Suspension Tuning 101
12-05-2002
#1
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 
Suspension Tuning 101
Suspension Tuning 101
This Thread was started in response to the lack of knowledge and understanding of suspension and Performance Handling. Feel free to post any questions, disagreements or additions.
How to make your car handle well. Sounds easy, right? Just throw on some springs, upsized tires and Poof!!! Your car is now a screaming mountain eating demon. Well, not really. There is a lot more to Performance Handling then just buying aftermarket parts and slapping them on your car. So what can we do to improve oppon our little 7th. gen civic’s handling? The answer is, Lots! With just a little $ and proper tuning, you can make your civic do things a Mustang Cobra couldn’t even think of doing. Sure, you may not be able to beat a Cobra in the ¼ mile, but get him on a mountain road, and he’ll eat a tree long before you even come close to one. So back to the matter at hand. How do we make our cars the fastest on the mountain? The answer to that is a bit simpler then you think.
Part 1. Intro to Vehicle Dynamics
To get the maximum performance out of your car you have to first under stand Vehicle dynamics. Basically Vehicle dynamics are all of the things that affect the way your car handles, such as accelerating, braking, turning and various road surfaces and conditions. Most of this deals with weight transfer. When you accelerate, weight is transferred to the back, when you brake, weight goes to the front. And when you turn weight is transferred to the outside of the corner. The rest deals with your suspensions ability to keep the tires firmly planted on the ground and keeping the tire contact patch as large as possible.
1. Weight
So how does weight transfer affect the handling of your car? Weight directly affects tire traction. The more weight on a tire the more traction it will produce, to a point. (The ratio of weight to traction increase is not liner it’s more of a parabola, where the amount of traction gained with more weight decreases as more weight is applied. I.e. A tire with 100 lb placed on it will make 100 lb of traction, where a tire with 1000 lb will make 670 lb of traction). This is why a lighter car is inherently more maneuverable then a heavy car. The heavier car may produce more “total” traction, but the lighter car will make Proportionally more traction to its weight. That is our first advantage over the heaver V8s. Now you know how weigh affects traction, now we can apply that to handling.
When you accelerate, weight is transferred to the back tires, increasing their traction while the front tires lose traction, this loss of traction on the drive wheels is why FWD cars don’t do very well as dragsters. (It also makes a 10 sec FWD car all that more impressive). On a RWD car that natural weight transfer is a great bonus, by placing more weight on the drive wheels. When you are braking, weight gets transferred to the front, that’s why your front brakes are more important then your rears. The front tires gain traction and the rears lose traction. Finally when you turn, weight is transferred to the out side of the corner. This causes the outside tires to gain traction and the insides to lose traction. Now this action may seen ok, your gaining traction in one place and losing traction in an other, so the total traction should remain the same right? Well, No. But because the amount of traction gained/lost is not a liner function, the inner tires will lose traction quicker then the outer tires gain traction meaning, the total traction gained by placing more weight on the outside is less then the traction lost by the inside tires, equaling less total traction than if no weight transfer had occurred. Another problem with corner weight transfer is that the weigh does not get distributed equally front and rear. In our FWD cars more of the weight is placed on the front then the back. This is predominantly why our cars understeer.
So we can conclude that Weight transfer is bad for cornering. So how do we get rid of weight transfer? You can’t, even cars with no suspension such as Go Karts have to deal with weight transfer. You can however control where the weight is transferred, when it’s transferred and how fast it gets there.
Finally when dealing with weight there is Sprung and Unsprung weight, there is a big difference on how theses 2 types of weight affect handeling. Sprung weight are the parts of an automobile that are supported by the front and rear springs. They suspend the vehicle's frame, body, engine, and the power train above the wheels. Unsprung weight includes wheels and tires, brake assemblies, the rear axle assembly (If your car is RWD), and other structural members not supported by the springs. For handeling you want a low unsprung weight. The reason behind this is basic physics, F=ma. Force = Mass x Acceleration. If you’re wheels, tires etc. are heavy then it takes much more effort for your springs to keep the tires on the ground, if the unsprung weight is great enough the tire may leave the ground when it contacts a bump. And for you ¼ mile buffs, One pound of "unsprung" weight is equal to 8 pounds of "sprung" weight. For every 10 pounds of unsprung weight removed you may pick up as much as .01 seconds in quarter mile ET. So lighten those wheels, For track I wouldn't go bigger then a light weight 17 (Currently I run 17's on the street and Compititon 15's on the track,I autocross), on the strip, probably a light 14'.
