The New RX8 Owner FAQ -- 1-25-09
01-05-2009 | 12:12 AM
#1
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
The New RX8 Owner FAQ -- 1-25-09
Purpose:
The purpose of this FAQ thread is to give anyone a good "RX8/cars for Dummies" overview of available modifications, proper maintance, and the fun they can have with the RX8.
This page will be updated regularly for a while. Please check the date on the thread to know the latest version.
If you have any contributions or notice any errors please contact me via PM so I can modify this thread.
Common Issues (Technical Service Bulletins) TSBs - http://www.finishlineperformance.com....php?pageid=11 (Milky foam on dipstick, oil in intake, lack of power, etc...)
Things Every RX8 owner should know:
1. First and most importantly, this car drinks oil. Part of this engine's normal operation is that it injects oil via the Oil Metering Pump (little thing with clear straws by the water pump pulley) into the engine in order to lubricate the engine seals. Why does it do this? Because the size and the shape of the combustion chamber inside the rotary engine is so large that an oiling system from a piston engine is not effective. Oil consumption can range from 1 Liter / 1000 Miles to 1 Liter / 3000 Miles depending on your car and how you drive it, generally redlining the engine will cause more oil consumption, a day at the track could have you drinking 1-2 quarts in a day. It is a bad idea to let your oil get low. This is bad because in this engine, oil is also used as a cooling mechanism for this car. Oil is run through the center of the crankshaft and to two oil coolers on the front of the car that act as radiators. When you let your oil get low you concentrate the heat in a smaller volume of oil, making cooling less effective. Also you concentrate large particulates and sludge inside your engine which may then be injected into the combustion chamber. Keep your engine as close to the fill level as possible.
2. The rotary engine is easier to flood than a normal engine. This is because the shape of the combustion chamber inside the rotary engine, it is much larger than that of a piston engine and requires more fuel to start it up. When shut off prematurely this fuel stays in the engine and makes it difficult for the spark plugs to light off the mixture. If you start up the engine try and get it up to operating temp before shutting it off. If this is not possible due to time constraints rev. the engine to 5K rpms and hold it there for 8-10 seconds then shut it off. Any higher than this for extended periods can overheat and ruin your catalytic converter.
3. The rotary engine is much more sensitive to temperature changes than a piston engine. The precise shape of the operating movement of the rotors inside the housings requires that all dimensions be exact for optimum function. When the engine is heating up the metals used in the engine are expanding (due to heat) to their correct operating dimensions. During this time it is best to keep the engine below 4000 rpms to allow all the metals in the engine to slowly heat up at the same time. After the engine has reached operating temperature the redline is the limit!
4. The stock tires are high performance variety. They normally last between 6000-27000 miles per set. You can buy lower performance tires that can last much longer than this.
5. The brakes are of the high performance variety. They normally last between 12000-30000 miles per set for the fronts and maybe twice that long for the rear set. You can buy lower performance brakes that last much longer than this.
6. The body panels (hood, doors, roof) of the RX8 are aluminum, they are nearly impossible to cheaply repair if dented. No that bodyshop guy isn't trying to cheat you, Expensive car = expensive repairs.
7. 87 octane is fine for some cars, contrary to the owner's manual. On other cars it produces a noticeable lack of power. Try it and find out.
8. A lot of the maintenance such as changing the spark plugs, coils, and wires, are easier than you think! If you have some free time try it yourself and save some major cash.
9. If you start up the engine and it sounds like a lawnmower ate a rock, your engine is blown.
The purpose of this FAQ thread is to give anyone a good "RX8/cars for Dummies" overview of available modifications, proper maintance, and the fun they can have with the RX8.
This page will be updated regularly for a while. Please check the date on the thread to know the latest version.
If you have any contributions or notice any errors please contact me via PM so I can modify this thread.
Common Issues (Technical Service Bulletins) TSBs - http://www.finishlineperformance.com....php?pageid=11 (Milky foam on dipstick, oil in intake, lack of power, etc...)
Things Every RX8 owner should know:
1. First and most importantly, this car drinks oil. Part of this engine's normal operation is that it injects oil via the Oil Metering Pump (little thing with clear straws by the water pump pulley) into the engine in order to lubricate the engine seals. Why does it do this? Because the size and the shape of the combustion chamber inside the rotary engine is so large that an oiling system from a piston engine is not effective. Oil consumption can range from 1 Liter / 1000 Miles to 1 Liter / 3000 Miles depending on your car and how you drive it, generally redlining the engine will cause more oil consumption, a day at the track could have you drinking 1-2 quarts in a day. It is a bad idea to let your oil get low. This is bad because in this engine, oil is also used as a cooling mechanism for this car. Oil is run through the center of the crankshaft and to two oil coolers on the front of the car that act as radiators. When you let your oil get low you concentrate the heat in a smaller volume of oil, making cooling less effective. Also you concentrate large particulates and sludge inside your engine which may then be injected into the combustion chamber. Keep your engine as close to the fill level as possible.
2. The rotary engine is easier to flood than a normal engine. This is because the shape of the combustion chamber inside the rotary engine, it is much larger than that of a piston engine and requires more fuel to start it up. When shut off prematurely this fuel stays in the engine and makes it difficult for the spark plugs to light off the mixture. If you start up the engine try and get it up to operating temp before shutting it off. If this is not possible due to time constraints rev. the engine to 5K rpms and hold it there for 8-10 seconds then shut it off. Any higher than this for extended periods can overheat and ruin your catalytic converter.
3. The rotary engine is much more sensitive to temperature changes than a piston engine. The precise shape of the operating movement of the rotors inside the housings requires that all dimensions be exact for optimum function. When the engine is heating up the metals used in the engine are expanding (due to heat) to their correct operating dimensions. During this time it is best to keep the engine below 4000 rpms to allow all the metals in the engine to slowly heat up at the same time. After the engine has reached operating temperature the redline is the limit!
4. The stock tires are high performance variety. They normally last between 6000-27000 miles per set. You can buy lower performance tires that can last much longer than this.
5. The brakes are of the high performance variety. They normally last between 12000-30000 miles per set for the fronts and maybe twice that long for the rear set. You can buy lower performance brakes that last much longer than this.
6. The body panels (hood, doors, roof) of the RX8 are aluminum, they are nearly impossible to cheaply repair if dented. No that bodyshop guy isn't trying to cheat you, Expensive car = expensive repairs.
7. 87 octane is fine for some cars, contrary to the owner's manual. On other cars it produces a noticeable lack of power. Try it and find out.
