High Flow Catalytic Converters

While regular catalytic converters are quite effective, they often restrict the flow of exhaust. This can rob the car of valuable power. For car enthusiasts, there is a balance that must be struck with maximizing power while minimizing the possibility that customization may make the car illegal to be on the street. This is where high flow catalytic converters come in. These types of catalytic converters maximize the flow of exhaust as much as possible while still removing the toxic pollutants. It’s the closest thing you can get to not having a catalytic converter at all and still be able to pass an emissions test.

High flow catalytic converters increase a car’s horsepower by a slight margin. About 5 hp is the common increase, and while that doesn’t seem like much, the horsepower increases with further engine modifications, such as turbo charging. The horsepower increase is more noticeable at higher RPMs, when the car is emitting the most exhaust fumes. This increase over the basic catalytic converters may be enough to get some people to switch, if only to recapture the horsepower lost by using a normal catalytic converter. The increase in torque is also only mildly noticeable at high RPMs.

In the maximization of exhaust output, the main concern of most car owners is the ability for high flow catalytic converters to clean up exhaust fumes enough to pass an emissions test. Virtually all high flow catalytic converters are sold as “49-state legal”; that is, they’re legal to use and will pass emissions tests in 49 states. The only state where they won’t is California, where the emissions standards are much more stringent than those in the rest of the country. If you’ve ever wondered why the cars given away on the California-based game show “The Price Is Right” usually have “California emissions” in their descriptions, this is why; these cars are equipped with converters that will pass California’s very high emissions standards. High flow catalytic converters that are legal to be sold in California are a rare breed, and these converters will outperform most regular catalytic converters.

High flow catalytic converters are one of the aftermarket items of choice for car lovers wanting to squeeze a few more RPMs and horsepower out of their vehicles without having to do major, and costly, engine upgrades. That being said, aftermarket companies are trying to find ways to improve their high flow converters so they’ll be able to pass California emissions standards. Otherwise, the 49-state legal converters are the best ones out there—if you don’t live in California, that is.