2. Traction
Ok you now know how weight affects traction, but what exactly is “traction”. Traction is the tires ability to grip the road, and a tire only has so much traction. Tires make traction though friction between the rubber molecules at the tire contact patch and the road surface. And as discussed before, traction increases as vertical load on the tire increases, which is why aerodynamic downforce works so well. Lastly, a tire will make more traction if the entire contact patch is equally loaded. There are 5 characteristics that affect traction. 1. Basic tire design and construction. 2. Sidewall rigidity. 3. Tread rubber compound. 4. Tread design. And 5. Tire size. Of these characteristics we only have a choice of Tire size, compound and Tread design. We can also control the tires pressure, camber, toe in/out and camber change (Camber Change is the number of degrees of camber that wheels lose or gain from static (down the straightaway) to dynamic (in the middle of the turns) chassis attitude.)
Part II Parts.
ok, now its time for the good stuff[IMG]i/expressions/laugh2.gif[/IMG], Parts.
I'll start with the most basic of performance handleing parts, Wheels and Tires.
Wheels, ya know those shiny things holding your tires on. Some people call them rims, but thats just a throw back to the 50's and 60's when all wheels were steel and to dress them up people put crome rims on them to make them look pretty. Ok enough of the history lesson, up sized Wheels can both help and Hinder handleing. They help by replacing large areas of flexable rubber with relitivly inflexable metal. This can significantly reduce wheel/tire deflection in cornering (i.e. it stops the tire from bending to maximize the tires contact patch). Alloy wheels also help to cool your brakes, they are like big heat sinks helping reduce the risk of brake fade under hard braking, that and most alloy wheels are more open then stock thus letting more air in to cool the brakes down. If they are light enough, they can inprove acceleration and braking.
Tires, Dollar for dollar a good set of tires will boost you cornering abilities more then anny other part. Performance tires arn't cheep, but cost less then high performance tires, which in turn are cheaper then Ultra high performance tires. Race compound tires, Suprisingly, can cost less then Ultra high performance tires, however you must consider the cost per mile. Ultra hight performance tires, while offering the best traction for street tires, wear the quickest of all street tires. (approx 20,000 miles.) Race compound tires can be found in many DOT legal treads (Meaning that they are legal to use on the street) and if driven lightly may last you 10,000 miles.
Race compound DOT tires make gobs of traction, in the dry. When it's wet out forget it. you may as well have bald tires on ice. So think about where and when you intend to use a tire, then pick the right one for your needs. For those who intend to race, 1/4 mile or Autocross/Track Days, I highly recomend getting a second set of wheels and tires. Race compound tires while extreamly fun on the street will not last long and can be dangerous in the rain.
Shaving & Heat Cycleing
You may have heard of a tire being "Shaved" or "Heat Cycled". A Shaved tire, is just that, Shaved. the reason you would want to shave your tires is because any tread on your tire is only good for wet traction, and if you are so inclined dirt/offroad traction. Tread blocks also break up your contact patch in to smaller parts which can lead to tread block "Squirm"(just like how a tires side wall can bend and distort the contact patch, the tread it's self can bend and distort their individual contact patches. So by shaving the tread down you lessen the amount of squirm giving you better traction). Tread also gives you less rubber on the ground at any one time(this is why racing slicks are slick!). So your brand new tires will give you great wet traction but not as great dry traction,The Tire Rack offers a shaving service and will shave a tire to 3/32" which is the minimum tread depth legal for street use.
Heat Cycleing a tire is the process of heating a tire to opperating temp's and then letting it cool. the tire rack has this to say about it "The first time a competition tire is used is the most important. During that run, its tread compound is stretched, some of the weaker bonds between the rubber molecules will be broken (which generates some of the heat). If the tires are initially run too hard or too long, some of the stronger bonds will also be broken which will reduces the tire's grip and wear qualities. Running new tires through an easy heat cycle first, and allowing them to relax allows the rubber bonds to relink in a more uniform manner than they were originally manufactured. It actually makes them more consistent in strength and more resistant to loosing their strength the next time they are used. An important heat cycling step is that after being brought up to temperature, the tires require a minimum of 24 to 48 hours to relax and reform the bonds between their rubber molecules." Heat cycling happens naturally through out the life of a tire, every time you drive. Heat cycling has a draw back however, Each time a tire is heat cycled more of the rubber compound is converted in to carbon. The Carbon in turn makes the tire harder, making the tire stick less. This is a non-issue for race compound tires because they wear out long before the increaced carbon can affect traction. In street tires that are ment to last much longer then compitition tires this carbon increace can cause problems. As stated before A tire will tipically give you its best traction just before it wears out, but with heat cycleing a tire can lose traction long before the tread wears out. Some Tire's are affected by Heat cycling more then others.
Faster Acceleration through Smaller Tires
comeing soon.
