Terms & Definitions
04-09-2011, 03:01 AM
#1
Terms & Definitions
Here is a list of common modifications for V6 Mustangs concerning basically how they function. This is by no means complete and I may add more in the future, but for now here's what I have:
Air Intake/Fuel
* Stock Air Intake – draws in air from the fender well to feed the engine. An air silencer is a cone shaped part that reduces whistling caused by incoming air. A paper air filter filters out dust and damaging particles in the air from entering and damaging the engine. Mass air meter measures the incoming air flow so that the proper fuel is supplied to the engine. Air box contains both the air filter and mass air meter. Air intake temperature sensor tells the ECU how hot or cold the incoming air is to further fine tune the fuel loads. Throttle body allows air to enter the intake plenum via way of a butterfly valve.
* Cold Air Intake - Frees up air flow by removing the paper air filter, air silencer, and, of course, the air box, to add both low and high end torque and power. Generally will add 2-4 rwhp, and 3-6 rwtq on an otherwise stock V6 Mustang.
Straight shot intakes are one of the oldest ways of making a CAI, it simply has the air filter lie inside the engine bay with a heat shield to protect the CAI from heat. Benefits include ease of changing/cleaning the filter, small hp gain. Drawbacks include heat soaking, which means that as engine temperature rises, the heat shield (if present) may not offer enough protection and the air intake will draw in some hot air which will limit performance gains.
Ram Air intakes use either a hood scoop, or air intake device that sits under the car. Both of these helps draw in addition air to the air filter to increase power, key is, the faster you go, the more air being drawn in, the better the hp gain. Benefits include great power gains, especially for F/I applications and racing. Drawbacks include price and difficulty with air filter changes/cleaning as the ram air system has to be partially uninstalled.
Cold Air Intake has the air filter sit inside the fender well to draw in cool dense air directly from it's source, there is no way for moister to enter the air intake on a Mustang with this setup. Benefits include decent power gains, and consistent access to cool air inside the fender well. Drawbacks include difficulty with changing the air filter.
High flow air filter with an air silencer delete. This method can be done several ways, but the most common way is to remove the air silencer from the air box, and drop in a high flow air filter to maximize air flow, this is a cheap, and efficient way to make a CAI as is adds nearly the same gains as an aftermarket CAI. Not many drawbacks aside from retaining the stock look, which can or can not be a bad thing depending on personal preference. Also, other drawbacks can include limited access to cooler air.
*High flow 75mm, 80mm, or 90mm Mas Air Meter (also refered to as a Mass Air Flow Sensor, the sensor actually sits ontop of the MAM) - This mod is required when your car exceeds stock MAF sensor abilities, a larger diameter throttle body has been added, or larger than stock fuel injectors have been added. A stock MAF can be made to run fuel injectors up to around 24 or 30lbs (depending on the tuner), by means of using a tuner to modify the fuel parameters of the ECU, however, after than point, an aftermarket MAF or major ECU tuning is needed. They function by sending false air flow data to the ECU to adjust for the high flow fuel injectors. It should be noted that most aftermarket MAFs run very rich so you will need some tuning to fine things out. Also, it is key that your MAF is set to both your ECU code, and fuel injector size, some also require throttle body size. A lack of info on any of the three could cause idle or performance issues as the MAF will be sending false/bad info to the ECU. Also, rule of thumb whatever size TB you have, your MAF needs to be the same size or larger. High flow MAFs will add next to nothing horse power wise on a stock to mildly modified sixer, but on boosted applications they can add approx .5 PSI (or 5 rwhp) when used with a power pipe.
* High Flow Larger Diameter Throttle Body - This mod will require porting of the upper intake to meet the new throttle body size, as your stock port opening on your intake will always approximately match your stock throttle body size. 94-98 Mustang V6s have a 50mm Throttle Body stock, and the only available upgrade is a 56mm throttle body made by BBK. 99-04 Mustang V6s have a 60mm throttle body, and can take both a 65mm throttle body, or a 70mm throttle body. 65mm Throttle bodies are for mildly modified mustangs with heads/cam/intake work, and or some type of forced induction. 70mm throttle bodies are for highly modified V6s running both a combination of F/I and H/C/I work. Power gains on a stock sixer will be minimal to around 2 rwhp, but on an F/I applications a larger TB can add around to .5 psi (or 5 rwhp).
* Fuel Injectors – fuel injectors plug into the fuel rails and lower intake and operate via an electronic signal that tells the injector when to spray. Fuel injectors come in many sizes (or fuel load via ft lbs) but the most common sizes are 14, 19, 24, 30, 42, 60, and 90lb injectors. The larger the number the more fuel the injector can supply to the engine. Larger injectors will not, under normal operating conditions, create more horse power or burn more gas as they will only supply the amount of fuel needed per the amount of air the engine requires. Fuel injectors simply support larger loads caused by higher flowering heads/intakes and or forced induction.
* Fuel Pressure Regulator – the fuel pressure regulator uses a vacuum line that taps into your intake manifold vacuum system to supply pressure to the fuel rails which in turn supplies pressure to the fuel injectors. Adjustable fuel pressure regulators allow the modification of fuel pressure to increase or decrease fuel pressure due to higher or lower loads caused by engine modifications.
* Fuel Rails – fuel rails connect to the fuel lines and supply fuel to the fuel injectors. Larger fuel rails allow for higher fuel loads required by modified engines.
Engine/Tuning
* Under Drive Pullies - Under drive pullies usually consist of a size reduced crank pulley, size increased water pump pulley, and size increased alternator pulley, to prevent cooling and charging problems. Under drive pullies come in both 24% size reduced cranks, and 42% size reduced cranks. Remember, the more reduction to the size of the crank pulley, the more power released, but the more strain your external accessories will take in the long run. NOTE!!! You will need a new belt specifically made for under drive pullies, as a stock belt will no longer work. Keep in mind under driving the external accessories is a proven way to free up power, however can put added strain on the electrical system especially if a higher powered stereo system is being supplied. Also, if you go supercharged, you may need either a stock pulley set up, or a pulley set up that comes with the S/C (like Vortech), as U/D pulleys will also under drive the S/C causing a lower boost (up to 7 PSI can come off your S/C due to U/D pullies).
