Hey ,well after a couple of problems , my rockers are on the car , thanks to the combined efforts from the guys at Mace , and to the boys at my local Holden Dealer , particularly Graeme the service manager , and technician Aaron , it's all good to go , took it for a proper run this morning , and with my other mods ,and the rockers it has a more punch at the mid to high range , enough to give a small push back in the seat , it seems more ready to rev as well . Here is a list of the mods to the car - in no particular order .
69mm polished throttle body
PCM tune , because my auto played up a bit
12mm plenum spacer
12mm manifold insulator
82 degrees thermostat
SS Growler induction
high ratio rockers , with push rods ( those with a VX may have the same problems as the VY )
polished rocker covers
thermo wrapped headers
2.5 sports exhaust