Shocks & Springs
Contrary to popular belief, shocks don’t actually absorb shocks, but rather they dampen vibrations. The springs actually absorb shocks over bumps and control body roll. The shocks control the oscillations of the springs, determining how fast the spring moves up and down. Stiffer shock rates slow spring movements, while a softer shock rate allows the spring to move faster. Shaft speeds. Shocks work mostly with in a range of about 3 inches per second to about 20 inches per second. The lower speeds come in to play during weight transfer when the body is rolling or pitching. The high speeds come in to play over bumps and ruts. A shock manufacturer can alter low-,medium-, and high-speed valving to control what the shock does in different situations. Low- and medium-speed valving are used to control how the shock influences handling. When a shock is user adjustable, it is usually the low-speed valving that can be altered. Springs, are the heart of the suspension system . Springs perform five critical jobs. First, they keep the chassis and suspension from bottoming out over bumps. Second, they control the tires over bumps. Third, they control body roll during cornering, chassis squat during acceleration, and chassis dive under braking. Fourth, the springs determin how the load on the tires shifts during braking, cornering, and acceleration. (this makes them a pivotal component in establishing the nutral handling balance of the car) Finaly, the springs are the major factor in establishing the ride height of the chassis.
Anti-Rollbars/rollbars/swaybars ect.
Anti-roll bars are quite possably the best addition to cars since tires. They provide an excellent means for adjusting roll couple Distribution (Handling balance). they also control body roll, reducing camber change through corners. Of the two jobs that an Anti-Rollbar does, Adjusting the Roll Couple Distrobution is the MOST important. So just what is roll couple distribution? Simply put, roll couple distribution is the amout of roll resistance at the front of the car relative to the amount at the rear. Changing the roll couple distribution balance changes the handling balance of the car. If you increase the front roll resistance, the handling balance will change. If the car was neutral before the change, the car will now Understeer. If the car understeered prior to the change, it will understeer more, and if it oversteered, it will oversteer less after the change. The opposite effect occurs at the rear, where increasing rear roll resistance will increse oversteer or reduce understeer. The roll resistance can be increased by incerasing either the sping rates or the antiroll bar rates, or both. This makes roll resistance changes the key to finding a perfect steady-state handling balance. Adjustible antirollbars allow fin-tuning of the roll couple distribution making setup much easier.
I'll be covering How to Tune each part soon as well as an Intro in to Driving tecnieques/corner Theory soon. I just dont know when.
This Thread was started in response to the lack of knowledge and understanding of suspension and Performance Handling. Feel free to post any questions, disagreements or additions.
How to make your car handle well. Sounds easy, right? Just throw on some springs, upsized tires and Poof!!! Your car is now a screaming mountain eating demon. Well, not really. There is a lot more to Performance Handling then just buying aftermarket parts and slapping them on your car. So what can we do to improve oppon our little 7th. gen civic’s handling? The answer is, Lots! With just a little $ and proper tuning, you can make your civic do things a Mustang Cobra couldn’t even think of doing. Sure, you may not be able to beat a Cobra in the ¼ mile, but get him on a mountain road, and he’ll eat a tree long before you even come close to one. So back to the matter at hand. How do we make our cars the fastest on the mountain? The answer to that is a bit simpler then you think.
Part 1. Intro to Vehicle Dynamics
To get the maximum performance out of your car you have to first under stand Vehicle dynamics. Basically Vehicle dynamics are all of the things that affect the way your car handles, such as accelerating, braking, turning and various road surfaces and conditions. Most of this deals with weight transfer. When you accelerate, weight is transferred to the back, when you brake, weight goes to the front. And when you turn weight is transferred to the outside of the corner. The rest deals with your suspensions ability to keep the tires firmly planted on the ground and keeping the tire contact patch as large as possible.
1. Weight
So how does weight transfer affect the handling of your car? Weight directly affects tire traction. The more weight on a tire the more traction it will produce, to a point. (The ratio of weight to traction increase is not liner it’s more of a parabola, where the amount of traction gained with more weight decreases as more weight is applied. I.e. A tire with 100 lb placed on it will make 100 lb of traction, where a tire with 1000 lb will make 670 lb of traction). This is why a lighter car is inherently more maneuverable then a heavy car. The heavier car may produce more “total” traction, but the lighter car will make Proportionally more traction to its weight. That is our first advantage over the heaver V8s. Now you know how weigh affects traction, now we can apply that to handling.
When you accelerate, weight is transferred to the back tires, increasing their traction while the front tires lose traction, this loss of traction on the drive wheels is why FWD cars don’t do very well as dragsters. (It also makes a 10 sec FWD car all that more impressive). On a RWD car that natural weight transfer is a great bonus, by placing more weight on the drive wheels. When you are braking, weight gets transferred to the front, that’s why your front brakes are more important then your rears. The front tires gain traction and the rears lose traction. Finally when you turn, weight is transferred to the out side of the corner. This causes the outside tires to gain traction and the insides to lose traction. Now this action may seen ok, your gaining traction in one place and losing traction in an other, so the total traction should remain the same right? Well, No. But because the amount of traction gained/lost is not a liner function, the inner tires will lose traction quicker then the outer tires gain traction meaning, the total traction gained by placing more weight on the outside is less then the traction lost by the inside tires, equaling less total traction than if no weight transfer had occurred. Another problem with corner weight transfer is that the weigh does not get distributed equally front and rear. In our FWD cars more of the weight is placed on the front then the back. This is predominantly why our cars understeer.
