that bottom end torque of the ls will get overwhelmed by the top end of the gsr if the drivers are equal .... my friend beat me when i first got my gsr in his ls , but i missed 3rd gear , but i spanked that ass by like 6 cars every run since then .... he can only HANG with me thru most of 2nd and i start to pull away alot !! Im not dissing the ls , but your mods prolly havent got you up to his stock hp #'s