8. A lot of the maintenance such as changing the spark plugs, coils, and wires, are easier than you think! If you have some free time try it yourself and save some major cash.
9. If you start up the engine and it sounds like a lawnmower ate a rock, your engine is blown.
Last edited by staticlag; 02-02-2010 at 10:52 AM.
01-05-2009 | 12:46 AM
#2
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Intakes:
The addition of an aftermarket intake is one of the simplest and most common performance modifications for any vehicle.
Concept:
By reducing the resistance of the factory intake you can allow air to move more easily into the combustion chamber, thereby increasing engine power.
How does this apply to the RX8?:
Need to Know VFAD = Variable Fresh Air Duct, a foot long sock and funnel behind the front bumper.
The stock intake on the RX8 is a very good one. It has been analyzed by every reputable company since 2004 to enhance its performance. To date the most gains that one can expect with an aftermarket intake are around 5-8 HP.
The most common style of aftermarket intake for the RX8 is the “Short Ram” style made popular by the K&N version 1. This design is comprised primarily of removing the entire stock intake filter box and its connecting VFAD and replacing it with a K&N filter on a short tube. The main drawback of this design is that it introduced a lot of turbulence into the sensitive engine air metering module known as the Mass Air Flow (MAF) sensor. Another huge drawback to this design was that it only sucked in hot air from the engine compartment. Rotaries run very hot and the K&N version one was situated behind the A/C heat exchanger, and the radiator. This caused for very unstable idling and a loss of around 10 hp in general.
Since this first K&N version 1 was released. Many other companies have picked up on the RX8 sensitivity to a "Short Ram" style. Other companies have designed ducts or tubes that try and mimic the path of the stock VFAD. K&N released a version 2 that isolated the filter from the engine compartment and changed it shape to promote lower intake temperatures and less turbulence for the sensitive engine electronics.
Most RX8 owners are happy buying an intake only for its exotic sound.
Tech Info:
The stock intake is comprised of 3 main parts. In order from the engine to the atmosphere. (Accordion Tube, Filter Box, VFAD Assembly).
The accordion tube is located directly in front of the throttle body. Its main purpose is to provide flexibility to allow the engine to move independently from the filter box which is bolted to the frame.
The filter box is made of two sections. The next section which is connected to the accordion tube has a sensor screwed into the top of it. This is the MAF sensor. Then before this are two mesh screens which serve to eliminate any air turbulence allowing the MAF sensor to correctly determine the amount of incoming air. The filter goes on next and then we come to section #2 which is bolted to the frame of the car.
The final piece of the stock intake is the VFAD assembly. The Variable Fresh Air Duct (VFAD) was designed by Mazda engineers to overcome the limitations of common factory intakes. The main limitation of factory intakes being that either one can make them work well for low RPM usage or for high RPM usage but not both. The VFAD overcomes this limitation by allowing the engine computer to shorten the path and direction of incoming air when the engine is over 5500 RPMs.
Pictures and Links:
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/intake-intakes-intakes-90202/
Concept:
By reducing the resistance of the factory intake you can allow air to move more easily into the combustion chamber, thereby increasing engine power.
How does this apply to the RX8?:
Need to Know VFAD = Variable Fresh Air Duct, a foot long sock and funnel behind the front bumper.
The stock intake on the RX8 is a very good one. It has been analyzed by every reputable company since 2004 to enhance its performance. To date the most gains that one can expect with an aftermarket intake are around 5-8 HP.
The most common style of aftermarket intake for the RX8 is the “Short Ram” style made popular by the K&N version 1. This design is comprised primarily of removing the entire stock intake filter box and its connecting VFAD and replacing it with a K&N filter on a short tube. The main drawback of this design is that it introduced a lot of turbulence into the sensitive engine air metering module known as the Mass Air Flow (MAF) sensor. Another huge drawback to this design was that it only sucked in hot air from the engine compartment. Rotaries run very hot and the K&N version one was situated behind the A/C heat exchanger, and the radiator. This caused for very unstable idling and a loss of around 10 hp in general.
Since this first K&N version 1 was released. Many other companies have picked up on the RX8 sensitivity to a "Short Ram" style. Other companies have designed ducts or tubes that try and mimic the path of the stock VFAD. K&N released a version 2 that isolated the filter from the engine compartment and changed it shape to promote lower intake temperatures and less turbulence for the sensitive engine electronics.
Most RX8 owners are happy buying an intake only for its exotic sound.
Tech Info:
The stock intake is comprised of 3 main parts. In order from the engine to the atmosphere. (Accordion Tube, Filter Box, VFAD Assembly).
The accordion tube is located directly in front of the throttle body. Its main purpose is to provide flexibility to allow the engine to move independently from the filter box which is bolted to the frame.
The filter box is made of two sections. The next section which is connected to the accordion tube has a sensor screwed into the top of it. This is the MAF sensor. Then before this are two mesh screens which serve to eliminate any air turbulence allowing the MAF sensor to correctly determine the amount of incoming air. The filter goes on next and then we come to section #2 which is bolted to the frame of the car.
The final piece of the stock intake is the VFAD assembly. The Variable Fresh Air Duct (VFAD) was designed by Mazda engineers to overcome the limitations of common factory intakes. The main limitation of factory intakes being that either one can make them work well for low RPM usage or for high RPM usage but not both. The VFAD overcomes this limitation by allowing the engine computer to shorten the path and direction of incoming air when the engine is over 5500 RPMs.
Pictures and Links:
https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/intake-intakes-intakes-90202/
Last edited by staticlag; 01-26-2009 at 08:40 PM.
01-05-2009 | 12:50 AM
#3
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Exhausts:
The addition of an aftermarket exhaust is an easy modification that allows for some weight savings and some slight power gains.
Concept:
As with the intake, reducing the resistance that exhaust gas requires to exit the engine improves the performance. The exhaust piping is long and heavy, by purchasing an aftermarket exhaust you are most likely lightening up the system allowing for weight savings as well. There is a delicate balance between sound suppression and performance, usually buyers are forced to pick either a quiet exhaust system with minimal/no gains, or a noisy exhaust system with gains of 5-10 hp.
