If you're building a Nissan 240SX and want more power without going fully catless, the ISR Performance High Flow Catalytic Converter is the middle ground that actually makes sense. You get less restriction than the factory cat, a more aggressive exhaust note, and you're still converting harmful exhaust gases. No compromise required.
What It Is
The ISR Performance High Flow Cat is a direct-fit catalytic converter replacement for the Nissan 240SX. It uses a 300 cell spun metallic substrate, which flows significantly better than the stock unit. The metallic substrate is more durable than ceramic alternatives and handles higher exhaust temperatures, making it a better match for modified engines like the SR20DET or KA24DE with bolt-ons.
What It Does
The stock catalytic converter on the 240SX is restrictive. It was designed to meet emissions standards from the early 1990s, not to support a modified engine making more power than factory. The ISR High Flow Cat reduces that restriction while still functioning as a catalytic converter. The result is improved exhaust flow, a measurable bump in horsepower and torque, and a noticeably deeper, more aggressive exhaust tone compared to stock.
Fitment and Compatibility
This high flow cat is designed for the Nissan 240SX (S13 and S14 chassis). It bolts directly to the factory exhaust system with no modifications needed. It also bolts up to aftermarket exhaust systems, as long as the aftermarket exhaust was built to OEM flange specs. If you're running a test pipe or straight pipe and want to add a cat back into the system, this is a direct swap.
Who This Is For
This part fits a few different builds. If you're running a street-driven 240SX and want better flow without going catless, this is the move. If you're putting together a drift car that still needs to pass a basic visual inspection, it checks that box. And if you've already done intake and exhaust work and the stock cat is your remaining bottleneck, swapping to the ISR High Flow Cat is one of the easier gains left on the table.
Product Details
Brand: ISR Performance
Product: High Flow Catalytic Converter
Vehicle: Nissan 240SX (1989-1998, S13 and S14)
Substrate: 300 cell spun metallic
Installation: Direct bolt-on, factory or OEM-spec aftermarket exhaust
Key Benefits: Increased exhaust flow, improved horsepower and torque, more aggressive exhaust tone, emissions conversion retained