nwaimports.com
Dec-21st-03, 2:55 am
This is a simple guide to increasing car performance. This is for people that may be new to modifying vehicles, what may seem to be common sense may not be so obvious to others.
Air Intakes
Modifying a car’s intake system by replacing the stock air box for better sound and power is a common upgrade these days. Many major aftermarket companies make these intakes, which usually consist of a conical filter with a straight pipe leading to the intake manifold. The simple maxim “more air equals more power” applies to these systems, as they can take in much more air then the restrictive stock air box. However, there are two kinds of intakes to choose from, under hood and true cold air intakes. The under hood intake is one that sucks air from the engine bay itself, and while it can take in more air then the stock system, it is sucking in more hot air from the engine bay (another maxim applies here, “cold air always makes more power then hot air”). While longer, cold air intakes usually draw air from down by the fender wall (or any place away from the engine bay), they can also suck up water if you splash through as large puddle in the rain. This can obviously cause major damage, and is the only downside to a cold air intake. So before you look into either, weigh the benefits and risks. See my tips "How to make more power" and "Realistic power gains" for more information!
Camshafts for More Power
Upgrading your car’s camshafts is often a way to get significantly higher performance from the engine. In fact, there is almost no other single part in the engine that has a greater effect on its behavior then does the camshaft(s). To start off, there are three kinds of cam configurations: dual overhead cam systems (DOHC) have two cams, single overhead cam (SOHC) engine have one overhead cam and OHV engines have one cam that is not mounted in the overhead position. The cam controls the opening and closing of the engine’s valves, and is thus responsible for the intake of air and the expulsion of exhaust gases. These operations are measured in lift, the time the valve is off the seat, and duration, the time the valve is open. Obviously, the most air that can be taken into the engine and the more exhaust gases that can get out means more power. However, proper fuel and ignition timing must be supplied proportional to the new power. Also, if the cams have too high a light and duration for the street (nothing over 280 degrees of duration usually) low end power and idle quality will suffer. However, when tuned properly, upgraded cams can provide major power increases.
Exhaust Systems
Replacing the stock exhaust system with a more efficient aftermarket unit to gain more power and better sound is a common upgrade. However, there are many things to remember when you are looking for an exhaust system. Manufacturers often use the term “cat-back”, which simply means that their exhaust system replaces the stock unit from the catalytic converter back. Often, you will find a company not selling a complete exhaust system, but rather just the muffler. While this might give you a better exhaust note and cost less, it will generally not give you the same power increase a full cat-back exhaust would. It is always important to make sure that the exhaust system is emissions legal in your state. This information can be given to you buy any manufacturer. Noise is another important issue, as some exhaust systems may be too loud for your tastes, and can even be illegal because of noise pollution laws. Most cat-back exhaust systems, depending on the manufacturer, construction, and build material usually cost from about $200 to $1,000. Also, you should see my tip “How to make more power” and "Realistic power gains" for more information about the gains you can expect from an upgrade such as an exhaust system.
Headers
Headers have been a popular upgrade to get more power and better sound from your car for many years. A header actually replaces the stock exhaust manifold(s) with a more efficient and less restrictive system of tubular pipes. By increasing the efficiency of exhaust gas removal from the engine you can make more horsepower. However, there are many different designs of headers to choose from for different engine configurations, and the construction of each design can help the engine make more power in different places (such as one design might make more top-end power, while another might favor the low-end more). Also, the larger the engine, the more power a header will generally be able to make over the stock exhaust manifold. This is because the larger engine produces a greater volume of exhaust gases. Basically, a header on a Honda Civic won’t make the same kind of power that one would on a V8 Camero. Depending on the company, construction and material it is made form, a header(s) can cost anywhere from about $200 to $900. See my tips “How to make more power” and "Realistic power gains" for more information!
How to Make More Power!
The concept of making more power from an engine is very simple: an engine is basically a big air pump, and the more air you can take in, the more power you can make. Also, the more efficiently you can remove waste products (such as exhaust gases), the more power you will make. You can also think of an engine as a hose with a few kinks in it. If you free up one kink, water will not flow much better through the hose because there are still more kinks in the hose. This principle holds true for the engine as well, as it often has many restrictions. Lets say that you want to replace your stock air box with an aftermarket intake (see tip “Air intakes”), add a header (see tip “headers”) and replace the exhaust system with a free-flowing unit (see tip “exhaust systems”). If you only used one of these parts, say the intake, then you could not make as much power as if you used all of them. While this may seem very obvious, it is always good to remember that one part (such as the intake) might make only a few extra horsepower on its own. This is because there are still “kinks” left in the engine. However, power gains would be much higher if you got rid of all the kinks, allowing the parts to work together. See my tip "Realistic power gains" for more information.
Realistic Power Gains
Looking through a car performance magazine for upgrades can be very confusing. One part will claim 15 extra horsepower, this one will give you 20, and another promises 30. By the time you add it all up, you will be making more then 60hp over what you have now! This, however, is where most people get tricked… you will NOT be making that much extra power in most cases. Say you have an Acura Integra GS-R and you want to do a common intake (see tip “air intakes”), header (see tip “headers”) and exhaust system (see tip “exhaust systems”) upgrade. With these parts combined on a stock engine (lets assume that they are of high quality), you might make an extra 10 to 15hp at the wheels. While this isn’t the major 60+hp gain you were promised, it is still a noticeable increase in power. It is always important to stay realistic when looking for more power from your car. See my tip "How to make more power" for more information!