* Tuners, Chips, and Tuning Software - There is a wide variety of tuners, chips, and software available, so do a little research to see what best fits your needs. Generally speaking, however these devices are used to increase power and performance by fine tuning the air/fuel ratio, increasing or decreasing timing depending on the engines needs, allowing the ECU to be reprogrammed for different rim or gear sizes, and many other parameters.
CHIPS are the oldest form of ECU modification. It's simple; you buy a chip with a pre-programmed tune, install it directly into your ecu, via a spare port Ford incorporated into the top of the ECU. Most new chips have multiple tunes programmed into them to allow for more than one type of driving condition and can be changed with a switch or dial switch. Downsides to chips are that they're pre-programmed, so any new changes that need to be made for new modifications can not be made and the chip must be uninstalled and reprogrammed.
Tuners are a little newer in that they are generally a hand held device that plugs into your OBD port and allows you to modify a handful of parameters on the ECU to boost performance. They can also hold several tunes at once, with the option to modify each one for newer needs. Downsides are that they're limited to what they can and can't modify, so more in depth tuning may be needed on large scale projects.
Tuning Software is one of the more recent additions into the racing world and is used just for that, racing. Tuning software is used in conjunction with a computer or handheld “piggy back unit” both of which plugs directly into the ECU and allows you to modify nearly every single parameter of your ECU to maximize engine efficiency, and performance. Downsides include massive learning curves, cost, and the need for a dyno and certain meters. Power gains will vary widely depending on your supporting modifications, as well as the route you choose, but generally speaking, tuners, chips, and software will net around 5-12 rwhp on a stock sixer with the average being around 8 rwhp.
* Intake Manifold/Plenum – The upper intake manifold, also called the plenum, is where the throttle body, egr, and main vacuum lines connect. The upper plenum also separates the incoming air into their individual ports on its way into the cylinders. The lower intake sits under the plenum and is what the fuel injectors and fuel rails attach. It’s the first spot where the fuel and air begins to mix before entering the heads.
* Heads – heads sit on top of the engine block and allow air to enter and leave the engine via valves opening and closing. Heads can be configured in 2V, 3V, and 4V setups. The more valves the more potential power. OHV (over head valve) engines such as the 3.8L, 5.0L, and 5.8L have two valves per cylinder (one for incoming air, one for out going) and the valves open and close via way of rockers that pushes the valves down. The rockers connect to the cam via push rods and the cam controls the valves opening/closing in this order. In SOHC (single over head cam) such as the 4.0L and early 4.6L modular engines the cam sits on top of the heads and directly controls the valves opening and closing. DOHC (dual over head cam) engines such as the newer 3.5L, 4.6L, 5.0L, and 5.4L engines have two cams with two sets of valves.
* Camshaft – the camshaft controls valve lift (how far the valve opens) and valve duration (how long that valve is open) to control air inflow/outflow. The cam can sit inside the block (OHV engines) or on top of the heads (SOHC and DOHC engines). Camshaft ratings are listed in lift in inches .480/.480 means the intake and exhaust valve opens .49 or roughly ½” and duration, the first number is intake, second is exhaust. Duration is simply how long that valve is open, or is expressed in the number of crankshaft degrees of engine rotation during which the valve is off the seat and is written as 220*/226* @ .050. Again first number is intake and second number is exhaust.
* Ported & Polished Intakes and Heads - There is a lot with this category so more information may need to be researched or asked on the forums to get a better understanding of what all takes place. First of all, porting is the widening of the ports to allow for more airflow. An example of this is when you widen the intake manifold throttle opening port to match the new size of a larger throttle body. Other forms of porting is port matching, which is when you match your port diameter to that of the gasket that mounts to it as gaskets are almost always larger in port size than the opening they go on. Polishing is just cleaning up the port, either from factory defects (factory ports are never perfectly due to mass production, so all that may be needed is a quick polish job to get rid of the extra aluminum or iron left over from the production process which has closed up the opening a little), polishing can also mean that your simply cleaning up the intake or head ports from grime build up and or the roughness left over from the porting process. This polishing smoothens up the port surface to reduce friction on the incoming air however recent studies have shown that polishing can actually reduce horse power because the air needs to tumble inside the intake, so it’s not done as often as it was in years past. Porting can be done at home using a porting kit, which is sold at nearly every auto parts store, but it's suggested that a pro do the job, especially heads. There are also several sites that sell pre ported kits, even though they do not support our site, a lot of sixers go there, and here is a quick breakdown of their kits. Remember to buy the kit that best suits your car, a too high flowing of a kit, is just as bad as too little air flow. The website is www.supersixmotorsports.com.
Exhaust
* Manifolds – connect to the heads and allow air to leave the engine. They do not evenly distribute air as it leaves the engine which can cause excessive back pressure which limits horse power. Manifolds are generally not coated with any coating so they have next to no protection from rust and do not hold in heat very well They are also not evenly round which further restricts airflow as they are the most simplistic form in modern cars of getting air out the engine and into the exhaust.
* Headers - Headers are similar to manifolds in that they connect to your heads and are the first line of your exhaust. Headers differ from manifolds in that they usually are designed to evenly distribute the air into the mid pipe and are generally larger and more rounded than manifolds. Stock V6s actually have headers and not exhaust manifolds, like most cars, so right out of the box they flow fairly well, and are good up to around 300hp. Headers come in many forms, types, and varieties. The first and oldest type of header is of course Steel.