How does this apply to the RX8?:
Need to know:
There are 4 pieces to the rx8 system. In order from the engine to the atmosphere they are: Headers, Catalytic Converter, Mid-Pipe, Muffler
-- Some people remove the catalytic converter and replace it with another "Mid-Pipe." It is called a mid-pipe because it is between the headers and the muffler! Another common name for this specific pipe that can replace the catalytic converter is called a "Test-Pipe" or "Straight-Pipe"
The stock exhaust on the RX8 is a very good one. By default the rx8's exhaust was made to be as quiet as possible. This has made it on the bulky side but not entirely unlivable. Most rx8 exhaust systems focus on increasing the stock piping diameter from 2.5 inches to 3 inches and reducing the muffler size, and/or modifying the catalytic converter. All improvements are mitigated by the fact that the stock headers have a 2.5 inch exit port, this reduces the gains from a 3" exhaust. While headers are available for the rx8 this is an expensive modification that not many choose at this time.
The RX8 can never sound like a V8 engine, just as a V8 can never sound like a rotary. If you want a deep sound then the Racing Beat exhaust is your best bet!
Tech Info:
Headers: The Stock Rx8 headers are a "Log" style header. All three exhaust ports from the engine dump into one tube. Yes, the rx8 has two rotors in its engine but it outputs 3 exhaust ports, the front and rear are dedicated to the front and rear rotors respectively, but the center port is a split combination of the rotors. The stock headers are well heat-shielded, this makes them heavy. All header kits at this time are shipped without heat shielding. A common modification to these headers before installation is the addition of ceramic heat coating to provide heat shieldng. Most header kits are of an "equal length design" where all three port runners are the same length then combined at one collection point. Many think that the center combined rx8 port removes any benefit of this equal length design. Gain is approx 5-6 hp.
Catalytic Converter: The Stock Catalytic Converter, or CAT for short, is a shielded double design. It has a front element that does most of the NOx scrubbing, then it has the factory emissions narrowband O2 sensor, then it has the second element to scrub any additional NOx. This design is for EPA purposes whereby if the first element fails the car still has another element to keep it emissions legal. Removal or modification of the catalytic converter for a street driven vehicle is illegal in the United States, if you are caught hefty fines and towing are likely. To improve emissions the car injects oxygen from the outside air into the exhaust system on startup. This causes additional heat in the catalytic converter to warm it up to optimal operating temperature. Heat increases the speed of the reaction in the cat, it must warm up to be able to effectively convert the exhaust gasses the car is putting out.
Most aftermarket companies focus on replacing the catalytic element with expensive lightweight high performance elements, removing the heat shielding, or removing the cat all-together. total gains for complete removal of the cat are around 7-10hp.
Midpipe: Just a pipe connecting the catalytic converter to the muffler!
Muffler: This is commonly called a "cat-back" to denote that it is behind the catalytic converter! The stock muffler is a large single canister design. Most companies focus on changing this large single canister design to a split dual lightweight canister design and making the exhaust system tips attractive with chrome. Most rx8 owners are happy with buying an aftermarket muffler (catback) for its sounds and looks. Total gain from any muffler is around 5-8 Hp.
Final Info: The numbers may look attractive if you add them up. But the gains do not stack. If you put the best headers with no emissions equipment, and no muffler you would only gain 7-15 hp the higher numbers (10-15hp) are dependent on aftermarket modification of the rx8's engine computer to utilize these changes.
Pictures and Links:
https://www.rx8club.com/showthread.p...14#post1406114
Concept:
As with the intake, reducing the resistance that exhaust gas requires to exit the engine improves the performance. The exhaust piping is long and heavy, by purchasing an aftermarket exhaust you are most likely lightening up the system allowing for weight savings as well. There is a delicate balance between sound suppression and performance, usually buyers are forced to pick either a quiet exhaust system with minimal/no gains, or a noisy exhaust system with gains of 5-10 hp.
How does this apply to the RX8?:
Need to know:
There are 4 pieces to the rx8 system. In order from the engine to the atmosphere they are: Headers, Catalytic Converter, Mid-Pipe, Muffler
-- Some people remove the catalytic converter and replace it with another "Mid-Pipe." It is called a mid-pipe because it is between the headers and the muffler! Another common name for this specific pipe that can replace the catalytic converter is called a "Test-Pipe" or "Straight-Pipe"
The stock exhaust on the RX8 is a very good one. By default the rx8's exhaust was made to be as quiet as possible. This has made it on the bulky side but not entirely unlivable. Most rx8 exhaust systems focus on increasing the stock piping diameter from 2.5 inches to 3 inches and reducing the muffler size, and/or modifying the catalytic converter. All improvements are mitigated by the fact that the stock headers have a 2.5 inch exit port, this reduces the gains from a 3" exhaust. While headers are available for the rx8 this is an expensive modification that not many choose at this time.
The RX8 can never sound like a V8 engine, just as a V8 can never sound like a rotary. If you want a deep sound then the Racing Beat exhaust is your best bet!
Tech Info:
Headers: The Stock Rx8 headers are a "Log" style header. All three exhaust ports from the engine dump into one tube. Yes, the rx8 has two rotors in its engine but it outputs 3 exhaust ports, the front and rear are dedicated to the front and rear rotors respectively, but the center port is a split combination of the rotors. The stock headers are well heat-shielded, this makes them heavy. All header kits at this time are shipped without heat shielding. A common modification to these headers before installation is the addition of ceramic heat coating to provide heat shieldng. Most header kits are of an "equal length design" where all three port runners are the same length then combined at one collection point. Many think that the center combined rx8 port removes any benefit of this equal length design. Gain is approx 5-6 hp.
Catalytic Converter: The Stock Catalytic Converter, or CAT for short, is a shielded double design. It has a front element that does most of the NOx scrubbing, then it has the factory emissions narrowband O2 sensor, then it has the second element to scrub any additional NOx. This design is for EPA purposes whereby if the first element fails the car still has another element to keep it emissions legal. Removal or modification of the catalytic converter for a street driven vehicle is illegal in the United States, if you are caught hefty fines and towing are likely. To improve emissions the car injects oxygen from the outside air into the exhaust system on startup. This causes additional heat in the catalytic converter to warm it up to optimal operating temperature. Heat increases the speed of the reaction in the cat, it must warm up to be able to effectively convert the exhaust gasses the car is putting out.
Most aftermarket companies focus on replacing the catalytic element with expensive lightweight high performance elements, removing the heat shielding, or removing the cat all-together. total gains for complete removal of the cat are around 7-10hp.
Midpipe: Just a pipe connecting the catalytic converter to the muffler!