So we can conclude that Weight transfer is bad for cornering. So how do we get rid of weight transfer? You can’t, even cars with no suspension such as Go Karts have to deal with weight transfer. You can however control where the weight is transferred, when it’s transferred and how fast it gets there.
Finally when dealing with weight there is Sprung and Unsprung weight, there is a big difference on how theses 2 types of weight affect handeling. Sprung weight are the parts of an automobile that are supported by the front and rear springs. They suspend the vehicle's frame, body, engine, and the power train above the wheels. Unsprung weight includes wheels and tires, brake assemblies, the rear axle assembly (If your car is RWD), and other structural members not supported by the springs. For handeling you want a low unsprung weight. The reason behind this is basic physics, F=ma. Force = Mass x Acceleration. If you’re wheels, tires etc. are heavy then it takes much more effort for your springs to keep the tires on the ground, if the unsprung weight is great enough the tire may leave the ground when it contacts a bump. And for you ¼ mile buffs, One pound of "unsprung" weight is equal to 8 pounds of "sprung" weight. For every 10 pounds of unsprung weight removed you may pick up as much as .01 seconds in quarter mile ET. So lighten those wheels, For track I wouldn't go bigger then a light weight 17 (Currently I run 17's on the street and Compititon 15's on the track,I autocross), on the strip, probably a light 14'.
2. Traction
Ok you now know how weight affects traction, but what exactly is “traction”. Traction is the tires ability to grip the road, and a tire only has so much traction. Tires make traction though friction between the rubber molecules at the tire contact patch and the road surface. And as discussed before, traction increases as vertical load on the tire increases, which is why aerodynamic downforce works so well. Lastly, a tire will make more traction if the entire contact patch is equally loaded. There are 5 characteristics that affect traction. 1. Basic tire design and construction. 2. Sidewall rigidity. 3. Tread rubber compound. 4. Tread design. And 5. Tire size. Of these characteristics we only have a choice of Tire size, compound and Tread design. We can also control the tires pressure, camber, toe in/out and camber change (Camber Change is the number of degrees of camber that wheels lose or gain from static (down the straightaway) to dynamic (in the middle of the turns) chassis attitude.)
Part II Parts.
ok, now its time for the good stuff[IMG]i/expressions/laugh2.gif[/IMG], Parts.
I'll start with the most basic of performance handleing parts, Wheels and Tires.
Wheels, ya know those shiny things holding your tires on. Some people call them rims, but thats just a throw back to the 50's and 60's when all wheels were steel and to dress them up people put crome rims on them to make them look pretty. Ok enough of the history lesson, up sized Wheels can both help and Hinder handleing. They help by replacing large areas of flexable rubber with relitivly inflexable metal. This can significantly reduce wheel/tire deflection in cornering (i.e. it stops the tire from bending to maximize the tires contact patch). Alloy wheels also help to cool your brakes, they are like big heat sinks helping reduce the risk of brake fade under hard braking, that and most alloy wheels are more open then stock thus letting more air in to cool the brakes down. If they are light enough, they can inprove acceleration and braking.
Tires, Dollar for dollar a good set of tires will boost you cornering abilities more then anny other part. Performance tires arn't cheep, but cost less then high performance tires, which in turn are cheaper then Ultra high performance tires. Race compound tires, Suprisingly, can cost less then Ultra high performance tires, however you must consider the cost per mile. Ultra hight performance tires, while offering the best traction for street tires, wear the quickest of all street tires. (approx 20,000 miles.) Race compound tires can be found in many DOT legal treads (Meaning that they are legal to use on the street) and if driven lightly may last you 10,000 miles.
Race compound DOT tires make gobs of traction, in the dry. When it's wet out forget it. you may as well have bald tires on ice. So think about where and when you intend to use a tire, then pick the right one for your needs. For those who intend to race, 1/4 mile or Autocross/Track Days, I highly recomend getting a second set of wheels and tires. Race compound tires while extreamly fun on the street will not last long and can be dangerous in the rain. Shaving & Heat Cycleing
You may have heard of a tire being "Shaved" or "Heat Cycled". A Shaved tire, is just that, Shaved. the reason you would want to shave your tires is because any tread on your tire is only good for wet traction, and if you are so inclined dirt/offroad traction. Tread blocks also break up your contact patch in to smaller parts which can lead to tread block "Squirm"(just like how a tires side wall can bend and distort the contact patch, the tread it's self can bend and distort their individual contact patches. So by shaving the tread down you lessen the amount of squirm giving you better traction). Tread also gives you less rubber on the ground at any one time(this is why racing slicks are slick!). So your brand new tires will give you great wet traction but not as great dry traction,The Tire Rack offers a shaving service and will shave a tire to 3/32" which is the minimum tread depth legal for street use.