Steel headers are just that, headers made of steel, they are cheap and easy to produce, however they are very prone to rusting out over time.
Chrome headers are steel headers coated in a couple of coats of chrome. Chrome headers not only add a nice bit of bling under the hood, but are also a little better insulating than steel as well as a little more rust resistant; one major downside is that they will discolor over time.
Ceramic coated headers steel headers coated in a layer of ceramic. They are the best insulating on the market, and one of the most rust resistant forms of headers out. Remember, the better the insulation, the more power you'll gain on catted systems, and the cooler and more efficient your engine runs due to the loss of heat transfer from the headers to the engine bay.
Shorty headers are just that, short, stock length headers, they run to just a few inches in behind the engine before they end and connect to the mid pipe. Aftermarket shorty headers are generally mandadril bent, which means, they don't have kinks where the bends are like some stock mass produced headers have.
Long tube headers are longer than shorty headers as they go further down towards the ground. This extended length gives the air more time to cool and stabilize before combining in the mid pipe which allows for more power and sound. Power gains will vary depending on the supporting mod of the car, but generally speaking a stock sixer with shorty headers will gain 1 rwhp, and that's iffy, and a stock sixer with long tubes can generally expect to see a 3-5 rwhp gain, remember these numbers are with no cat back exhaust work. Also, long tube headers require a shorter length mid pipe, so a standard mid pipe will no longer fit.
* Mid Pipe - the mid pipe is just that, the middle section of your exhaust, it lies between the headers and the cat back exhausts system. Mid pipes come in a variety of types, sizes and styles.
Stock midpipes are called a Y pipe in that a Y pipe looks like a Y in that it connects to the headers, then bends to form one single pipe. Stock pipe width is 2.25" in diameter.
H Pipes are just that, a mid pipe that looks like an H. Most aftermarket H pipes measure 2.5", so a shop would have to custom fab one to be 2.25" in diameter. H pipes offer much more sound than a y pipe will, and is one of the loudest midpipes on the market, however, in the upper RPMs, to have the extra sound a little tone and sound quality is lost.
X pipes, are like an H pipe, but in the shape of an X. They are milder sounding and have a tendency to pop when the RPMs are falling after reving up, but they keep much better sound tone and quality in the upper RPMs. These two types of pipes were made so that their could be even air transfer between the pipes due to the odd fire of a V8 engine, V6s gain no performance from either or, it's simply sound that changes.
Straight pipes are two parallel running pipes; there is no cross over in the middle. These are the loudest mid pipes, but also take the biggest hit to sound tone, and quality. Mid pipes can come with both cats, and no cats, having no cats is illegal in most states, and will not pass smog emissions, and is extremely hard to have installed as many shops will not install anything without cats. Only Mac and Pypes make mid pipes for V6s, but any shop can fab a pair for you. Power gains are debatable, but generally are around 1-3 rwhp.
* Catalytic Converters - Cats, as they are called, come in many forms, and quantities on a car. Mustang V6s have 4 cats, two are located just behind the headers, and the last two are located about 4-5 inches behind the first set. Cats are used to filter out the bad smells and gases caused from burning fuel in an engine. They function by slowing down the outgoing air, and allowing it to heat up, the air inside the cats has to reach a certain temperature before it can be let out, this heating up, along with a cats built in filters, are what allows them to remove a lot of the harmful gases in emissions waste. This is why great insulated headers can improve performance, and that's because the more heat not loss through the headers, the less time it takes the gases inside the cats to heat up and pass through. Removing the cats will add a deeper and louder tone to your car and will remove a lot of backpressure.
* MIL Eliminators - MIL Eliminators are used on systems that have had the cats removed. They plug into the O2 sensors, and then into the harness that at runs to your ECU. They function by sending false information to the ECU basically stating that the O2 sensors are on and functioning perfectly, in other words, they keep your check engine light from coming on.
* Cat Back Exhaust - Your cat back exhaust system is the last line of your exhaust, it is this part of the exhaust that includes the muffler and tailpipe.
Stock exhaust is just a single 2.25" exhaust.
Cat back V6 exhaust is a bolt on exhaust system that welds onto your stock y pipe. It is a form of dual exhaust, but isn't a true dual as there is about a 6" long piece of pipe that is a single pipe before the split occurs again. Cat back exhaust for sixers are generally higher pitched, and offer less sound quality than true duals, they also don't offer the added power as they barely free up any.
True duals are just that, two pipes running independent from each other from the mid pipe back. To get true duals on a sixer, either a shop has to do the work, or you can buy a kit for a GT. NOTE!!!! You must buy a V6 mid pipe, and a GT cat back exhaust!!! True duals are deeper in sound and offer better tone throughout the power band than the other two systems, aftermarket piping sizes are generally 2.5".
Drivetrain
* Open Differential - This is your stock rear end differential. V6s come with a 7.5" rear end, with an open differential. This means that the back right tire supplies most of the power, the left tire only supplies the overload from the right, and mainly the traction, and this is why most V6s suffer from one wheel bur-outs.
* Limited Slip Differential - A limited slip differential allows both wheels to supply the power to the ground while allowing a limited amount of slip to maintain traction and control. This allows for better traction upon launching and allows you to put more overall power to the ground safely, which is key on high powered N/A engines or engines running F/I.
* Gears - Your rear gears are what transfers your power from your drive train to your differential. 94-98 sixers come stock with 2.73 gears, 99-04s come with 3.27 gears. The number is a ratio or either 2.73/1 or 3.27/1, this means that your driveshaft will turn either 2.73 or 3.27 times to every tire rotation, increasing this ratio increases acceleration, but can have adverse effects on MPG, and top speed. Your gears also must match your rear end size. 7.5" V6 rear ends have several common aftermarket sizes, 3.45, 3.73, and 4.10.
