I don't have an older Z, nor do I have the stock bolts, but the bolts that were sent by Z1 are 3". I hope this helps in some way...
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Competition Clutch|Fast Intentions|Maxbore|NST|Setrab|Stillen|Tomei|Uprev| Z1
Avant Garde|SPC|Stance|Whiteline
Aerojacket|Seibon|Tanabe|TRS|TWM
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