The 674-933 Exhaust Manifold Converter includes a direct replacement kit designed to replace the factory installed exhaust manifold on a Nissan Altima.
This kit is designed as an exact-fit replacement for the 2007-2012 Nissan Altima L4 2.5L engine, matching the OE part number 14002-JA91E. Because this is a manifold-to-header connection, having the correct hardware is vital to ensure a leak-resistant seal that can withstand high-heat cycles. We selected this unit for our comparison because it provides a direct bolt-on solution that avoids the need for custom welding or fabrication. While the kit serves as a direct replacement, the documentation does not explicitly state the inclusion of specific torque specifications or thread-locker requirements, so you should verify these with the manufacturer’s support page before beginning the installation. Additionally, while the unit is a leak-resistant manifold and catalytic converter, it is not CARB approved and cannot be shipped to or installed on a vehicle in the state of California.
What to Check Before Buying the Altima Exhaust Manifold
Before purchasing this converter, confirm these technical details to ensure the part fits your specific vehicle configuration and meets your local requirements.
You can view how the Altima Exhaust Manifold compares to other options in our full review.
- Verify that the kit includes all necessary gaskets and mounting bolts for the manifold-to-header connection to avoid extra trips to the hardware store.
- Confirm the presence of the oxygen sensor bung to ensure your existing sensor can be reattached without a separate adapter.
- Check for specific torque requirements for the mounting studs to prevent snapped bolts or exhaust leaks during heat expansion.
- Ensure your vehicle is not a California emissions-equipped model, as this unit is not CARB approved and cannot be used in that state.
- Confirm that the manifold geometry matches your engine block casting to avoid port mismatch where the exhaust tubes do not align with the cylinder ports.
Comparing the Altima Exhaust Manifold to Other Options
The Altima Exhaust Manifold serves as a direct replacement for a vehicle’s primary exhaust flow path, which is the function of an exhaust manifold catalytic converter. This specific product is suited for owners who prioritize an exact-fit, bolt-on solution over aftermarket high-flow ceramic substrates. If you require a converter that meets California’s strict emissions standards, you would need to look at alternatives, as this specific model is restricted to non-CARB regions. Buyers seeking a high-performance upgrade might also consider different substrate materials, but for a standard 2.5L engine replacement, this kit provides the specific geometry required for a factory-style fit.
If you own a 2007-2012 Nissan Altima 2.5L and need a direct, leak-resistant replacement that avoids custom fabrication, you should choose this product.
For off-road builds, explore our top-rated exhaust manifold catalytic converter for jeep wrangler options.
Nissan Altima 2.5L Exhaust Manifold Catalytic Converter
See our full comparison of the best exhaust manifold catalytic converter for hyundai santa fe sport for more details.
$152.99 price checked August 2026
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