If you're chasing more flow out of the exhaust on your Infiniti Q60 3.0T but you don't want to gut the catalytic converters entirely, the ISR Performance High Flow Cats are built to thread that needle. They use a less-restrictive 300-cell metallic substrate to free up power while still converting harmful exhaust gases, and they're fully TIG welded with true mandrel bends throughout. They bolt up to your factory or aftermarket exhaust, retain the factory oxygen sensor location, and add a more aggressive tone in the process.
What It Is
The ISR Performance High Flow Cats are a pair of custom-made stainless steel catalytic converters for the Infiniti Q60 3.0T. Each one uses a 300-cell spun metallic substrate that flows more freely than the restrictive factory units, while still housing an active catalyst that converts harmful exhaust gases. They're built with full TIG welds and true mandrel bends, and they retain the factory oxygen sensor location so the car's sensors stay where they belong.
What It Does
A high flow cat replaces the restrictive factory catalytic converter with one that lets exhaust gas pass through more easily, which is where the power gains come from. Unlike a test pipe or cat delete, a high flow cat keeps a working catalyst inside, so it continues converting harmful gases rather than dumping them straight out. On the twin-turbo Q60 3.0T, reducing exhaust restriction helps the turbos breathe out more freely, and the lower cell density also opens up a more aggressive exhaust tone than the muted factory setup.
Why 300-Cell Metallic Substrate
Cell count refers to how many channels per square inch run through the catalyst honeycomb, and a lower number means larger, less crowded passages for exhaust to flow through. Factory cats typically run a higher cell count for maximum emissions conversion, which also makes them more restrictive. The 300-cell metallic substrate here strikes a balance: enough catalyst surface to keep converting gases, but open enough to reduce the restriction that costs you power. The metallic substrate also handles heat and flow better than the ceramic substrate found in many stock converters.
Construction Quality
These cats are fully TIG welded, which produces cleaner, stronger, and more consistent welds than the alternatives, and that matters on a part that sees constant heat cycling. The true mandrel bends keep the pipe diameter consistent through every curve rather than crimping and narrowing at the bends, so the exhaust gas keeps flowing without hitting pinch points. Both are the kind of construction details that separate a custom-made piece from a mass-produced one.
Bolt-On Fitment and Factory Sensor Retention
The ISR High Flow Cats bolt up to your factory exhaust, and they'll also bolt to an aftermarket exhaust as long as that exhaust is built to OEM specs. They retain the factory oxygen sensor location, so your sensors thread back into their original spots without relocation or extension. That keeps the install straightforward and avoids the sensor-placement headaches that come with some less thoughtfully designed pieces.
Fitment and Compatibility
These high flow cats are designed for the following:
- Infiniti Q60 3.0T
They bolt to the factory exhaust or to an aftermarket exhaust built from OEM specifications. The factory oxygen sensor location is retained. Confirm your exhaust matches OEM dimensions before purchasing if you're running an aftermarket system.
Who This Is For
These cats fit a specific owner. If you want to free up exhaust flow and pick up power on your Q60 3.0T while keeping working catalytic converters in the car, this is built for that middle ground. If you want a more aggressive exhaust tone without going to a full cat delete, the 300-cell substrate gets you there. If you value build quality and want fully TIG welded, mandrel-bent cats that retain your factory sensor location, this is the part for that.
These are not the right cats if you're looking for a full cat delete or test pipe, since these retain an active catalyst by design. They're also not the pick if your local emissions rules require factory or certified converters, in which case you'll need to confirm what's permitted where you drive before buying.
What's in the Box
- 2x Stainless steel high flow cats
- 3x 2-bolt exhaust gaskets
- 1x 3-bolt exhaust gasket
- 9x Bolts
- 9x Nuts
Emissions and Legality
Verify your local emissions regulations before purchasing or installing. High flow catalytic converters are not guaranteed to be 50-state legal, and they may not be compliant in states with strict emissions requirements such as California. It is the buyer's responsibility to confirm what is permitted for street use in their area. Check your local and state regulations before buying.
Installation Notes
Professional installation is recommended. The cats bolt into place using the included gaskets and hardware, and they retain the factory oxygen sensor location, so the sensors thread back into their original positions. Let the exhaust cool completely before working on it, transfer your oxygen sensors carefully to avoid damaging the threads, and check all connections for leaks after the first heat cycle. If you're installing onto an aftermarket exhaust, confirm it's built to OEM specs so everything lines up.
Product Details
Brand: ISR Performance
Product: High Flow Catalytic Converters
Part Number: IS-HFC-Q60
Vehicle Fitment: Infiniti Q60 3.0T
Material: Stainless steel
Substrate: 300-cell spun metallic
Construction: Fully TIG welded, true mandrel bends
Oxygen Sensor: Retains factory location
Exhaust Compatibility: Bolts to factory or OEM-spec aftermarket exhaust
Legality: Verify local emissions regulations; may not be 50-state legal
Key Benefits: Less-restrictive 300-cell metallic substrate for power gains, retains active catalyst to convert exhaust gases, fully TIG welded with true mandrel bends, retains factory oxygen sensor location, more aggressive exhaust tone, bolt-on fitment