You can do a seemingly infinite number of things to modify your car, but
none alters it more radically in terms of horsepower and tone than your
exhaust headers. Your exhaust headers are the first part of your car that
exhaust travels through after exiting your engine’s cylinders, and
the way they are designed can have a huge influence over the way your
car’s engine runs. If you’re just starting out on your research
or aren’t familiar with how these parts work, then this Katy high
performance auto blog is for you: here is your complete primer on exhaust
headers, including how they work and what you should look for if you’re
considering them as an upgrade for your vehicle.
Key Components of an Exhaust Header Kit
To learn how an exhaust header upgrade works, it’s important to know
more about your entire exhaust system and learn how each part influences
the others in terms of performance, sound, and other vehicle specs. Here
are the key components to your exhaust, and a brief description each of them.
- Headers: these are a series of tubes which bolt to a flange on your cylinder
head and accept exhaust that pours out of the exhaust valves when they
open. The tubes eventually merge in to one single tube, which then passes
the exhaust back to the rest of your exhaust system.
Catalytic Converter: More commonly known as a “cat,” these
devices are designed to help regulate and reduce emissions outputs using
a variety of internal materials. In many cases, a catalytic converter
contains precious metals which it uses as a filter to help “scrub”
the air before it is released as exhaust.
It is illegal to tamper with, remove, or replace your catalytic converter
if your vehicle has less than 80,000 miles on it.
- Downpipe: Your downpipe connects your exhaust manifold with the main part
of your exhaust. Generally, this runs from the engine compartment down
to the bottom of your vehicle, which is where it gets its name.
- Mid-pipe: these are the pipes that run from the front of the car to the
rear, carrying the exhaust out to the back. Sometimes these pipes actually
cross or intersect, creating one of two different pipe patterns: an X-pipe,
or an H-pipe. Choosing one of these designs can both improve performance
and radically alter your car’s sound.
- Muffler: This is a device designed to help reduce the noise created by
your car’s engine by not allowing it to leave the tail pipe. Mufflers
are required by law, and can be found in a couple different places on
your car, though they’re usually located just back of the rear axle.
- Tip: An exhaust tip is both an aesthetic choice as well as a noise influencer.
The shape, diameter, and material of your exhaust tip will both influence
how your ride looks as well as modify the noise that is emitted from your
engine. Be sure to choose this carefully.
How Headers Work
Now that you know how these parts work, it’s fairly easy to understand
the difference an aftermarket set of exhaust headers can make for your
car. An exhaust header system is extremely important because you rely
on it to carry exhaust away so fresh air and fuel can enter so the cylinder.
However, the natural stroke motion of a piston head places the exhaust
under pressure as it leaves the cylinder, meaning the exhaust needs to
have the ability to flow out with as little resistance as possible.
This is where the engineering comes in: car manufacturers have to do everything
they can to reduce the amount of resistance exhaust experiences while
leaving the engine while still keeping the exhaust system compact and
inexpensive. Aftermarket exhaust headers take this problem and engineer
a solution that’s designed for a higher-performance vehicle. A good
set of exhaust headers will have a number of different factors taken into
First, the tubes attached to your cylinders need to be exactly the same
length when they meet up with the merge point. Having one tube be shorter
than the rest means that tube will be under lower pressure than the rest,
which means your engine will face uneven resistance. Uneven resistance
means more wear and tear on your engine and reduced horsepower.
Second, the length of the exhaust tubes dramatically influences the horsepower.
Headers usually come in three different lengths: long-tube, mid-length,
and shorty. Shorty and mid-length tubes will change your car’s tone,
but have lower power gains than a long-tube exhaust. As you might imagine,
long-tube systems are also the most expensive and toughest to install.
However, what all of these tubes have in common is that they are designed
to alleviate any back pressure from any exhaust that can’t flow
through and exit your exhaust system fast enough. Back pressure is any
exhaust that pushes back against the cylinder head as it forces the exhaust
out of the cylinder, and is a huge drag on your horsepower. By reducing
back pressure as much as possible, your engine will complete the exhaust
stroke with little to no resistance, allowing it to waste less energy
and every stroke can transfer more of its power directly to your wheels.
As a result, a good-quality exhaust system with well-engineered headers
can increase your horsepower by well over 100 in some cases.
Want to know more about your options for exhaust headers? Call the Katy
high performance auto experts at HP Motorsports today! Dial 281.231.9950 for a