...assuming you use the aluminum version of the LS engine...
Funny thing: the iron block adds about 80lbs. While I'm all for aluminum, iron blocks are SO much less expensive that it'd almost be worth it.
Relocating the battery to the back of the car would offset half of that.
Is it worth it? Check this out:
(I think that's Tony's car)
Blue-ish 2006 2.4, Werks stage 1 turbo, Borla cat-back, DDM braces, Spec aluminum flywheel, Spec stage 2 clutch, Werks aluminum radiator, some gauges, RKSport hood, Morimoto FX-Rs, GReddy Profec, Norm's fenders
'07 GXP, Werks Big Wheel K04 and tune, Solo catless downpipe, TCE Wilwood 6 piston front brakes, 4-piston rears , stainless brake lines, slotted/drilled rotors, BC Racing BR coilovers, Performance Autowerks intercooler, DDMWorks CAI, charge pipes and braces, RPM rollbar