 1.65 rockers will put you at .517. Competion Cams also has a RA IV grind in the "Muscle Car Cams" section of their catalog. This is probably the best until someone comes up with a hydraulic roller. The three digit numbering scheme is nothing more than the last three digits of the actual part number. Hence the "041" really type "T" as mentioned in the previous question. Stock, the 455 manual cars used the 068 cam and the automatic cars used the 067 cam.