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You are using an out of date browser. It may not display this or other websites correctly. You should upgrade or use an alternative browser. Thread starter fattea Start date Oct 7, For those of you who haven't installed any long tubes before here is a some what detailed list of how to perform the install, I can't provide pictures with this because I did take any while installing them, but Im not gonna lie its a pain in the ass.
It took me arount 10 hours to do the install from start to finish. You need help so get a buddy for this install. I installed pacesetter long tubes on my car. I will give a list of steps on how to perform this install 1. Next you need to remove the steering bar on the drivers side, What you do is turn your steering wheel to a 90 turn to the left the bottom of the steering wheel will point exactly to the passenger side door what this does is aligns the bolt that holds the steering bar facing up so you can get a socket with at least 12 inches of extention on the bolt.
Remove the bolt, make sure you tie up your steering wheel so it doesn't move, this can damage the springs in the wheel. I tied mine off to the emergency brake 4. Jack the car up as high as you and put stands underneath 5. Remove the Stock H pipe and cat set up this requires a 15MM deepwell socket and a U joint up by the stock manifords, next 15MM socket at the mid pipe connection on the band clamps, smack these back with a hammer and the rear pipes will drop 6.
Underneath the car, you have to remove the rest of the steering bar, make sure you mark the bar down there so putting it back in wont be so hard to remember. Go inside the car underneath the dash behind your pedals in the steer bar from the inside unbolt the 2 bolts on the firewall that keeps the bar from moving.
Unbolt the motor mount, doesn't matter what side you do first, if you start on the driver side, unbolt that side completely, and loosen the other side but don't take off all the way.
This will prevent the motor from going and drifting on you. Just leave a few threads on the passenger side 9. Get a piece of wood and place it under the oil pan you are going to need to jack the motor up until the motor mount clears the bolt you just took off. Well, yes and no, as the power output of the motor is determined by the amount of airflow any engine can process. By process, we mean ingest air and fuel, burn the mix efficiently, and then expel the burnt gasses with minimal emissions.
With that, more airflow from an individual component may or may not increase the amount of air actually processed by the motor. A perfect example of this would be the installation of a dual 75mm throttle body on an otherwise stock 4. The larger throttle body will certainly outflow the stock throttle body, but the motor can't take advantage of the additional airflow since the stock throttle body didn't represent a restriction at stock power levels.
This situation changes when we add a supercharger, but only once we reach a given power output which translates directly into an airflow measurement. In this example, if we see vacuum present behind the throttle body at wide-open throttle, a larger throttle body will likely improve the power output. Simple airflow devices such as a throttle body or even an after-cat exhaust are fairly straightforward, but more complicated are components like camshafts, intake manifolds, and the subject of this test long-tube headers.
In truth, this test involved both headers and an after-cat exhaust, but the significant midrange power gains came from the scavenging effect of the long-tube headers. Unlike air filters or throttle bodies that allow enough air past or not, cams, intakes, and headers have a decided tuning effect on the power curve. Camshaft timing dictates at which engine speed the motor will be most efficient, with higher-duration cams dictating higher engine speeds. Intake manifolds work much like long-tube headers in that longer runner lengths primary lengths on the header are optimized for lower engine speeds, while shorter lengths promote power higher in the rev range.
The same can be said of runner diameter or cross section , as larger runners or primary diameter pipes for headers will increase the optimum engine speed. That is to say, a 2-inch by inch primary header pipe will be optimized at a higher engine speed than a pipe that measures 1. This tuning effect has nothing to do with the actual flow rate, as the diameter and length determine the travel speed of the resonance waves.
Primary pipe length and diameter are but two of the many variables that can affect the performance of a set of headers. Before getting to the test, perhaps a brief explanation of how this resonance occurs will shed some light on how difficult it is to produce the proverbial "ideal" or "best" set of headers for any given combination.
More than simple exhaust flow, true headers promote power production through two effective means of scavenging. In simplified terms, scavenging occurs when both the intake and exhaust valves are open a position referred to as camshaft overlap.
The outgoing exhaust flow helps draw in intake mixture by creating a low-pressure zone in the combustion chamber. This scavenging effect helps introduce more intake air and fuel mix, which allows the motor to make more power. And this relatively simple scavenging effect is accomplished through two somewhat sophisticated mechanisms-the first being the kinetic energy of the outgoing gases. Since we lack the space for a detailed description of exhaust theory, we will have to revert to the Reader's Digest version.
The opening of the exhaust valve produces a compression pulse. The release of this compression pulse creates high pressure in front of the wave but a depression on the backside of the wave. Since the speed of this wave exceeds that of the exhaust gas flow through the pipe, the depression or low-pressure zone produces a scavenging effect.
The second method of scavenging produced by the long-tube header is called reflected wave scavenging. Once the pressure pulse has been released by the opening of the exhaust valve, the wave travels the length of the exhaust pipe. Upon reaching the end of the pipe typically the collector , something magical happens. The positive pressure wave is allowed to expand into the relatively larger collector.
This expansion causes a momentary drop in density of the air surrounding the end of the primary pipe. The elasticity of the air causes it to rebound toward the pipe exit. This creates a new negative pressure wave that then travels back up the primary pipe to the awaiting exhaust port. This reflection of the positive and negative pressure waves continues indefinitely, though the waves decrease in amplitude or effective strength.
For optimum performance, the exhaust-pipe length should be selected to produce the primary first order reflected negative pressure wave at its lowest pressure when the piston just passes TDC at the end of the exhaust stroke. Since these waves travel at the speed of sound which is pressure and temperature dependent , tuning this event for a specific engine speed requires changing the length of the primary pipes.
Short primary runners employed on stock exhaust manifolds don't allow sufficient time for the compression wave to leave behind a depression capable of improving scavenging. The short primary lengths also promote early arrival of the reflected wave, which minimizes effective intake and exhaust scavenging. It's important to note that no header yet produced is optimum for all combinations.
The laws of physics dictate otherwise, as the scavenging effect of the headers is initiated by the opening of the exhaust valve, which is also dependent upon the overlap-which is also dependent on the reflected waves produced by the intake design.
You can see that this is one fairly complex dynamic system, and that header choice comes down to not only your particular combination, but the point in the rpm curve that you'd like to optimize power production. On any given combination, it's possible to design the headers to improve power down low, in the midrange, and even at high rpm.
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