Yeah, what's the better engine? All around. I'm curious.

 

LS1. The can be thought of as a factory "heads and cam LT1" just like much like the LS6 copares to the LS1. The Gen III motors were an all new design, superior to any Gen II motor, case closed.

Now, between the 2 in an F-body, theyre both going to put down similar rwhp, so if you are to leave the car stock, its really just a matter of preference. Once you mod, its all about how deep your pockets are.