Air Intake/Fuel
* Stock Air Intake – draws in air from the fender well to feed the engine. An air silencer is a cone shaped part that reduces whistling caused by incoming air. A paper air filter filters out dust and damaging particles in the air from entering and damaging the engine. Mass air meter measures the incoming air flow so that the proper fuel is supplied to the engine. Air box contains both the air filter and mass air meter. Air intake temperature sensor tells the ECU how hot or cold the incoming air is to further fine tune the fuel loads. Throttle body allows air to enter the intake plenum via way of a butterfly valve.
* Cold Air Intake - Frees up air flow by removing the paper air filter, air silencer, and, of course, the air box, to add both low and high end torque and power. Generally will add 2-4 rwhp, and 3-6 rwtq on an otherwise stock V6 Mustang.
Straight shot intakes are one of the oldest ways of making a CAI, it simply has the air filter lie inside the engine bay with a heat shield to protect the CAI from heat. Benefits include ease of changing/cleaning the filter, small hp gain. Drawbacks include heat soaking, which means that as engine temperature rises, the heat shield (if present) may not offer enough protection and the air intake will draw in some hot air which will limit performance gains.
Ram Air intakes use either a hood scoop, or air intake device that sits under the car. Both of these helps draw in addition air to the air filter to increase power, key is, the faster you go, the more air being drawn in, the better the hp gain. Benefits include great power gains, especially for F/I applications and racing. Drawbacks include price and difficulty with air filter changes/cleaning as the ram air system has to be partially uninstalled.
Cold Air Intake has the air filter sit inside the fender well to draw in cool dense air directly from it's source, there is no way for moister to enter the air intake on a Mustang with this setup. Benefits include decent power gains, and consistent access to cool air inside the fender well. Drawbacks include difficulty with changing the air filter.
High flow air filter with an air silencer delete. This method can be done several ways, but the most common way is to remove the air silencer from the air box, and drop in a high flow air filter to maximize air flow, this is a cheap, and efficient way to make a CAI as is adds nearly the same gains as an aftermarket CAI. Not many drawbacks aside from retaining the stock look, which can or can not be a bad thing depending on personal preference. Also, other drawbacks can include limited access to cooler air.
*High flow 75mm, 80mm, or 90mm Mas Air Meter (also refered to as a Mass Air Flow Sensor, the sensor actually sits ontop of the MAM) - This mod is required when your car exceeds stock MAF sensor abilities, a larger diameter throttle body has been added, or larger than stock fuel injectors have been added. A stock MAF can be made to run fuel injectors up to around 24 or 30lbs (depending on the tuner), by means of using a tuner to modify the fuel parameters of the ECU, however, after than point, an aftermarket MAF or major ECU tuning is needed. They function by sending false air flow data to the ECU to adjust for the high flow fuel injectors. It should be noted that most aftermarket MAFs run very rich so you will need some tuning to fine things out. Also, it is key that your MAF is set to both your ECU code, and fuel injector size, some also require throttle body size. A lack of info on any of the three could cause idle or performance issues as the MAF will be sending false/bad info to the ECU. Also, rule of thumb whatever size TB you have, your MAF needs to be the same size or larger. High flow MAFs will add next to nothing horse power wise on a stock to mildly modified sixer, but on boosted applications they can add approx .5 PSI (or 5 rwhp) when used with a power pipe.
* High Flow Larger Diameter Throttle Body - This mod will require porting of the upper intake to meet the new throttle body size, as your stock port opening on your intake will always approximately match your stock throttle body size. 94-98 Mustang V6s have a 50mm Throttle Body stock, and the only available upgrade is a 56mm throttle body made by BBK. 99-04 Mustang V6s have a 60mm throttle body, and can take both a 65mm throttle body, or a 70mm throttle body. 65mm Throttle bodies are for mildly modified mustangs with heads/cam/intake work, and or some type of forced induction. 70mm throttle bodies are for highly modified V6s running both a combination of F/I and H/C/I work. Power gains on a stock sixer will be minimal to around 2 rwhp, but on an F/I applications a larger TB can add around to .5 psi (or 5 rwhp).
* Fuel Injectors – fuel injectors plug into the fuel rails and lower intake and operate via an electronic signal that tells the injector when to spray. Fuel injectors come in many sizes (or fuel load via ft lbs) but the most common sizes are 14, 19, 24, 30, 42, 60, and 90lb injectors. The larger the number the more fuel the injector can supply to the engine. Larger injectors will not, under normal operating conditions, create more horse power or burn more gas as they will only supply the amount of fuel needed per the amount of air the engine requires. Fuel injectors simply support larger loads caused by higher flowering heads/intakes and or forced induction.
* Fuel Pressure Regulator – the fuel pressure regulator uses a vacuum line that taps into your intake manifold vacuum system to supply pressure to the fuel rails which in turn supplies pressure to the fuel injectors. Adjustable fuel pressure regulators allow the modification of fuel pressure to increase or decrease fuel pressure due to higher or lower loads caused by engine modifications.
* Fuel Rails – fuel rails connect to the fuel lines and supply fuel to the fuel injectors. Larger fuel rails allow for higher fuel loads required by modified engines.
Engine/Tuning
* Under Drive Pullies - Under drive pullies usually consist of a size reduced crank pulley, size increased water pump pulley, and size increased alternator pulley, to prevent cooling and charging problems. Under drive pullies come in both 24% size reduced cranks, and 42% size reduced cranks. Remember, the more reduction to the size of the crank pulley, the more power released, but the more strain your external accessories will take in the long run. NOTE!!! You will need a new belt specifically made for under drive pullies, as a stock belt will no longer work. Keep in mind under driving the external accessories is a proven way to free up power, however can put added strain on the electrical system especially if a higher powered stereo system is being supplied. Also, if you go supercharged, you may need either a stock pulley set up, or a pulley set up that comes with the S/C (like Vortech), as U/D pulleys will also under drive the S/C causing a lower boost (up to 7 PSI can come off your S/C due to U/D pullies).
