The new rear tires are a considerable harder compound tire (580 vs. 140) than the stock tires were and therefore less traction. Since you only changed the rears you now have a handling imbalance because of different tire compounds front vs. rear.
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'11 370Z Nismo #528 Fast Intentions | Stillen | Motordyne | Uprev | CSF | Zspeed | Z1 Motorsports | AST | Swift | SPC | SPL | Whiteline | Hotchkis | Bride | Schroth | Robispec | Cusco | Nismo | Volk | Forgestar | Hoosier | RJM
'17 Titan Bone Stock
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