subject: A Guide To Honda Civic Exhaust Systems [print this page] There are a number of things to consider when upgrading your Honda Civic exhausts. To begin with I recommend that you set some goals by working out exactly what you want to achieve. Are you looking for the biggest increase in power possible, a great sounding exhaust, or something in between.
When Honda builds their cars they need to comply with a multitude of government regulation depending on what country the car is to be released in. These rules often cover noise and emissions and consequently the exhausts system is designed in a way which is complies with them. The result is small exhausts systems which are extremely restrictive and limit the amount of power of an engine will produce. They are often in the case of Civic's severe bottleneck which limit the performance of the vehicle.
The first things your need to upgrade is the header. This is the section of piping where the exhausts gasses from each cylinder and combined into a single pipe. There are two main types of exhaust headers for 4 cylinder Honda's and they are 4-2-1 and 4-1. In a 4-2-1 system the four tubes combine into 2 tubes which then combine into 1 whereas in a 4-1 system the 4 tubes combine into 1 tube at a single point. The differences in design mean that power will be delivered in a different way. 4-2-1 systems are best for mid range power whereas 4-1 systems will make the most top end power.
After the header comes the catalytic converter, a part designed purely to reduce emissions. Any good aftermarket high flow cat will be a good upgrade and can net up to 5hp (more if yours is old and clogged up).
Further back comes the cat-back or b pipe. Commonly people upgrade to larger diameter piping as this can free up some horsepower. Your muffler is also included in this system and it is vital to have the right type of muffler if you want your car to sound good.
By upgrading all the component of the Honda Civic exhausts system you should be able to see some impressive gains when it comes to horsepower as well as sound. Now go and show off that system!