Muffler: This is commonly called a "cat-back" to denote that it is behind the catalytic converter! The stock muffler is a large single canister design. Most companies focus on changing this large single canister design to a split dual lightweight canister design and making the exhaust system tips attractive with chrome. Most rx8 owners are happy with buying an aftermarket muffler (catback) for its sounds and looks. Total gain from any muffler is around 5-8 Hp.
Final Info: The numbers may look attractive if you add them up. But the gains do not stack. If you put the best headers with no emissions equipment, and no muffler you would only gain 7-15 hp the higher numbers (10-15hp) are dependent on aftermarket modification of the rx8's engine computer to utilize these changes.
Pictures and Links:
https://www.rx8club.com/showthread.p...14#post1406114
Last edited by staticlag; 01-20-2009 at 02:38 PM.
01-05-2009 | 12:51 AM
#4
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Wheels:
Changing the factory wheels to aftermarket wheels is a very simple to install modification which can drastically increase the performance of the vehicle. This is one of the easiest ways to obtain marked gains with any vehicle. Conversely by adding heavier more fancy looking wheels there is a significant decrease in performance.
Concept:
By adding lightweight wheels you are reducing the weight of the largest rotating part of the drivetrain. Heavy objects have a lot of inertia, inertia is defined by Newton's second law of motion, that objects in motion like to stay in motion and objects at rest like to stay at rest. Heavy objects have more inertia than lighter objects because they have more mass. By reducing the weight of the wheels you are reducing the power that the engine wastes overcoming the wheels' inertia.
How does this apply to the RX8?:
The stock wheels were manufactured at two different facilities they can weigh between 20-22 lbs.
The stock bolt pattern is 5x114.3. Wheels are 18" by 8" wide. Wider wheels can fit wider tires on them allowing for added traction.
A very popular racing wheel is the lightweight Enkei RPF-1 which is 18" by 9.5" wide and a lightweight 18lbs a wheel.
Each brand of wheel has different clearances and different "offsets." Knowing if a particular wheel will fit your car is dependent on the size of your wheel wells, and brake kit. There is no exact way to know if a wheel will fit if the person has no experience with the car or the wheels. Buyer beware when buying from inexperienced salespeople.
Care must be taken when selecting wheels, usually cheaper wheels are manufactured with inferior processes which makes them very prone to denting on road imperfections.
Some people buy wheels solely for looks and not performance. Typically upsizing a wheel (18" to 19", 20", etc) to a fancier variety adds a lot of mass. That gain in mass results in significantly lower performance.
Staggered wheels (making the rears wider than the front) may look cool, but the added traction on one part of the car has a massive negative effect on the handling of this car. Since our weight balance and steering is fairly neutral going staggered is a bad idea.
Tech Info:
Quoted from TireRack.com(http://www.tirerack.com/wheels/tech/...p?techid=101):
Quote from TireRack.com(http://www.tirerack.com/wheels/tech/...rentpage=101):
Pictures and Links:
http://www.tirerack.com/wheels/tech/index.jsp
http://www.tirerack.com/wheels/tech/....jsp?techid=90
http://www.tirerack.com/wheels/tech/...currentpage=90
Concept:
By adding lightweight wheels you are reducing the weight of the largest rotating part of the drivetrain. Heavy objects have a lot of inertia, inertia is defined by Newton's second law of motion, that objects in motion like to stay in motion and objects at rest like to stay at rest. Heavy objects have more inertia than lighter objects because they have more mass. By reducing the weight of the wheels you are reducing the power that the engine wastes overcoming the wheels' inertia.
How does this apply to the RX8?:
The stock wheels were manufactured at two different facilities they can weigh between 20-22 lbs.
The stock bolt pattern is 5x114.3. Wheels are 18" by 8" wide. Wider wheels can fit wider tires on them allowing for added traction.
A very popular racing wheel is the lightweight Enkei RPF-1 which is 18" by 9.5" wide and a lightweight 18lbs a wheel.
Each brand of wheel has different clearances and different "offsets." Knowing if a particular wheel will fit your car is dependent on the size of your wheel wells, and brake kit. There is no exact way to know if a wheel will fit if the person has no experience with the car or the wheels. Buyer beware when buying from inexperienced salespeople.
Care must be taken when selecting wheels, usually cheaper wheels are manufactured with inferior processes which makes them very prone to denting on road imperfections.
Some people buy wheels solely for looks and not performance. Typically upsizing a wheel (18" to 19", 20", etc) to a fancier variety adds a lot of mass. That gain in mass results in significantly lower performance.
Staggered wheels (making the rears wider than the front) may look cool, but the added traction on one part of the car has a massive negative effect on the handling of this car. Since our weight balance and steering is fairly neutral going staggered is a bad idea.
Tech Info:
Quoted from TireRack.com(http://www.tirerack.com/wheels/tech/...p?techid=101):
"The offset of a wheel is the distance from its hub mounting surface to the centerline of the wheel. The offset can be one of three types (measured in millimeters).*
Zero Offset
The hub mounting surface is even with the centerline of the wheel.
Positive
The hub mounting surface is toward the front or wheel side of the wheel. Positive offset wheels are generally found on front wheel drive cars and newer rear drive cars.
Negative
The hub mounting surface is toward the back or brake side of the wheels centerline. "Deep dish" wheels are typically a negative offset.
If the offset of the wheel is not correct for the car, the handling can be adversely affected. When the width of the wheel changes, the offset also changes numerically. If the offset were to stay the same while you added width, the additional width would be split evenly between the inside and outside. For most cars, this won't work correctly. "
Zero Offset
The hub mounting surface is even with the centerline of the wheel.
Positive
The hub mounting surface is toward the front or wheel side of the wheel. Positive offset wheels are generally found on front wheel drive cars and newer rear drive cars.
Negative
The hub mounting surface is toward the back or brake side of the wheels centerline. "Deep dish" wheels are typically a negative offset.
If the offset of the wheel is not correct for the car, the handling can be adversely affected. When the width of the wheel changes, the offset also changes numerically. If the offset were to stay the same while you added width, the additional width would be split evenly between the inside and outside. For most cars, this won't work correctly. "
"Wheel Construction
There are many factors to consider when purchasing an alloy wheel.
One-Piece Cast Wheels
This is the most common type of aluminum wheel. The casting of wheels is the process of getting molten aluminum inside a mold to form a wheel. There are different ways this can be accomplished and although it sounds simple, this is truly an art when done properly.