Heat Cycleing a tire is the process of heating a tire to opperating temp's and then letting it cool. the tire rack has this to say about it "The first time a competition tire is used is the most important. During that run, its tread compound is stretched, some of the weaker bonds between the rubber molecules will be broken (which generates some of the heat). If the tires are initially run too hard or too long, some of the stronger bonds will also be broken which will reduces the tire's grip and wear qualities. Running new tires through an easy heat cycle first, and allowing them to relax allows the rubber bonds to relink in a more uniform manner than they were originally manufactured. It actually makes them more consistent in strength and more resistant to loosing their strength the next time they are used. An important heat cycling step is that after being brought up to temperature, the tires require a minimum of 24 to 48 hours to relax and reform the bonds between their rubber molecules." Heat cycling happens naturally through out the life of a tire, every time you drive. Heat cycling has a draw back however, Each time a tire is heat cycled more of the rubber compound is converted in to carbon. The Carbon in turn makes the tire harder, making the tire stick less. This is a non-issue for race compound tires because they wear out long before the increaced carbon can affect traction. In street tires that are ment to last much longer then compitition tires this carbon increace can cause problems. As stated before A tire will tipically give you its best traction just before it wears out, but with heat cycleing a tire can lose traction long before the tread wears out. Some Tire's are affected by Heat cycling more then others.
Faster Acceleration through Smaller Tires
comeing soon.
Shocks & Springs
Contrary to popular belief, shocks don’t actually absorb shocks, but rather they dampen vibrations. The springs actually absorb shocks over bumps and control body roll. The shocks control the oscillations of the springs, determining how fast the spring moves up and down. Stiffer shock rates slow spring movements, while a softer shock rate allows the spring to move faster. Shaft speeds. Shocks work mostly with in a range of about 3 inches per second to about 20 inches per second. The lower speeds come in to play during weight transfer when the body is rolling or pitching. The high speeds come in to play over bumps and ruts. A shock manufacturer can alter low-,medium-, and high-speed valving to control what the shock does in different situations. Low- and medium-speed valving are used to control how the shock influences handling. When a shock is user adjustable, it is usually the low-speed valving that can be altered. Springs, are the heart of the suspension system . Springs perform five critical jobs. First, they keep the chassis and suspension from bottoming out over bumps. Second, they control the tires over bumps. Third, they control body roll during cornering, chassis squat during acceleration, and chassis dive under braking. Fourth, the springs determin how the load on the tires shifts during braking, cornering, and acceleration. (this makes them a pivotal component in establishing the nutral handling balance of the car) Finaly, the springs are the major factor in establishing the ride height of the chassis.
Anti-Rollbars/rollbars/swaybars ect.
Anti-roll bars are quite possably the best addition to cars since tires. They provide an excellent means for adjusting roll couple Distribution (Handling balance). they also control body roll, reducing camber change through corners. Of the two jobs that an Anti-Rollbar does, Adjusting the Roll Couple Distrobution is the MOST important. So just what is roll couple distribution? Simply put, roll couple distribution is the amout of roll resistance at the front of the car relative to the amount at the rear. Changing the roll couple distribution balance changes the handling balance of the car. If you increase the front roll resistance, the handling balance will change. If the car was neutral before the change, the car will now Understeer. If the car understeered prior to the change, it will understeer more, and if it oversteered, it will oversteer less after the change. The opposite effect occurs at the rear, where increasing rear roll resistance will increse oversteer or reduce understeer. The roll resistance can be increased by incerasing either the sping rates or the antiroll bar rates, or both. This makes roll resistance changes the key to finding a perfect steady-state handling balance. Adjustible antirollbars allow fin-tuning of the roll couple distribution making setup much easier.
I'll be covering How to Tune each part soon as well as an Intro in to Driving tecnieques/corner Theory soon. I just dont know when.
Last edited by Zzyzx; 06-23-2003 at 03:14 PM.
12-14-2002
#2
Registered!!
iTrader: (1)
Join Date: Feb 2002
Location: Eugene, Oregon, US
Posts: 197
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Good right up I might add.
Suspensions use various links, arms, and joints to allow the whells to move freely up and down; front suspensions also have to allow the front wheels to turn. All suspensions must provide for the side to side, and the front to back wheel support. The lighter the wheel/tire combination, the lower the "unsprung weight" and the better the ride and handling of the vehicle. All springs share Hooke's Law, which states that the force exerted by the spring is directly proportional to the amount the spring is deflected- spring rate. Anyway I was bored.
Suspensions use various links, arms, and joints to allow the whells to move freely up and down; front suspensions also have to allow the front wheels to turn. All suspensions must provide for the side to side, and the front to back wheel support. The lighter the wheel/tire combination, the lower the "unsprung weight" and the better the ride and handling of the vehicle. All springs share Hooke's Law, which states that the force exerted by the spring is directly proportional to the amount the spring is deflected- spring rate. Anyway I was bored.
