When you are trying to get more horsepower out of your engine there is one key thing to remember. More air = More power. Your engine takes in air and fuel then uses a fixed percent of air to fuel ratio combustion which give you power to crank up. There are several ways to add more power to your engine that I already talk about. The next thing I would like to share is the exhaust modification.
Exhaust system include headers, catalytic converter, exhaust and mufflers. Each part plays an important role in performance. Air resistance or backpressure makes it hard for exhaust fumes to exit a cylinder, and it robs your engine of potential power. When an exhaust pipe is too small or a muffler has a lot of air resistance, this can cause nasty backpressure. So, when you upgrade your entire exhaust system to one with larger pipes, you can eliminate this backpressure, therefore allowing air to exit more easily, and giving your ride a big boost in power.
It is very good if you can start with a good quality muffler. One of the easiest things you can do is to get rid of your power robbing stock muffler. Stock mufflers are designed to be as quiet as possible at the expense of horsepower. They are filled with twists and turns that the air has to go through that make them not straight through and awfully restrictive. Plus, they muffle the exhaust too much, and you don’t get the true performance sound from your car. A good quality pair of performance mufflers may set you back just under $500, but this is still a rather inexpensive way to add a noticeable gain in power.
Next to the muffler, the catalytic converter is the next biggest item on the exhaust that creates the most restriction. The stock catalytic converter is designed to catch as much of the exhaust as possible to ensure that as it flows through the catalytic converter that it trims all of the toxins as it exits. This is good for the environment and to keep smog pollution down, so replacing the catalytic converter can be done in two ways. The first way would be to replace it with a straight pipe. This simply gets rid of it all together. The other way would be to replace it with a high flow catalytic converter.
Aftermarket headers also have to do with reducing the back pressure of the exhaust. If you already have a cold air intake and an aftermarket cat-back exhaust system then you will feel the power this gives to you.