but what i do not understand is if the CG a young arnold , why didn't they CG the punks that were at Griffith park as well? why are they different punks did something alter their lives as well when the 1st terminator even further back in time to save young sarah ?
They are in another timeline now.
In this timeline, the punks you remember from Terminator 1 with their mohawks and trenchcoats took their studies much more seriously and became actors instead of hanging out late at night harassing people.
Punk nr 2 got a great gig playing Ian Mitchell-Smiths older brother and later on a soldier on a journey to a distant plant called LV-423, and Punk nr 3 got a very lucrative career, playing a Conqueror of Dimensions, a bodyguard to a Vampire among other roles.
A ripple in time can change alot and make waves.
Instead of punkin' around, they became respected actors at an early age.