12-18-2002
#3
Registered!!
Join Date: Jun 2001
Location: Fresno, California, US
Posts: 457
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Hey....I...I feel ripped off! I mean, heres this great article with information, but....I wanted more!
Zzyzx, tell me more! How, in technical terms, will a rear tie bar help or hinder? A front strut bar, an RSX rear sway conversion? The height of the drop on lowering springs? Adding or re-distributing weight within the vehilce to help with handling. Tell us more!! We are told what performance parts do, but what about specifically for the 7th gen chassis? What are low dollar things that we can do on a spare staurday or two that can give us a respectable increase in handling? How do we spank that naughty cobra without shelling out the money to buy one ourselves? I demand to know!!!
Zzyzx, tell me more! How, in technical terms, will a rear tie bar help or hinder? A front strut bar, an RSX rear sway conversion? The height of the drop on lowering springs? Adding or re-distributing weight within the vehilce to help with handling. Tell us more!! We are told what performance parts do, but what about specifically for the 7th gen chassis? What are low dollar things that we can do on a spare staurday or two that can give us a respectable increase in handling? How do we spank that naughty cobra without shelling out the money to buy one ourselves? I demand to know!!!
12-20-2002
#5
Registered!!
iTrader: (1)
Join Date: Aug 2001
Location: Car Audioville, Quebec, Canada
Age: 43
Posts: 6,202
Likes: 0
Received 1 Like
on
1 Post
Rep Power: 0 He's working on how to tune these aspects..like how sway bars, buhshings, spring rates, ride heights, chassis stiffness, Bound and rebound affect things...or at leasy I hope he is [IMG]i/expressions/face-icon-small-smile.gif[/IMG]
01-16-2003
#8
Ask me about your mom.
Join Date: Jul 2002
Location: Ottawa, Ontario, Canada
Posts: 2,563
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 291 for those of you who want more suspension info...checkout www.turnfast.com.
They have a bunch of great articles on how to turn fast.
A great read for everyone!
They have a bunch of great articles on how to turn fast.
A great read for everyone!
04-29-2003
#12
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Originally posted by BlueRevs
Spoken like a true SCCA member. Great lesson, and didn't have to pay tuition for it
Spoken like a true SCCA member. Great lesson, and didn't have to pay tuition for it
oh, wait, Nevermind......
05-25-2003
#17
Registered!!
Join Date: Oct 2002
Location: SoCal
Posts: 320
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 So I wonder, other than the weight factor, what else is it that can make our car out-maneuver a Cobra then? Isn't understeer bad when cornering? If both cars are properly tuned, which would emerge as the better performer?
05-28-2003
#19
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Originally posted by Renamazazo
The better driver...
The better driver...
exactly, all the performance tuning, Horse power and suspension you have dont mean Squat if you don't know how to drive it. Probably the best and cheepest way to learn the limits of your car and your self is autocrossing. Trust me, you never push your car as hard on the track as you do on the street. EVER. I say this because unless you can take a set of tires designed to last 10,000 miles on the street and destroy them in 5 hours(or approximatly 300 miles), then you are not coming any where near the level that you can achieve at the track.
Performance handling is as much Driver skill as it is chassis tuning.
05-29-2003
#21
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Originally posted by orion_squall
hi,
strut bar enhence chassis, will it increase comfort of ride?
hi,
strut bar enhence chassis, will it increase comfort of ride?
06-22-2003
#22
Registered!!
iTrader: (1)
Join Date: Jun 2003
Location: Nor Cali
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Sorry if these questions has been asked before, but I am new to the forums:
1. Whats the difference between Strut Bars vs Sway Bars?
2. Do you need both?
3. I see alot of people with strut bars and tie bars but not alot of people with sway bars... any comments?
1. Whats the difference between Strut Bars vs Sway Bars?
2. Do you need both?
3. I see alot of people with strut bars and tie bars but not alot of people with sway bars... any comments?
06-23-2003
#23
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Originally posted by ib2ez2
Sorry if these questions has been asked before, but I am new to the forums:
1. Whats the difference between Strut Bars vs Sway Bars?
2. Do you need both?
3. I see alot of people with strut bars and tie bars but not alot of people with sway bars... any comments?
Sorry if these questions has been asked before, but I am new to the forums:
1. Whats the difference between Strut Bars vs Sway Bars?
2. Do you need both?
3. I see alot of people with strut bars and tie bars but not alot of people with sway bars... any comments?
simple answers.
1. Strut bars are a chassis reinforcement made to reduce flex in the body of the car they are also known as Tie bars when struts are not present on the car like in earlier generations of civics. Sway bars/Anti-sway bars/Roll bars/anti-rollbars are all the same thing, they are a suspension modification like springs, in fact they do many of the same things as springs.