* Tuners, Chips, and Tuning Software - There is a wide variety of tuners, chips, and software available, so do a little research to see what best fits your needs. Generally speaking, however these devices are used to increase power and performance by fine tuning the air/fuel ratio, increasing or decreasing timing depending on the engines needs, allowing the ECU to be reprogrammed for different rim or gear sizes, and many other parameters.
CHIPS are the oldest form of ECU modification. It's simple; you buy a chip with a pre-programmed tune, install it directly into your ecu, via a spare port Ford incorporated into the top of the ECU. Most new chips have multiple tunes programmed into them to allow for more than one type of driving condition and can be changed with a switch or dial switch. Downsides to chips are that they're pre-programmed, so any new changes that need to be made for new modifications can not be made and the chip must be uninstalled and reprogrammed.
Tuners are a little newer in that they are generally a hand held device that plugs into your OBD port and allows you to modify a handful of parameters on the ECU to boost performance. They can also hold several tunes at once, with the option to modify each one for newer needs. Downsides are that they're limited to what they can and can't modify, so more in depth tuning may be needed on large scale projects.
Tuning Software is one of the more recent additions into the racing world and is used just for that, racing. Tuning software is used in conjunction with a computer or handheld “piggy back unit” both of which plugs directly into the ECU and allows you to modify nearly every single parameter of your ECU to maximize engine efficiency, and performance. Downsides include massive learning curves, cost, and the need for a dyno and certain meters. Power gains will vary widely depending on your supporting modifications, as well as the route you choose, but generally speaking, tuners, chips, and software will net around 5-12 rwhp on a stock sixer with the average being around 8 rwhp.
* Intake Manifold/Plenum – The upper intake manifold, also called the plenum, is where the throttle body, egr, and main vacuum lines connect. The upper plenum also separates the incoming air into their individual ports on its way into the cylinders. The lower intake sits under the plenum and is what the fuel injectors and fuel rails attach. It’s the first spot where the fuel and air begins to mix before entering the heads.
* Heads – heads sit on top of the engine block and allow air to enter and leave the engine via valves opening and closing. Heads can be configured in 2V, 3V, and 4V setups. The more valves the more potential power. OHV (over head valve) engines such as the 3.8L, 5.0L, and 5.8L have two valves per cylinder (one for incoming air, one for out going) and the valves open and close via way of rockers that pushes the valves down. The rockers connect to the cam via push rods and the cam controls the valves opening/closing in this order. In SOHC (single over head cam) such as the 4.0L and early 4.6L modular engines the cam sits on top of the heads and directly controls the valves opening and closing. DOHC (dual over head cam) engines such as the newer 3.5L, 4.6L, 5.0L, and 5.4L engines have two cams with two sets of valves.
* Camshaft – the camshaft controls valve lift (how far the valve opens) and valve duration (how long that valve is open) to control air inflow/outflow. The cam can sit inside the block (OHV engines) or on top of the heads (SOHC and DOHC engines). Camshaft ratings are listed in lift in inches .480/.480 means the intake and exhaust valve opens .49 or roughly ½” and duration, the first number is intake, second is exhaust. Duration is simply how long that valve is open, or is expressed in the number of crankshaft degrees of engine rotation during which the valve is off the seat and is written as 220*/226* @ .050. Again first number is intake and second number is exhaust.
* Ported & Polished Intakes and Heads - There is a lot with this category so more information may need to be researched or asked on the forums to get a better understanding of what all takes place. First of all, porting is the widening of the ports to allow for more airflow. An example of this is when you widen the intake manifold throttle opening port to match the new size of a larger throttle body. Other forms of porting is port matching, which is when you match your port diameter to that of the gasket that mounts to it as gaskets are almost always larger in port size than the opening they go on. Polishing is just cleaning up the port, either from factory defects (factory ports are never perfectly due to mass production, so all that may be needed is a quick polish job to get rid of the extra aluminum or iron left over from the production process which has closed up the opening a little), polishing can also mean that your simply cleaning up the intake or head ports from grime build up and or the roughness left over from the porting process. This polishing smoothens up the port surface to reduce friction on the incoming air however recent studies have shown that polishing can actually reduce horse power because the air needs to tumble inside the intake, so it’s not done as often as it was in years past. Porting can be done at home using a porting kit, which is sold at nearly every auto parts store, but it's suggested that a pro do the job, especially heads. There are also several sites that sell pre ported kits, even though they do not support our site, a lot of sixers go there, and here is a quick breakdown of their kits. Remember to buy the kit that best suits your car, a too high flowing of a kit, is just as bad as too little air flow. The website is www.supersixmotorsports.com.
Exhaust
* Manifolds – connect to the heads and allow air to leave the engine. They do not evenly distribute air as it leaves the engine which can cause excessive back pressure which limits horse power. Manifolds are generally not coated with any coating so they have next to no protection from rust and do not hold in heat very well They are also not evenly round which further restricts airflow as they are the most simplistic form in modern cars of getting air out the engine and into the exhaust.
* Headers - Headers are similar to manifolds in that they connect to your heads and are the first line of your exhaust. Headers differ from manifolds in that they usually are designed to evenly distribute the air into the mid pipe and are generally larger and more rounded than manifolds. Stock V6s actually have headers and not exhaust manifolds, like most cars, so right out of the box they flow fairly well, and are good up to around 300hp. Headers come in many forms, types, and varieties. The first and oldest type of header is of course Steel.
Steel headers are just that, headers made of steel, they are cheap and easy to produce, however they are very prone to rusting out over time.
Chrome headers are steel headers coated in a couple of coats of chrome. Chrome headers not only add a nice bit of bling under the hood, but are also a little better insulating than steel as well as a little more rust resistant; one major downside is that they will discolor over time.
