It really depends on your power level as the OP touched on. As you crest 650 WHP you’ll start to see soaring OEM cat temps and less efficiency from the engine. That’s about the point where you should seriously consider headers & high flow cats (or no cats… for off road use only, since the EPA is probably reading this  ).
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2017 Chevy Camaro 2SS A8 Whipple 3.0, Mast Black Label heads, ATI 8L90, Fore triple in-tank pumps, 112mm TB, LPE +52% injectors & BB HPFP, TooHighPSI/Katech port injection, 15” conversion 1066 WHP STD/1027 SAE, 9.10@152.5 (new times coming)
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