2. do you need both? well no, and yes. it depends on what you are planing to do with your car. do you just want a more solid feel while driving? Get Strut bars. Do you want a corner eating demon? Get both.
3. the reason you dont see alot of people with Roll bars, is because people dont under stand their importance to performance handling. See, because of their name, Anti-Rollbars, people assume that their only purpous is to reduce body roll. Their actual primary use is to adjust Roll Couple Distribution.
06-24-2003
#25
Registered!!
Join Date: Jan 2002
Location: Houston, Texas, US
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 something that you've failed to mention in your write-up is bigger is NOT better in terms of sway bar diameter.
simply put, a car with a very high spring rate and large sway bars will not handle well. econo cars come fromt he factory with slower spring rates and small sway bars. you can't beef up everything and expect a race car.
a simple formula:
low spring rate + large diameter bars = good
low spring rate + small diameter bars = bad
high spring rate + large diameter bars = bad
high spring rate + small diameter bars = good
upgrading just a stock rear bar will create oversteer, and depending on the ratio of the diameters between the Front and Rear, too large of a rear bar will create SNAP oversteer. this usually occurs at highway speeds. trying to turn suddenly, say to avoid a chunk of tire, will create so much oversteer that the rear of the car comes out. this is extremely dangerous. just as lowering a car too far past the peak performing center of gravity will reduce handling, improper suspension tuning in all areas, can make for a very unsafe vehicle.
for small FWD cars that weigh between ~2400-3000 lbs a ratio of Front to Rear diameters should be around 5:4. again the characteristics of the whole suspension are dependent upon eachother. a 5:4 is a good ratio for a car with a low spring rate(but still more agressive than stock) that has stiffer shocks. you will want a slightly lower ratio for a car with a high spring rate and stiffer struts.
FYI- the amount of a drop a spring provides has nothing to do with it's spring rate, except for coilover sleeves like ground controls. the lower you drop a car using sleeved coilovers, the higher the spring rate.
if you have any questions feel free to contact me at marcgerth@hotmail.com i don't usually post here expect to check up every so often.
simply put, a car with a very high spring rate and large sway bars will not handle well. econo cars come fromt he factory with slower spring rates and small sway bars. you can't beef up everything and expect a race car.
a simple formula:
low spring rate + large diameter bars = good
low spring rate + small diameter bars = bad
high spring rate + large diameter bars = bad
high spring rate + small diameter bars = good
upgrading just a stock rear bar will create oversteer, and depending on the ratio of the diameters between the Front and Rear, too large of a rear bar will create SNAP oversteer. this usually occurs at highway speeds. trying to turn suddenly, say to avoid a chunk of tire, will create so much oversteer that the rear of the car comes out. this is extremely dangerous. just as lowering a car too far past the peak performing center of gravity will reduce handling, improper suspension tuning in all areas, can make for a very unsafe vehicle.
for small FWD cars that weigh between ~2400-3000 lbs a ratio of Front to Rear diameters should be around 5:4. again the characteristics of the whole suspension are dependent upon eachother. a 5:4 is a good ratio for a car with a low spring rate(but still more agressive than stock) that has stiffer shocks. you will want a slightly lower ratio for a car with a high spring rate and stiffer struts.
FYI- the amount of a drop a spring provides has nothing to do with it's spring rate, except for coilover sleeves like ground controls. the lower you drop a car using sleeved coilovers, the higher the spring rate.
if you have any questions feel free to contact me at marcgerth@hotmail.com i don't usually post here expect to check up every so often.
06-24-2003
#26
Registered!!
Join Date: Jan 2002
Location: Houston, Texas, US
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Originally posted by Zzyzx
simple answers.
1. Strut bars are a chassis reinforcement made to reduce flex in the body of the car they are also known as Tie bars when struts are not present on the car like in earlier generations of civics. Sway bars/Anti-sway bars/Roll bars/anti-rollbars are all the same thing, they are a suspension modification like springs, in fact they do many of the same things as springs.
2. do you need both? well no, and yes. it depends on what you are planing to do with your car. do you just want a more solid feel while driving? Get Strut bars. Do you want a corner eating demon? Get both.
3. the reason you dont see alot of people with Roll bars, is because people dont under stand their importance to performance handling. See, because of their name, Anti-Rollbars, people assume that their only purpous is to reduce body roll. Their actual primary use is to adjust Roll Couple Distribution.
simple answers.
1. Strut bars are a chassis reinforcement made to reduce flex in the body of the car they are also known as Tie bars when struts are not present on the car like in earlier generations of civics. Sway bars/Anti-sway bars/Roll bars/anti-rollbars are all the same thing, they are a suspension modification like springs, in fact they do many of the same things as springs.
2. do you need both? well no, and yes. it depends on what you are planing to do with your car. do you just want a more solid feel while driving? Get Strut bars. Do you want a corner eating demon? Get both.