GRAVITY CASTING
Gravity casting is the most basic process of pouring molten aluminum into a mold utilizing the earth's gravity to fill the mold. Gravity casting offers a very reasonable production cost and is a good method for casting designs that are more visually oriented or when reducing weight is not a primary concern. Since the process relies on gravity to fill the mold, the aluminum is not as densely packed in the mold as some other casting processes. Often gravity cast wheels will have a higher weight to achieve the required strength.
LOW PRESSURE CASTING
Low pressure casting uses positive pressure to move the molten aluminum into the mold quicker and achieve a finished product that has improved mechanical properties (more dense) over a gravity cast wheel. Low-pressure casting has a slightly higher production cost over gravity casting. Low pressure is the most common process approved for aluminum wheels sold to the O.E.M. market. Low-pressure cast wheels offer a good value for the aftermarket as well. Some companies offer wheels that are produced under a higher pressure in special casting equipment to create a wheel that is lighter and stronger than a wheel produced in low pressure. Once again in the quest for lighter weight, there is a higher cost associated with the process.
SPUN-RIM, FLOW-FORMING OR RIM ROLLING TECHNOLOGY
This specialized process begins with a low pressure type of casting and uses a special machine that spins the initial casting, heats the outer portion of the casting and then uses steel rollers pressed against the rim area to pull the rim to its final width and shape. The combination of the heat, pressure and spinning create a rim area with the strength similar to a forged wheel without the high cost of the forging. Some of the special wheels produced for the O.E.M. high performance or limited production vehicles utilize this type of technology resulting in a light and strong wheel at a reasonable cost. BBS has used this technology for several years in their production of racing wheels for Formula One and Indy cars. BBS's RC wheel for the aftermarket is an example of a wheel produced using spun rim technology.
FORGED OR SEMI-SOLID FORGED
CNC Mill
In forged wheels, computer numerically controlled
(CNC) mills add the cosmetics and the bolt circle to exacting tolerances.
The ultimate in one-piece wheels. Forging is the process of forcing a solid billet of aluminum between the forging dies under an extreme amount of pressure. This creates a finished product that is very dense, very strong and therefore can be very light. The costs of tooling, development, equipment, etc., make this type of wheel very exclusive and usually demand a high price in the aftermarket. Semi-solid forging (SSF) is a process that heats a billet of special alloy to an almost liquid state and then the aluminum is forced into a mold at a very high rate. The finished product offers mechanical properties very similar to a forged wheel without the high production and tooling costs of a forged wheel. When low weight and performance are on your priority list, the SSF technology offers an excellent value. Currently only SSR (Speed Star Racing) from Japan is licensed to use this process for the production of wheels. Read more about semi-solid forging technology.
Multi-Piece Wheels
This type of wheel utilizes two or three components assembled together to produce a finished wheel. Multi-piece wheels can use many different methods of manufacturing. Centers can be cast in various methods or forged. The rim sections for 3-piece wheels are normally spun from disks of aluminum. Generally, spun rim sections offer the ability to custom-tailor wheels for special applications that would not be available otherwise. The rim sections are bolted to the center and normally a sealant is applied in or on the assembly area to seal the wheel. This type of 3-piece construction was originally developed for racing in the early 1970s and has been used on cars ever since. The 3-piece wheels are most popular in the 17" and larger diameters.
There are now many options for 2-piece wheels in the market. The 2-piece wheel design does not offer as wide a range of application that a 3-piece wheel allows, however they are more common in the market and the prices start well below the average 3-piece wheel. Some 2-piece wheels have the center bolted into a cast or cast/spun rim section and other manufacturers press centers into spun rim sections and weld the unit together. When BBS developed a new 2-piece wheel to replace the previous 3-piece street wheel, they used the special rim-rolling technology (originally developed for racing wheels) to give the rim section the weight and strength advantages similar to a forged rim. On the high-end of the 2-piece wheel market you can find wheels using forged rims and forged centers. Since these are only sold in small volume and due to the high development and production costs associated with the forging process, they tend to be on the high end of the price scale."
There are many factors to consider when purchasing an alloy wheel.
One-Piece Cast Wheels
This is the most common type of aluminum wheel. The casting of wheels is the process of getting molten aluminum inside a mold to form a wheel. There are different ways this can be accomplished and although it sounds simple, this is truly an art when done properly.
GRAVITY CASTING
Gravity casting is the most basic process of pouring molten aluminum into a mold utilizing the earth's gravity to fill the mold. Gravity casting offers a very reasonable production cost and is a good method for casting designs that are more visually oriented or when reducing weight is not a primary concern. Since the process relies on gravity to fill the mold, the aluminum is not as densely packed in the mold as some other casting processes. Often gravity cast wheels will have a higher weight to achieve the required strength.
LOW PRESSURE CASTING
Low pressure casting uses positive pressure to move the molten aluminum into the mold quicker and achieve a finished product that has improved mechanical properties (more dense) over a gravity cast wheel. Low-pressure casting has a slightly higher production cost over gravity casting. Low pressure is the most common process approved for aluminum wheels sold to the O.E.M. market. Low-pressure cast wheels offer a good value for the aftermarket as well. Some companies offer wheels that are produced under a higher pressure in special casting equipment to create a wheel that is lighter and stronger than a wheel produced in low pressure. Once again in the quest for lighter weight, there is a higher cost associated with the process.
SPUN-RIM, FLOW-FORMING OR RIM ROLLING TECHNOLOGY
This specialized process begins with a low pressure type of casting and uses a special machine that spins the initial casting, heats the outer portion of the casting and then uses steel rollers pressed against the rim area to pull the rim to its final width and shape. The combination of the heat, pressure and spinning create a rim area with the strength similar to a forged wheel without the high cost of the forging. Some of the special wheels produced for the O.E.M. high performance or limited production vehicles utilize this type of technology resulting in a light and strong wheel at a reasonable cost. BBS has used this technology for several years in their production of racing wheels for Formula One and Indy cars. BBS's RC wheel for the aftermarket is an example of a wheel produced using spun rim technology.
FORGED OR SEMI-SOLID FORGED
CNC Mill
In forged wheels, computer numerically controlled
(CNC) mills add the cosmetics and the bolt circle to exacting tolerances.
The ultimate in one-piece wheels. Forging is the process of forcing a solid billet of aluminum between the forging dies under an extreme amount of pressure. This creates a finished product that is very dense, very strong and therefore can be very light. The costs of tooling, development, equipment, etc., make this type of wheel very exclusive and usually demand a high price in the aftermarket. Semi-solid forging (SSF) is a process that heats a billet of special alloy to an almost liquid state and then the aluminum is forced into a mold at a very high rate. The finished product offers mechanical properties very similar to a forged wheel without the high production and tooling costs of a forged wheel. When low weight and performance are on your priority list, the SSF technology offers an excellent value. Currently only SSR (Speed Star Racing) from Japan is licensed to use this process for the production of wheels. Read more about semi-solid forging technology.
Multi-Piece Wheels
This type of wheel utilizes two or three components assembled together to produce a finished wheel. Multi-piece wheels can use many different methods of manufacturing. Centers can be cast in various methods or forged. The rim sections for 3-piece wheels are normally spun from disks of aluminum. Generally, spun rim sections offer the ability to custom-tailor wheels for special applications that would not be available otherwise. The rim sections are bolted to the center and normally a sealant is applied in or on the assembly area to seal the wheel. This type of 3-piece construction was originally developed for racing in the early 1970s and has been used on cars ever since. The 3-piece wheels are most popular in the 17" and larger diameters.
There are now many options for 2-piece wheels in the market. The 2-piece wheel design does not offer as wide a range of application that a 3-piece wheel allows, however they are more common in the market and the prices start well below the average 3-piece wheel. Some 2-piece wheels have the center bolted into a cast or cast/spun rim section and other manufacturers press centers into spun rim sections and weld the unit together. When BBS developed a new 2-piece wheel to replace the previous 3-piece street wheel, they used the special rim-rolling technology (originally developed for racing wheels) to give the rim section the weight and strength advantages similar to a forged rim. On the high-end of the 2-piece wheel market you can find wheels using forged rims and forged centers. Since these are only sold in small volume and due to the high development and production costs associated with the forging process, they tend to be on the high end of the price scale."
http://www.tirerack.com/wheels/tech/index.jsp
http://www.tirerack.com/wheels/tech/....jsp?techid=90
http://www.tirerack.com/wheels/tech/...currentpage=90
Last edited by staticlag; 01-07-2009 at 11:05 AM.
01-05-2009 | 12:51 AM
#5
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Pulleys:
The pullies people usually refer to are the crankshaft pulley, the water pump pulley and the alternator pulley; all three of these are connected by one belt. The A/C compressor runs off another pulley and belt from the crank. Changing the pullies allows you to change the amount of engine power given to the alternator, the water pump, or the A/C compressor.
Concept:
By reducing the "parasitic loss" or drain from car accessories such as water pump, alternator, A/C, you can allow the engine to put more of its power towards forward movement. This is a trade-off however, by reducing the power given to these accessories you can have A/C problems, charging problems, or insufficient coolant flow at low RPMs (mainly idle).
How does this apply to the RX8?:
Your engine has to run a bunch of accessory items to keep it in good running order. These accessory items are usually the water pump to move coolant though the system, the alternator which provides spark to the spark plugs and charge to the rest of your electrical system, and your Air Conditioner compressor which cools the air inside the cabin. The RX8's pulley system is very refined and lightweight. On other cars, mainly domestics, the pulley system can be around 20lbs total. As with wheels the amount of mass the pulley itself has means that energy is wasted in making it turn. On most other cars significant gains can be achieved though installing a lightweight pulley system which trades the factory steel pullies for aluminum ones. The RX8's pulley system is around 4 lbs for all pullies involved. No gains can be achieved by switching to a lightweight system alone.
There is another way to receive gains from aftermarket pullies. This is by "Underdriving" them. The term underdriving comes from the fact that you are supplying less power to the pulley than is usual. The only way this can be achieved is by changing the diameter of the pullies involved. For instance, if 1 turn of the engine turns the alternator 4 times, then an underdriven alternator would be set to turn 3 or fewer times based on one complete turn of the crankshaft.
By making the crank pulley smaller you underdrive all the accessories.
By making the accessory pullies bigger you underdrive all the accessories.
Tech Info:
The RX8 crank pulley is comprised of two pieces can be removed with basic hand tools. The water pump pulley can be removed with basic hand tools. The alternator pulley requires an impact wrench to remove. Most serious racers remove the A/C compressor entirely since its function is purely for comfort.
Typical Gains from the Agency Power pulley set are between 5-7hp
The stock water pump cavitates (hits the water so hard it causes bubbles) at high RPMs. This causes overheating when used at high RPMs for extended periods (at the track). A switch to an underdrive system that slows down the water pump is a worthwhile investment, though by slowing it down it also may make coolant flow at idle insufficient.
Pictures and Links:
DIY by staticlag https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/agency-power-underdrive-pulley-review-pics-90310/
Concept:
By reducing the "parasitic loss" or drain from car accessories such as water pump, alternator, A/C, you can allow the engine to put more of its power towards forward movement. This is a trade-off however, by reducing the power given to these accessories you can have A/C problems, charging problems, or insufficient coolant flow at low RPMs (mainly idle).
How does this apply to the RX8?:
Your engine has to run a bunch of accessory items to keep it in good running order. These accessory items are usually the water pump to move coolant though the system, the alternator which provides spark to the spark plugs and charge to the rest of your electrical system, and your Air Conditioner compressor which cools the air inside the cabin. The RX8's pulley system is very refined and lightweight. On other cars, mainly domestics, the pulley system can be around 20lbs total. As with wheels the amount of mass the pulley itself has means that energy is wasted in making it turn. On most other cars significant gains can be achieved though installing a lightweight pulley system which trades the factory steel pullies for aluminum ones. The RX8's pulley system is around 4 lbs for all pullies involved. No gains can be achieved by switching to a lightweight system alone.
There is another way to receive gains from aftermarket pullies. This is by "Underdriving" them. The term underdriving comes from the fact that you are supplying less power to the pulley than is usual. The only way this can be achieved is by changing the diameter of the pullies involved. For instance, if 1 turn of the engine turns the alternator 4 times, then an underdriven alternator would be set to turn 3 or fewer times based on one complete turn of the crankshaft.
By making the crank pulley smaller you underdrive all the accessories.
By making the accessory pullies bigger you underdrive all the accessories.
Tech Info:
The RX8 crank pulley is comprised of two pieces can be removed with basic hand tools. The water pump pulley can be removed with basic hand tools. The alternator pulley requires an impact wrench to remove. Most serious racers remove the A/C compressor entirely since its function is purely for comfort.
Typical Gains from the Agency Power pulley set are between 5-7hp
The stock water pump cavitates (hits the water so hard it causes bubbles) at high RPMs. This causes overheating when used at high RPMs for extended periods (at the track). A switch to an underdrive system that slows down the water pump is a worthwhile investment, though by slowing it down it also may make coolant flow at idle insufficient.