Ceramic coated headers steel headers coated in a layer of ceramic. They are the best insulating on the market, and one of the most rust resistant forms of headers out. Remember, the better the insulation, the more power you'll gain on catted systems, and the cooler and more efficient your engine runs due to the loss of heat transfer from the headers to the engine bay.
Shorty headers are just that, short, stock length headers, they run to just a few inches in behind the engine before they end and connect to the mid pipe. Aftermarket shorty headers are generally mandadril bent, which means, they don't have kinks where the bends are like some stock mass produced headers have.
Long tube headers are longer than shorty headers as they go further down towards the ground. This extended length gives the air more time to cool and stabilize before combining in the mid pipe which allows for more power and sound. Power gains will vary depending on the supporting mod of the car, but generally speaking a stock sixer with shorty headers will gain 1 rwhp, and that's iffy, and a stock sixer with long tubes can generally expect to see a 3-5 rwhp gain, remember these numbers are with no cat back exhaust work. Also, long tube headers require a shorter length mid pipe, so a standard mid pipe will no longer fit.
* Mid Pipe - the mid pipe is just that, the middle section of your exhaust, it lies between the headers and the cat back exhausts system. Mid pipes come in a variety of types, sizes and styles.
Stock midpipes are called a Y pipe in that a Y pipe looks like a Y in that it connects to the headers, then bends to form one single pipe. Stock pipe width is 2.25" in diameter.
H Pipes are just that, a mid pipe that looks like an H. Most aftermarket H pipes measure 2.5", so a shop would have to custom fab one to be 2.25" in diameter. H pipes offer much more sound than a y pipe will, and is one of the loudest midpipes on the market, however, in the upper RPMs, to have the extra sound a little tone and sound quality is lost.
X pipes, are like an H pipe, but in the shape of an X. They are milder sounding and have a tendency to pop when the RPMs are falling after reving up, but they keep much better sound tone and quality in the upper RPMs. These two types of pipes were made so that their could be even air transfer between the pipes due to the odd fire of a V8 engine, V6s gain no performance from either or, it's simply sound that changes.
Straight pipes are two parallel running pipes; there is no cross over in the middle. These are the loudest mid pipes, but also take the biggest hit to sound tone, and quality. Mid pipes can come with both cats, and no cats, having no cats is illegal in most states, and will not pass smog emissions, and is extremely hard to have installed as many shops will not install anything without cats. Only Mac and Pypes make mid pipes for V6s, but any shop can fab a pair for you. Power gains are debatable, but generally are around 1-3 rwhp.
* Catalytic Converters - Cats, as they are called, come in many forms, and quantities on a car. Mustang V6s have 4 cats, two are located just behind the headers, and the last two are located about 4-5 inches behind the first set. Cats are used to filter out the bad smells and gases caused from burning fuel in an engine. They function by slowing down the outgoing air, and allowing it to heat up, the air inside the cats has to reach a certain temperature before it can be let out, this heating up, along with a cats built in filters, are what allows them to remove a lot of the harmful gases in emissions waste. This is why great insulated headers can improve performance, and that's because the more heat not loss through the headers, the less time it takes the gases inside the cats to heat up and pass through. Removing the cats will add a deeper and louder tone to your car and will remove a lot of backpressure.
* MIL Eliminators - MIL Eliminators are used on systems that have had the cats removed. They plug into the O2 sensors, and then into the harness that at runs to your ECU. They function by sending false information to the ECU basically stating that the O2 sensors are on and functioning perfectly, in other words, they keep your check engine light from coming on.
* Cat Back Exhaust - Your cat back exhaust system is the last line of your exhaust, it is this part of the exhaust that includes the muffler and tailpipe.
Stock exhaust is just a single 2.25" exhaust.
Cat back V6 exhaust is a bolt on exhaust system that welds onto your stock y pipe. It is a form of dual exhaust, but isn't a true dual as there is about a 6" long piece of pipe that is a single pipe before the split occurs again. Cat back exhaust for sixers are generally higher pitched, and offer less sound quality than true duals, they also don't offer the added power as they barely free up any.
True duals are just that, two pipes running independent from each other from the mid pipe back. To get true duals on a sixer, either a shop has to do the work, or you can buy a kit for a GT. NOTE!!!! You must buy a V6 mid pipe, and a GT cat back exhaust!!! True duals are deeper in sound and offer better tone throughout the power band than the other two systems, aftermarket piping sizes are generally 2.5".
Drivetrain
* Open Differential - This is your stock rear end differential. V6s come with a 7.5" rear end, with an open differential. This means that the back right tire supplies most of the power, the left tire only supplies the overload from the right, and mainly the traction, and this is why most V6s suffer from one wheel bur-outs.
* Limited Slip Differential - A limited slip differential allows both wheels to supply the power to the ground while allowing a limited amount of slip to maintain traction and control. This allows for better traction upon launching and allows you to put more overall power to the ground safely, which is key on high powered N/A engines or engines running F/I.
* Gears - Your rear gears are what transfers your power from your drive train to your differential. 94-98 sixers come stock with 2.73 gears, 99-04s come with 3.27 gears. The number is a ratio or either 2.73/1 or 3.27/1, this means that your driveshaft will turn either 2.73 or 3.27 times to every tire rotation, increasing this ratio increases acceleration, but can have adverse effects on MPG, and top speed. Your gears also must match your rear end size. 7.5" V6 rear ends have several common aftermarket sizes, 3.45, 3.73, and 4.10.
Last edited by jthorn9; 04-09-2011 at 11:28 AM.
04-09-2011, 03:02 AM
#2
Forced Induction
* Forced induction means just that, forcing more air into the intake to produce more power, this can be accomplished in three ways; nitrous oxide, supercharging, turbo charging. Forced induction is simplified as “FI” where as naturally aspired motors (those running no boost) are written as “NA.”
