from my knowledge, GT can handle a 50 shot with no engine thrashing and the GTS can handle a 75 shot.
I think your wrong, its the other way around, the stock gts cannot handle as much as nos as a stock gt can, the gt can handle almost 75, but the gts shoudnt be pushed with more than 50. The gts has waaayyyy too much compression to run a 75 shot safely, obviously no nos shot is safe, but like i said, 50 for gts and 75 for gt