Pictures and Links:
DIY by staticlag https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/agency-power-underdrive-pulley-review-pics-90310/
Last edited by staticlag; 01-05-2009 at 11:35 AM.
01-05-2009 | 12:52 AM
#6
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Short Shifter:
A short shifter is a shifter replacement for a manual transmission car that can lower the shifter height, shorten the movement required to change gears, or both.
Concept:
By shortening the height and the distance required to shift gears installing a short shifter can make changing gears faster and more precise.
How does this apply to the RX8?:
The RX8's transmission is directly below the shifter, this means that the stock shifter is already very "short." Being that close to the transmission the driver can get the downside of hearing the gears, or feeling more vibration in the shift lever.
If one is willing to install one of the available short shifter upgrades for the rx8 they can enjoy even shorter and more precise shifting at the expense of shifting the car being a bit more difficult physically.
The short shifter is arguably the most enjoyable and greatest value of all the rx8 modifications to date. Rarely do you hear of a problem with the short shifter or someone who doesn't think its a night and day difference between the stock version.
Tech Info:
The shifting rod of a manual transmission car relies on a lever arm and fulcrum to translate your hand's movements into shift lever movements inside the transmission. By moving the fulcrum point higher toward your hand, you require less movement to produce greater movements on the other side of the fulcrum inside the transmission. The downside is that you need to be stronger to shift the gears since you have less of a lever advantage by shortening the arm.
Pictures and Links:
Axialflow Short Shifter https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/rp-short-shifter-installed-first-impressions-51489/
http://www.axialflow.com/
Concept:
By shortening the height and the distance required to shift gears installing a short shifter can make changing gears faster and more precise.
How does this apply to the RX8?:
The RX8's transmission is directly below the shifter, this means that the stock shifter is already very "short." Being that close to the transmission the driver can get the downside of hearing the gears, or feeling more vibration in the shift lever.
If one is willing to install one of the available short shifter upgrades for the rx8 they can enjoy even shorter and more precise shifting at the expense of shifting the car being a bit more difficult physically.
The short shifter is arguably the most enjoyable and greatest value of all the rx8 modifications to date. Rarely do you hear of a problem with the short shifter or someone who doesn't think its a night and day difference between the stock version.
Tech Info:
The shifting rod of a manual transmission car relies on a lever arm and fulcrum to translate your hand's movements into shift lever movements inside the transmission. By moving the fulcrum point higher toward your hand, you require less movement to produce greater movements on the other side of the fulcrum inside the transmission. The downside is that you need to be stronger to shift the gears since you have less of a lever advantage by shortening the arm.
Pictures and Links:
Axialflow Short Shifter https://www.rx8club.com/series-i-aftermarket-performance-modifications-23/rp-short-shifter-installed-first-impressions-51489/
http://www.axialflow.com/
Last edited by staticlag; 01-05-2009 at 04:44 PM.
01-05-2009 | 12:53 AM
#7
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Nitrous Oxide:
Nitrous Oxide is a oxygen source used to temporarily increase the power of an engine. Nitrous Oxide is a colorless gas that is normally sold in liquid form in auto performance shops. The type of Nitrous sold in these shops contains trace amounts of a chemical called sulfur dioxide. Sulfur Dioxide is very poisonous to humans (Corrosive. Toxic - high concentrations are fatal. Typical exposure limit 2 ppm (8 hr TWA), 5 ppm (10 min TWA).) A small amount can give brain damage and larger amounts can kill you. Never inhale automotive grade nitrous oxide for any reason.
Concept
For a fire to burn you (basically) need three things. 1) Fuel 2) Oxygen 3) Heat. These three things only work in a static proportion to one another. Example: for every ounce of fuel you need 14 oz of air, and maybe 10000 Volts to ignite it. To increase power you need to increase all three of them equally.
Normally, the only relatively static quantity in the equation is the Oxygen content of air. Fuel systems have a lot of overhead and the same goes for ignition systems, the only difficult thing to adjust is the amount of oxygen entering the engine. A person could put as much fuel or spark as they want in the combustion chamber but without Oxygen the reaction will not occur (the same is true of the other two as well). Both Nitrous oxide and a forced induction system try and increase the oxygen content in the combustion chamber so that fuel and the resulting power can be increased as well.
How does this apply to the RX8?
The best system known to work with the RX8 is a wet type system sprayed either from a tap in the accordion hose or from an aftermarket throttle spacer plate.
Tech Info
Need to Know:
Stoichiometric - the ratio in a reaction where all of the reactants are fully consumed in making the products. (no leftovers)
The Mass Air-Flow sensor can determine oxygen quantity with either an oxygen senor or a temperature sensor. Since all air on planet earth has more or less the same amount of oxygen in it, but oxygen quantity can change based on the humidity or temperature, the MAF sensor senses the temperature, gets info from the car's onboard barometer, and looks up the oxygen present in the air and the correct amount of fuel and spark to add from its onboard memory.
Nitrous nozzles are commonly sold in the following format: xxx HP shot, this is because in most cases a 50 HP shot nozzle will net you 50 hp on the car. This is done because it is easier than listing the vales like this: 0.0032 inch nozzle.
There are three systems of Nitrous Oxide that are commonly used in any application.
"Dry" Nitrous:
In a dry nitrous oxide system nitrous is sprayed before the Mass Air-Flow (MAF) sensor, when the nitrous changes from liquid form to the gaseous form it takes energy from the air around it, basically it "cools the air" as its sprayed. This cool air charge tells the MAF to inject more fuel into the engine(because it thinks that there is colder more dense air entering the engine[which is the case]). There is no fuel control in this system, which makes it very easy to install but risky for any but the smallest and safest power levels.
"Wet" Nitrous:
Nitrous and extra fuel are injected together after the MAF sensor. The user needs to calculate the correct size of nozzles used in spraying both the nitrous and the fuel in order to maintain the correct stoichiometric ratio. This setup is more difficult to install because you need to tap into the fuel system which can be dangerous due to high pressures (50-80psi) used in modern cars. The downside to this setup is that at a certain point the fuel and the nitrous do not correctly mix with the air going into the engine, you have some ports getting too much fuel and others getting too much nitrous or not enough. This makes very high power levels dangerous with this setup.