:thumbup:
Air Intakes
Modifying a car’s intake system by replacing the stock air box for better sound and power is a common upgrade these days. Many major aftermarket companies make these intakes, which usually consist of a conical filter with a straight pipe leading to the intake manifold. The simple maxim “more air equals more power” applies to these systems, as they can take in much more air then the restrictive stock air box. However, there are two kinds of intakes to choose from, under hood and true cold air intakes. The under hood intake is one that sucks air from the engine bay itself, and while it can take in more air then the stock system, it is sucking in more hot air from the engine bay (another maxim applies here, “cold air always makes more power then hot air”). While longer, cold air intakes usually draw air from down by the fender wall (or any place away from the engine bay), they can also suck up water if you splash through as large puddle in the rain. This can obviously cause major damage, and is the only downside to a cold air intake. So before you look into either, weigh the benefits and risks. See my tips "How to make more power" and "Realistic power gains" for more information!
Camshafts for More Power
Upgrading your car’s camshafts is often a way to get significantly higher performance from the engine. In fact, there is almost no other single part in the engine that has a greater effect on its behavior then does the camshaft(s). To start off, there are three kinds of cam configurations: dual overhead cam systems (DOHC) have two cams, single overhead cam (SOHC) engine have one overhead cam and OHV engines have one cam that is not mounted in the overhead position. The cam controls the opening and closing of the engine’s valves, and is thus responsible for the intake of air and the expulsion of exhaust gases. These operations are measured in lift, the time the valve is off the seat, and duration, the time the valve is open. Obviously, the most air that can be taken into the engine and the more exhaust gases that can get out means more power. However, proper fuel and ignition timing must be supplied proportional to the new power. Also, if the cams have too high a light and duration for the street (nothing over 280 degrees of duration usually) low end power and idle quality will suffer. However, when tuned properly, upgraded cams can provide major power increases.
Exhaust Systems
Replacing the stock exhaust system with a more efficient aftermarket unit to gain more power and better sound is a common upgrade. However, there are many things to remember when you are looking for an exhaust system. Manufacturers often use the term “cat-back”, which simply means that their exhaust system replaces the stock unit from the catalytic converter back. Often, you will find a company not selling a complete exhaust system, but rather just the muffler. While this might give you a better exhaust note and cost less, it will generally not give you the same power increase a full cat-back exhaust would. It is always important to make sure that the exhaust system is emissions legal in your state. This information can be given to you buy any manufacturer. Noise is another important issue, as some exhaust systems may be too loud for your tastes, and can even be illegal because of noise pollution laws. Most cat-back exhaust systems, depending on the manufacturer, construction, and build material usually cost from about $200 to $1,000. Also, you should see my tip “How to make more power” and "Realistic power gains" for more information about the gains you can expect from an upgrade such as an exhaust system.
Headers
Headers have been a popular upgrade to get more power and better sound from your car for many years. A header actually replaces the stock exhaust manifold(s) with a more efficient and less restrictive system of tubular pipes. By increasing the efficiency of exhaust gas removal from the engine you can make more horsepower. However, there are many different designs of headers to choose from for different engine configurations, and the construction of each design can help the engine make more power in different places (such as one design might make more top-end power, while another might favor the low-end more). Also, the larger the engine, the more power a header will generally be able to make over the stock exhaust manifold. This is because the larger engine produces a greater volume of exhaust gases. Basically, a header on a Honda Civic won’t make the same kind of power that one would on a V8 Camero. Depending on the company, construction and material it is made form, a header(s) can cost anywhere from about $200 to $900. See my tips “How to make more power” and "Realistic power gains" for more information!
How to Make More Power!
The concept of making more power from an engine is very simple: an engine is basically a big air pump, and the more air you can take in, the more power you can make. Also, the more efficiently you can remove waste products (such as exhaust gases), the more power you will make. You can also think of an engine as a hose with a few kinks in it. If you free up one kink, water will not flow much better through the hose because there are still more kinks in the hose. This principle holds true for the engine as well, as it often has many restrictions. Lets say that you want to replace your stock air box with an aftermarket intake (see tip “Air intakes”), add a header (see tip “headers”) and replace the exhaust system with a free-flowing unit (see tip “exhaust systems”). If you only used one of these parts, say the intake, then you could not make as much power as if you used all of them. While this may seem very obvious, it is always good to remember that one part (such as the intake) might make only a few extra horsepower on its own. This is because there are still “kinks” left in the engine. However, power gains would be much higher if you got rid of all the kinks, allowing the parts to work together. See my tip "Realistic power gains" for more information.
Realistic Power Gains
Looking through a car performance magazine for upgrades can be very confusing. One part will claim 15 extra horsepower, this one will give you 20, and another promises 30. By the time you add it all up, you will be making more then 60hp over what you have now! This, however, is where most people get tricked… you will NOT be making that much extra power in most cases. Say you have an Acura Integra GS-R and you want to do a common intake (see tip “air intakes”), header (see tip “headers”) and exhaust system (see tip “exhaust systems”) upgrade. With these parts combined on a stock engine (lets assume that they are of high quality), you might make an extra 10 to 15hp at the wheels. While this isn’t the major 60+hp gain you were promised, it is still a noticeable increase in power. It is always important to stay realistic when looking for more power from your car. See my tip "How to make more power" for more information!
:thumbup: