One day, you are riding your beloved car and you see your friend is riding the same car with a louder sound. So, now you are thinking about adding high-flow cats instead of your stock cats. An opposite thing can happen. You might think about going with no cats. So, what is the difference between a high-flow cat vs no cat?
A high-flow cat can decrease the toxic elements from exhaust gases, increase horsepower and make your exhaust sound louder with a fine tune. With no cats, your exhaust gases will not be filtered and there will be some odor while accelerating.
In this article, we will discuss high flow cat vs no cat comparison and will see how they will affect the performance of your vehicle.
Comparison Table of High Flow Cats and No Cats
We will see a short summary of using high-flow cats and no cats. We took 4 important factors for comparison.
Key Factor | High-flow Cats | No Cats |
---|---|---|
Engine power | Can increase | Can Increase |
Fuel consumption | Reduce fuel consumption | Increase in some cars |
Fuel filtration | Better filtration | No filtration |
Sound | Louder sound | Engine sound will increase |
Benefits and Problems with High Flow Cats
High-flow catalytic converters are an excellent car modification. They enable exhaust gases to flow more freely since they are not as restrictive as standard catalytic converters.
This may assist increase horsepower while also improving fuel efficiency. A high-flow cat may be just what you need to increase the performance of your car. But there are some issues as well.
Benefits of High-Flow Cats
Increased Power
When blocked with dust and trash, the catalytic converter may slow back the car’s performance. A high-flow catalytic converter allows more air to leave the exhaust system, making way for additional air. Airflow boosts horsepower.
Improved Fuel Consumption
High-flow catalytic converters may minimize fuel consumption. Better ventilation and horsepower will help your engine consume less petrol. This means fewer gas station trips and greater savings.
Inexpensive
If you’re concerned about the expense of installing a high flow catalytic converter, you may relax knowing that it’s far less expensive than purchasing a brand-new stock catalytic converter.
Best 2 High-Flow Catalytic Converter
Autosaver88 ATCC0007 Catalytic Converter

New universally suited catalytic converter from AUTOSAVER88 is engineered to match or even surpass OE functionality and performance requirements.
To expand the response area and make sure there are enough catalysts (Pt, Rh, and Pd) on the surface layer for greater conversion efficiency, inbuilt honeycomb ceramic foundations feature porous structures.
Flowmaster 2230130 Catalytic Converter

These top-notch catalytic converters are made in the USA and have an exterior shell made of stainless steel for optimal durability.
For optimal efficiency and to prevent “MIL” code problems that are typical with lower-quality converters, the interior substrate material and precious metal loading have been meticulously developed.
Problems with high-flow cats
Ignite Check Engine Signal
If the catalysts in the rectifier have to be changed or are not working correctly, the check engine signal will come on. Additionally, a defective oxygen sensor may cause your check engine signal to come on.
Odor Can be Felt
When you are operating your automobile in slow gear or even at a low rpm, you could notice an exhaust stench. The catalyst converter begins burning gasoline when it becomes too hot, which is the cause of the exhaust odor.
Louder Sound
Your car’s emission system may change its sound, becoming loud and harsh, thanks to a high-flow catalytic converter. This is dependent upon the size of your exhaust and the kind of pipes your car has.
Benefits and problems with no cats
Benefits of no cats
Engine Efficiency Improved
This is feasible due to the fact that the catalytic converter generates a substantial amount of back-pressure on the engine. Because it minimizes the effect of the departing gases, removing it allows them to leave the engine quicker and in higher quantities.
Extended Fuel Options
You may be able to access additional fuel choices if you remove the catalytic converters. You have the option of using the high-performance fuels that are now readily available on the market.
Increased Mileage
Due to the catalytic converter’s restrictive qualities, removing it reduces the load on the engine. When the converter is still in place, the engine will no longer need to run at twice its normal rate to generate the same amount of energy.
Problems
Illegal to Remove
It is illegal to remove it, and even if you just really want to, you may have to undergo into a bunch of legal formalities. It’s against the law to tamper with or remove a functional catalytic converter, and the consequences may amount to large numbers of dollars.
Will Not Pass the Test
Catalytic converter-less vehicles will categorically fail their emissions testing and will not be eligible to extend their permits. Testers must record this error if the catalytic converter is not present because it is mandated by law.
Read Also: 9 Pros And Cons Of High Flow Cats
FAQ
What’s Better High-Flow Cats or No Cats?
You cannot get the answer straight as there are some legal and requirement aspects. If you want to be safe from legal issues, emission test issues and clean exhaust system, high-flow cats are the best option. If you don’t care about the legal issues and need increased engine power with no air filter, then the no cat will be best.
Are High-Flow Cats Louder Than No Cats?
Though the high-flow cats will increase the sound of exhaust from stock cats, removing the cats will increase the sound more than high-flow cats. When you have no cats, the sound will be louder as there is nothing to suppress the gases coming from the engine.
Are High-Flow Cats Are Effective?
High-flow cats cost less than conventional cats and perform more. They circulate more air, giving your machine more horsepower. High-flow cats are lighter and bigger than regular cats, making your automobile seem nimbler.
Final Thoughts
Finally, the decision is yours. As there are some legal aspects, before going for any cats options, consider your local laws. Though the high-flow cats are more environment friendly, fuel economy and legal than no cats.