* Nitrous Oxide (N2O) - Nitrous oxide works by spraying a mixture of N2O into the intake (or heads) to lower the air temperature of the incoming air, and add in more oxygen to increase power.
Dry - Dry N2O kits are the most common and most basic N2O kits. They function by spraying a dry (no fuel added), shot of N2O into the intake via a nozzle or intake plate. These kits require little tuning when running a 50 hp shot, or less, shot of N2O, however, larger shots should be tuned for safety. Advantages are little tuning, ease of install, modest power gains, ease of changing spray nozzles.
Wet - Wet N2O kits are also fairly common, however are a little more effective at making power than dry kits, they can also run larger shots (up to 300 hp). Wet kits function by mixing fuel and N2O together then spraying that stream into the intake. With that being said, all kits need to be tuned to prevent detonation, and engine damage. Advantages include more efficient power over a dry kit at the same shot, and more hp potential (more shot options). Downsides include cost, heavy tuning, more difficult install (although only marginally).
Direct Port - Direct port N2O kits are essentially wet kits that spray N2O directly into each individual port on the lower intake. This means that each cylinder gets the same amount of N2O/Air/Fuel ratio, which means much more power, and more power/ boost options, some people have ran 500+ direct port shots. So, advantages include more efficient power over regular wet kits, downsides include massive tuning, cost, and more difficult install.
* Supercharger - Supercharges add power by forcing more air into the intake to generate positive airflow (boost as opposed to the normal negative airflow vacuum), via a pulley driven gear assembly that either blows, or compresses air into the intake. The amount of air forced is measured in positive airflow (PSI) and is directly controlled by the size of the pulley driving the S/C unit. Superchargers vary in how much horse power they generate per PSI of boost due to the differences in the units, however 9-15 horse power per PSI is the generally accepted range of gain.
Roots - Roots superchargers are one of the oldest forms of superchargers. They function by having two tri star like rotors that spin in conjunction with one another to pull in and condense incoming air. These superchargers are great for making low end power, however do tend to fade out in the upper RPMs, and gears, they also suffer from heat soaking which means loss of power due to the heat of the S/C. This heat soaking can be reduced by using a by pass valve, or intercooler. Advantages, great low to mid end power, ease of install. Drawbacks, 55-70% supercharger efficiency per PSI (lower efficiency means less hp gain per PSI), heat soaking.
Twin Screw - Twin screws look and function nearly exactly like a roots S/C however with a core difference, instead of two tri star like screws, twin screw S/Cs use two screws that spin in conjunction with one another, this allows even more air to be compressed which makes much more power. Advantages, awesome low to mid power, 90-98% efficiency, instant boost at WOT at 2000 RPMs that holds throughout the power band giving it the low to mid end advantage over roots, centrifugal, turbos, and ease of install. Drawbacks, heat soaking is still a problem, unit still tends to lag out after 3rd gear or in extreme high RPMs.
Centrifugal - Centrifugal S/Cs mount to the side of the engine, and looks similar to a turbo, however is driven by the external accessories belt. Centrifugal S/Cs function by using an impeller to blow air into the air intake to create positive airflow. Centrifugal S/Cs do suffer a slight bit of S/C lag in the lower RPMs/Gears as it takes the S/C a short amount of time to fully spool up to blow air into the intake, however, once fully spooled they have a near perfect efficiency rating, and make loads of power, especially in the upper RPMs. Advantages, hp efficiency, no heat soaking, can be intercooled for even more hp and efficiency. Drawbacks, install more difficult, cost, if maintenance isn't maintained, impellers can fail and shoot directly into the intake, and possibly the engine (very rare).
* Turbo Charger - Turbos function by using taping into the headers (or header) to gain access to exhaust gases which are routed to the turbo unit via a down pipe and is used drive an impeller unit which blows air into the intake to create positive airflow. In short, turbos use the engines current power to make more power. They make the most power per PSI of the three, and are almost always used in racing applications due to their efficiency at making that power. However they do suffer from turbo lag and heat soaking, both of which can be reduced or nearly eliminated.
Single - Single turbo units mount off to the side of the engine, however unlike an S/C, are not tied into the external accessories. Instead, they generally tap into one header (some kits can use both), and reroute exiting air out the header to the turbo unit to drive the impeller, however an intercooler should be used to prevent heat soaking the turbo unit. Advantages, great middle to top end power, disadvantages, turbo lag (takes a short amount of time for the turbo to spool up) install time and difficulty, and cost.
Twin - Twin turbos function exactly like single units except use two turbo units and will tap into both headers for maximum efficiency. Twin turbos can generally be made to make more power than a single as two times the amount of air is being forced into the engine. Advantages, awesome middle to upper end power. Disadvantages, cost (very expensive), install difficulty (fairly involved and difficult install process), tuning (tuning must be done to effectively run these units and prevent detonation), cost, weight (generally heavier and more involved than single), and turbo lag.
Sequential - Sequential T/Cs are a rare form of twin turbos that uses two different kinds of turbos to maximize power both down low, and up high. One small turbo unit is used to make better boost at lower rpms/gears, a second larger turbo is used to make better boost in the middle/upper rpms/gears. In short, these turbos can make decent loads of power (although generally not as efficient as a good single or twin), and will provide that power throughout the entire power band. Advantages, decent power throughout the power band, minimal to no turbo lag. Disadvantages, cost (most expensive route), weight, install (install is also very involved), severe tuning (these units must be perfectly tuned in order to work in the appropriate manner, bad tuning can mean less efficiency, and potential engine damage).
* Forced induction means just that, forcing more air into the intake to produce more power, this can be accomplished in three ways; nitrous oxide, supercharging, turbo charging. Forced induction is simplified as “FI” where as naturally aspired motors (those running no boost) are written as “NA.”
