Ls has a larger stroke by 1.8mm (LS=89mm, GSR/ITR/B16=87.2mm)
The first things I would do with an LS/V is 1, a girdle. No point in revving high without one. 2 being pistons/rods. Whether they're aftermarket or just stock ITR/CTR/PR3, anything is better than the stock LS pistons/rods. And obviously some supporting mods like cams, an lsd transmission, built head, etc.
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