I went from unresonated FI exhaust with cats and switched to TPs. Crazy difference in noise; I like it. The stock cats are quiet af compared to open flow. No experience with HFCs tho :shrug:
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed |
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