Introducing the baddest valvetrain parts for your G8X
 
One piece forged black nitrated stainless intake valves and sodium filled inconel valves for the exhaust side.
Match these valves with #supertech springs and titanium retainers, you will be on your way to an indestructible motor. 
 
12 Sodium Inconel Valves
12 Stainless Intake Valves
1 set of 5/6mm billet keepers
24 Beehive springs and titanium retainers
24 Valve seals