Dynamic Compression and Aluminum Heads?

AND AGIN Y CANT I PRINT INFO ABOUT HEADS I MAY BUY FROM MCG> ? ON THERE ADD 440 SOURCE. there heads sound and $ r good but cant print add 4 info to take 2 my shop 2 get ck out. why r they wrong . got $. DOES MCG AND 440 source make $ whit a nut as me. y cant I print spec"s on their product MY$...…………………………….. and solid. as a vet...……………..100% shot