hey man, sure the gli would withstand NOS, but be sure to replace the original pistons wid new titanium ones, they cost arnd 60,000 for FOUR !!!!......the original piston would withstand the heat n the pressure of nos, but not for long, becase the nos burns at a very high tempt. it'll melt the old pistons, titanium ones can withstand tht sort of pressure..........lemme kow how it turned out..laters