For engines built before 1996, these catalytic converters have stainless steel ribbed bodies that minimize expansion/distortion when the converter heats up. The ribs form a channel that protects pads from direct exposure to exhaust gas, plus they keep the ceramic catalyst aligned. Rigid OE-type heat shields add structural stability, and strong 1/2" lap-joints fuse necks to the body (for best flow, necks don't extend into bodies). .
2. Determine the type of catalytic converter being replaced:
Choosing the Correct Catalytic Converter
1. Determine engine size and vehicle weight (there are legal limit regulations).
Note: 49-State Catalytic Converters are not legal for sale, installation, or use on licensed vehicles in the state of California.
Is there a big improvement to the flow of air compared to a stock?
WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.
WARNING: Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Some examples of these chemicals are: lead from lead-based paints, crystalline silica from bricks and cement and other masonry products, and arsenic and chromium from chemically treated lumber. Your risk from exposure to these chemicals varies, depending on how often you do this type of work. To reduce your exposure, work in a well-ventilated area and with approved safety equipment, such as dust masks that are specially designed to filter out microscopic particles.
WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.