i've always been told ls is better for turbos and gsr is better for all motor so if all motor is your plan then I would say gsr.
GSR (gsr head/ gsr block)
LS/VTEC (gsr head/ ls block)
LS (ls head/ ls block)
i've always been told ls is better for turbos and gsr is better for all motor so if all motor is your plan then I would say gsr.