* Nitrous Oxide (N2O) - Nitrous oxide works by spraying a mixture of N2O into the intake (or heads) to lower the air temperature of the incoming air, and add in more oxygen to increase power.
Dry - Dry N2O kits are the most common and most basic N2O kits. They function by spraying a dry (no fuel added), shot of N2O into the intake via a nozzle or intake plate. These kits require little tuning when running a 50 hp shot, or less, shot of N2O, however, larger shots should be tuned for safety. Advantages are little tuning, ease of install, modest power gains, ease of changing spray nozzles.
Wet - Wet N2O kits are also fairly common, however are a little more effective at making power than dry kits, they can also run larger shots (up to 300 hp). Wet kits function by mixing fuel and N2O together then spraying that stream into the intake. With that being said, all kits need to be tuned to prevent detonation, and engine damage. Advantages include more efficient power over a dry kit at the same shot, and more hp potential (more shot options). Downsides include cost, heavy tuning, more difficult install (although only marginally).
Direct Port - Direct port N2O kits are essentially wet kits that spray N2O directly into each individual port on the lower intake. This means that each cylinder gets the same amount of N2O/Air/Fuel ratio, which means much more power, and more power/ boost options, some people have ran 500+ direct port shots. So, advantages include more efficient power over regular wet kits, downsides include massive tuning, cost, and more difficult install.
* Supercharger - Supercharges add power by forcing more air into the intake to generate positive airflow (boost as opposed to the normal negative airflow vacuum), via a pulley driven gear assembly that either blows, or compresses air into the intake. The amount of air forced is measured in positive airflow (PSI) and is directly controlled by the size of the pulley driving the S/C unit. Superchargers vary in how much horse power they generate per PSI of boost due to the differences in the units, however 9-15 horse power per PSI is the generally accepted range of gain.
Roots - Roots superchargers are one of the oldest forms of superchargers. They function by having two tri star like rotors that spin in conjunction with one another to pull in and condense incoming air. These superchargers are great for making low end power, however do tend to fade out in the upper RPMs, and gears, they also suffer from heat soaking which means loss of power due to the heat of the S/C. This heat soaking can be reduced by using a by pass valve, or intercooler. Advantages, great low to mid end power, ease of install. Drawbacks, 55-70% supercharger efficiency per PSI (lower efficiency means less hp gain per PSI), heat soaking.
Twin Screw - Twin screws look and function nearly exactly like a roots S/C however with a core difference, instead of two tri star like screws, twin screw S/Cs use two screws that spin in conjunction with one another, this allows even more air to be compressed which makes much more power. Advantages, awesome low to mid power, 90-98% efficiency, instant boost at WOT at 2000 RPMs that holds throughout the power band giving it the low to mid end advantage over roots, centrifugal, turbos, and ease of install. Drawbacks, heat soaking is still a problem, unit still tends to lag out after 3rd gear or in extreme high RPMs.
Centrifugal - Centrifugal S/Cs mount to the side of the engine, and looks similar to a turbo, however is driven by the external accessories belt. Centrifugal S/Cs function by using an impeller to blow air into the air intake to create positive airflow. Centrifugal S/Cs do suffer a slight bit of S/C lag in the lower RPMs/Gears as it takes the S/C a short amount of time to fully spool up to blow air into the intake, however, once fully spooled they have a near perfect efficiency rating, and make loads of power, especially in the upper RPMs. Advantages, hp efficiency, no heat soaking, can be intercooled for even more hp and efficiency. Drawbacks, install more difficult, cost, if maintenance isn't maintained, impellers can fail and shoot directly into the intake, and possibly the engine (very rare).
* Turbo Charger - Turbos function by using taping into the headers (or header) to gain access to exhaust gases which are routed to the turbo unit via a down pipe and is used drive an impeller unit which blows air into the intake to create positive airflow. In short, turbos use the engines current power to make more power. They make the most power per PSI of the three, and are almost always used in racing applications due to their efficiency at making that power. However they do suffer from turbo lag and heat soaking, both of which can be reduced or nearly eliminated.
Single - Single turbo units mount off to the side of the engine, however unlike an S/C, are not tied into the external accessories. Instead, they generally tap into one header (some kits can use both), and reroute exiting air out the header to the turbo unit to drive the impeller, however an intercooler should be used to prevent heat soaking the turbo unit. Advantages, great middle to top end power, disadvantages, turbo lag (takes a short amount of time for the turbo to spool up) install time and difficulty, and cost.
Twin - Twin turbos function exactly like single units except use two turbo units and will tap into both headers for maximum efficiency. Twin turbos can generally be made to make more power than a single as two times the amount of air is being forced into the engine. Advantages, awesome middle to upper end power. Disadvantages, cost (very expensive), install difficulty (fairly involved and difficult install process), tuning (tuning must be done to effectively run these units and prevent detonation), cost, weight (generally heavier and more involved than single), and turbo lag.
Sequential - Sequential T/Cs are a rare form of twin turbos that uses two different kinds of turbos to maximize power both down low, and up high. One small turbo unit is used to make better boost at lower rpms/gears, a second larger turbo is used to make better boost in the middle/upper rpms/gears. In short, these turbos can make decent loads of power (although generally not as efficient as a good single or twin), and will provide that power throughout the entire power band. Advantages, decent power throughout the power band, minimal to no turbo lag. Disadvantages, cost (most expensive route), weight, install (install is also very involved), severe tuning (these units must be perfectly tuned in order to work in the appropriate manner, bad tuning can mean less efficiency, and potential engine damage).
04-09-2011, 09:58 AM
#5
04-09-2011, 08:06 PM
#10
Actually I started it a while back when I was unemployed and couldn't sleep at night, so I just got bored and started writing it. I forgot all about it and when I was browsing through my hard drive I saw it, proff read it and decided to post it up.