"Direct-Port" Nitrous:
In a direct port system you either use a spacer plate that injects nitrous from the fuel injector location or a specially modified intake runner as the place for the nozzles. Each cylinder/rotor gets its separate nitrous and fuel nozzle system. The very direct & precise spray makes sure that there is an even distribution of fuel and nitrous in each chamber, making higher power levels possible. The downside is that this system is more difficult to install than the other two.
Pictures and Links:
Charles R. Hill, our resident nitrous guru has done it all. https://www.rx8club.com/series-i-major-horsepower-upgrades-93/rules-nitrous-use-109820/
Concept
For a fire to burn you (basically) need three things. 1) Fuel 2) Oxygen 3) Heat. These three things only work in a static proportion to one another. Example: for every ounce of fuel you need 14 oz of air, and maybe 10000 Volts to ignite it. To increase power you need to increase all three of them equally.
Normally, the only relatively static quantity in the equation is the Oxygen content of air. Fuel systems have a lot of overhead and the same goes for ignition systems, the only difficult thing to adjust is the amount of oxygen entering the engine. A person could put as much fuel or spark as they want in the combustion chamber but without Oxygen the reaction will not occur (the same is true of the other two as well). Both Nitrous oxide and a forced induction system try and increase the oxygen content in the combustion chamber so that fuel and the resulting power can be increased as well.
How does this apply to the RX8?
The best system known to work with the RX8 is a wet type system sprayed either from a tap in the accordion hose or from an aftermarket throttle spacer plate.
Tech Info
Need to Know:
Stoichiometric - the ratio in a reaction where all of the reactants are fully consumed in making the products. (no leftovers)
The Mass Air-Flow sensor can determine oxygen quantity with either an oxygen senor or a temperature sensor. Since all air on planet earth has more or less the same amount of oxygen in it, but oxygen quantity can change based on the humidity or temperature, the MAF sensor senses the temperature, gets info from the car's onboard barometer, and looks up the oxygen present in the air and the correct amount of fuel and spark to add from its onboard memory.
Nitrous nozzles are commonly sold in the following format: xxx HP shot, this is because in most cases a 50 HP shot nozzle will net you 50 hp on the car. This is done because it is easier than listing the vales like this: 0.0032 inch nozzle.
There are three systems of Nitrous Oxide that are commonly used in any application.
"Dry" Nitrous:
In a dry nitrous oxide system nitrous is sprayed before the Mass Air-Flow (MAF) sensor, when the nitrous changes from liquid form to the gaseous form it takes energy from the air around it, basically it "cools the air" as its sprayed. This cool air charge tells the MAF to inject more fuel into the engine(because it thinks that there is colder more dense air entering the engine[which is the case]). There is no fuel control in this system, which makes it very easy to install but risky for any but the smallest and safest power levels.
"Wet" Nitrous:
Nitrous and extra fuel are injected together after the MAF sensor. The user needs to calculate the correct size of nozzles used in spraying both the nitrous and the fuel in order to maintain the correct stoichiometric ratio. This setup is more difficult to install because you need to tap into the fuel system which can be dangerous due to high pressures (50-80psi) used in modern cars. The downside to this setup is that at a certain point the fuel and the nitrous do not correctly mix with the air going into the engine, you have some ports getting too much fuel and others getting too much nitrous or not enough. This makes very high power levels dangerous with this setup.
"Direct-Port" Nitrous:
In a direct port system you either use a spacer plate that injects nitrous from the fuel injector location or a specially modified intake runner as the place for the nozzles. Each cylinder/rotor gets its separate nitrous and fuel nozzle system. The very direct & precise spray makes sure that there is an even distribution of fuel and nitrous in each chamber, making higher power levels possible. The downside is that this system is more difficult to install than the other two.
Pictures and Links:
Charles R. Hill, our resident nitrous guru has done it all. https://www.rx8club.com/series-i-major-horsepower-upgrades-93/rules-nitrous-use-109820/
Last edited by staticlag; 01-26-2009 at 12:18 AM.
01-05-2009 | 12:54 AM
#9
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Fuel Pump:
Last edited by staticlag; 01-26-2009 at 08:33 PM.
01-05-2009 | 12:55 AM
#10
Thread Starter
The Professor
Joined: Aug 2004
Posts: 3,479
Likes: 6
From: Omaha, NE
Spark Plugs:
A spark plug is the name for the device that is used to ignite the fuel and air mixture in the engine.
Concept
An electrical current generated by the car's alternator is changed in voltage (from 12V to several thousand) by the car's coils and passed by conducting wire to the plug where it sparks across a small gap of free air generating several thousand degrees of heat inside the electrical arc and igniting the combustible fuel mixture in the engine.
How does this apply to the RX8?
Many common cars employ a spark plug with a copper center electrode and a steel ground electrode. The RX8 employs a stock spark plug with an Iridium center electrode and an platinum ground electrode. Platinum and Iridium are used in high performance vehicles because they are much harder and more durable than copper. Since the metals used for the conductors are more heat & shock resistant manufacturers are able to change the shape of the electrodes into smaller more efficient designs without fear of melting.
Tech Info
There are several different shapes of spark plug electrodes; there are also different threading designs that can serve to transfer heat more effectively away from the plug and into the housing.
The stock RX8 sparkplug is of the "fine-wire" design where the shape of the electrodes are made as small as possible. This is done to allow the flame propagation from the fuel ignition to proceed unhindered from the spark site. Normal sparkplugs have a hefty ground electrode...
In progress......
Pictures and Links:
Concept
An electrical current generated by the car's alternator is changed in voltage (from 12V to several thousand) by the car's coils and passed by conducting wire to the plug where it sparks across a small gap of free air generating several thousand degrees of heat inside the electrical arc and igniting the combustible fuel mixture in the engine.
How does this apply to the RX8?
Many common cars employ a spark plug with a copper center electrode and a steel ground electrode. The RX8 employs a stock spark plug with an Iridium center electrode and an platinum ground electrode. Platinum and Iridium are used in high performance vehicles because they are much harder and more durable than copper. Since the metals used for the conductors are more heat & shock resistant manufacturers are able to change the shape of the electrodes into smaller more efficient designs without fear of melting.
Tech Info
There are several different shapes of spark plug electrodes; there are also different threading designs that can serve to transfer heat more effectively away from the plug and into the housing.
The stock RX8 sparkplug is of the "fine-wire" design where the shape of the electrodes are made as small as possible. This is done to allow the flame propagation from the fuel ignition to proceed unhindered from the spark site. Normal sparkplugs have a hefty ground electrode...
In progress......
Pictures and Links:
Last edited by staticlag; 01-26-2009 at 08:38 PM.