MagnaFlow 333105 CARB Universal Cat: Fit and Rules
By MagnaFlow Exhaust, Mufflers & Cat Converters - Quality | Published: 2026-11-03
Category: How-to Guides
Learn how to check fit and follow California rules before installing the MagnaFlow 333105 CARB compliant universal catalytic converter, with a step-by-step process.
Quick answer
To install the MagnaFlow 333105 CARB compliant universal catalytic converter legally and correctly, first verify that your vehicle is covered by its California Air Resources Board (CARB) Executive Order, then confirm pipe diameter and space before welding it in place.
Why the 333105 is not a one-size-fits-all solution
The MagnaFlow 333105 is a universal catalytic converter, meaning it is designed to fit a wide array of vehicles rather than a specific make and model. That flexibility comes with a tradeoff: you must confirm that the part's CARB Executive Order (EO) explicitly lists your vehicle's year, make, model, and engine. Without that match, the converter is not California legal, even though it is CARB compliant in general.
Universal converters also require fabrication skills. The 333105 does not come with vehicle-specific flanges or hangers, so you will need to cut and weld exhaust pipe. If you are not comfortable with welding or exhaust work, budget for a professional installation.
What to check before you buy
Before ordering, locate your vehicle's emissions label (often under the hood) to confirm it is a California emissions vehicle. Then visit MagnaFlow's website or call their tech line to verify the 333105 EO covers your exact configuration. Also measure your existing exhaust pipe diameter at the converter location; the 333105 is designed for a specific inlet/outlet size, and using adapters can create leaks or flow restrictions.
If your vehicle is not listed in the EO, you cannot legally install this converter in California or other states that have adopted CARB rules. In that case, look for a direct-fit CARB converter that matches your vehicle.
Step-by-step installation and compliance check
- Verify CARB EO coverage: Find the EO number for the MagnaFlow 333105 (it is typically on the product page or included paperwork) and check that your vehicle's year, make, model, and engine are listed. Common mistake: assuming that because the converter is CARB compliant, it is legal for every car. If your vehicle is not listed, do not install it in California; choose a direct-fit CARB converter instead.
- Measure pipe diameter and space: Use a caliper or pipe gauge to measure the outside diameter of your existing exhaust pipe where the converter will go. Also check for clearance around the converter location, as the 333105 has a compact low-mass design but still needs room for welding and heat shielding. Common mistake: ordering without measuring, then finding the pipe size is incompatible. Write down your measurements and compare them to the 333105's specified inlet/outlet size before cutting anything.
- Prepare the exhaust and test-fit: Disconnect the battery, raise the vehicle safely, and support it with jack stands. Cut the old converter out, leaving enough straight pipe on both sides for the new unit. Test-fit the 333105 in place, checking that it does not contact heat-sensitive components and that the inlet/outlet arrows (if present) point in the direction of exhaust flow. Common mistake: cutting too close to bends, leaving no room for welding. Mark the pipe alignment with a marker before welding to avoid misalignment.
- Weld and seal: Tack-weld the converter in place first, then check alignment and clearance again before completing the weld. Use a MIG or TIG welder suitable for stainless steel; the 333105's stainless construction and single laser fusion weld reduce leak risk, but your welds must also be leak-free. Common mistake: using mild steel wire, which can rust and fail emissions. After welding, reinstall any oxygen sensors and check that all fittings are tight.
- Perform a leak check and test drive: With the engine cold, start it and listen for exhaust leaks around the welds. Then take a short test drive and confirm the check engine light does not come on. The 333105 is designed to keep the check engine light off when installed correctly. Common mistake: skipping the leak check, which can cause poor performance and failed emissions tests. If the check engine light stays on, recheck oxygen sensor connections and scan for codes before assuming the converter is defective.
Product facts
- MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 333105: CARB compliant universal catalytic converter with stainless steel construction and single laser fusion weld. The stainless steel resists corrosion, and the single weld reduces leak risk, but you still must verify the EO covers your vehicle.
MagnaFlow California Grade CARB Compliant Universal Catalytic Converter 333105
