I understand that the LLY has and EGR valve on it and i am curious as to if the LB7 has one or not. I am trying to make my LLy as loud as my LB7. I have the cat and muffler cut off the LLY and the muffler off the LB7 and it is still louder you can hear it from miles away. If the EGR in any way affects the amount of noise the truck can make is there anyway that you can safley remove it?

The 6.0L PSD has EGR and is much much louder. I dont see EGR cutting down noise.

Just a guess but the quietness of the LLY vs the LB7 could have to do with the LLY being tuned to pass the new emission requirements.