I got welded on boxed subframes a few days ago, and I could tell the diffence only because on the way there, there was a rough section of highway, and on the way back, on that same section, the car drove much better, it hit the bumps better, and it also takes off-ramps (90 degree or bigger) faster and with less "flex"...
mine is a SN-95, and while it was stiff, its stiffer now. and, it DEFINATELY launches differently now.. but mainly, its just small improvements.. since they are so cheap, they're worth it I think...
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94 GT (triple black)
FMS 95 17" Cobra R's / AL Driveshaft / 3.27's
K&N, 190 lph, subframes, pulleys
MAC Shifter/Gauges/Pedals, Euro Clear Projectors & Corners
My CAR!