Restrictive Exhaust
A restrictive exhaust creates backpressure in the exhaust system that hurts your vehicle's performance in two ways:
- The engine has to work harder to force exhaust gases out of the cylinders.
- Engines cannot scavenge burned exhaust gases out of the cylinder efficiently. This leaves exhaust gases in the cylinder to dilute incoming air/fuel mixtures and rob your engine of horsepower.
Pipe Diameter
A common misconception is that the larger the diameter, the better the system. But, bigger isn't always better. Systems that are too large in diameter can actually hurt performance. As a general rule, switching to a performance system that is 1/4 to 1/2 inch larger than stock will provide you with the best horsepower increases. To determine which pipe diameters will be best for your system, decide what RPM range your engine will operate at, most of the time. Smaller diameter pipes will produce low- to mid-RPM torque. Larger diameters produce mid-to high RPM torque.
Horsepower Depends on Flow, not Pipe Diameter Alone
Bigger isn't always better. Systems that are too large in diameter can actually hurt performance. Improved flow is what you need. Having large diameter pipes isn't what's cool. Going fast and making horsepower is.
X-Pipes
X-Pipes help to even out the pulses in the exhaust gases and balance the backpressure between both banks of your engine. They not only help improve horsepower, but sound as well.
To find the right location to install your X-Pipe, apply a strip of paint down the front portion of the exhaust pipes. The X-Pipe should be placed where the paint burns off (bubbles) on the exhaust pipes. Generally, put the balance tubes as close to the headers as possible. The X-Pipe diameter should be at least 75% of the diameter of the pipes with which it connects.