3. the reason you dont see alot of people with Roll bars, is because people dont under stand their importance to performance handling. See, because of their name, Anti-Rollbars, people assume that their only purpous is to reduce body roll. Their actual primary use is to adjust Roll Couple Distribution.
strut bars reinforce the chasis for greater rigidity.
sway bars reinforce the struts for great rigidity. they act as a spring between the struts, and the diameter and mounting points all factor in to how they perform.
06-24-2003
#27
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Originally posted by mazdamx3rs
they are not the same thing
strut bars reinforce the chasis for greater rigidity (Reduced Chassis flex)
sway bars reinforce the struts for great rigidity. they act as a spring between the struts, and the diameter and mounting points all factor in to how they perform.
they are not the same thing
strut bars reinforce the chasis for greater rigidity (Reduced Chassis flex)
sway bars reinforce the struts for great rigidity. they act as a spring between the struts, and the diameter and mounting points all factor in to how they perform.
Strut bars are a chassis reinforcement, and are only called strut bars on cars with McPherson strut type suspension and only when they attach to those strut mountings. I.E. the shock tower of the 7th gen civic, other wise they are called Tie bars. You want a rigid chassis because other wise the flexing of the chassis will act like a Giant undampered spring and make tuning the suspension Virtuially impossible.
An anit-roll bar is not a chassis reinforcement. it is a suspension component that does 2 main jobs. 1. it helps the springs to better resist body roll, thus reducing camber change durring cornering thus increacing traction. 2. Increaces(or decreaces) the roll resistance on that end of the car (Font or rear) to adjust the Roll couple distribution of that car Just like haveing springs with Higher or lower spring rates would.
And I agree, you cant just beef up every thing and expect the car to handle well. you have to spend time tuning just like if you were tuning an engine. Also, on the street it would be very dangerous to have a car with a 50% roll Couple distribution, 58% front would be safer, where the car would still want to Understeer at its extreams. How can you find out what roll couple disribution % you car is at? well with out the proper measurments and equations (or softwear) you'll never know. I'd like to find out personally so I just may sit down and figure it out one day. but like mazdamx3rs posted
low spring rate + large diameter bars = good
low spring rate + small diameter bars = bad
high spring rate + large diameter bars = bad
high spring rate + small diameter bars = good
in general that is.
mazdamx3rs, its nice to see some one with some experiance tuning suspension.
do you do any sort of racing? Like club racing or Autocross?
06-24-2003
#28
Registered!!
Join Date: Jan 2002
Location: Houston, Texas, US
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 thanks for the kind words.
i just got into autoXing in December of 2002. i actually got a 02 protege rather than a 02 civic because i felt that the mazda chasis was better suited for track racing and more responsive to low budget mods. my brother (TXGA) has a 01 coupe and i was just not impressed. with just a few mods: strut bar, eibach prokit and falken azenis, i'm at the top of my class right now. i actually got 1st place the last time i competed
my friend's Mazda MP3 would beat me if she could just drive it. 
i realize that you probably already knew the differences in strut bars and sways bars, i was just trying to clear up some generalities with more specific generalities
it was quite refreshing to see such an informative introduction to suspension tuning on this site.
i'm hoping to build a road racing car with my brother in a few years.
i assume you participate in SCCA events also?
i just got into autoXing in December of 2002. i actually got a 02 protege rather than a 02 civic because i felt that the mazda chasis was better suited for track racing and more responsive to low budget mods. my brother (TXGA) has a 01 coupe and i was just not impressed. with just a few mods: strut bar, eibach prokit and falken azenis, i'm at the top of my class right now. i actually got 1st place the last time i competed
my friend's Mazda MP3 would beat me if she could just drive it. i realize that you probably already knew the differences in strut bars and sways bars, i was just trying to clear up some generalities with more specific generalities
it was quite refreshing to see such an informative introduction to suspension tuning on this site.
i'm hoping to build a road racing car with my brother in a few years.
i assume you participate in SCCA events also?
06-24-2003
#29
Autocross Junky
Hey! Look At Me!! I'm a Supporting Member!!
Thread Starter
Join Date: Oct 2002
Location: Las Vegas, Nevada, US
Age: 45
Posts: 7,211
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 356 Ya, I do Solo 2 events (Autocross) here in Las Vegas. I ended up with the civic mostly because i needed a car that I wouldnt have to fix very often. originaly I didn't intend to race it. But it ended up being my only car and I was hurtin for some racing so I started running it. Much to my Dismay when I found out about the lack of performance options for the New model. Most of my time here is spend trying to get the 1/4 mile people to try their hand at corners. The Protige has allways been a good chassis for autocross, The MP3 is also a good chassis. It seems that Mazda has spend a lot of time trying to make performance minded cars. I wish Honda did the same.
06-26-2003
#30
Registered!!
Join Date: Feb 2003
Location: TX
Posts: 202
Likes: 0
Received 0 Likes
on
0 Posts
Rep Power: 0 Originally posted by mazdamx3rs
for small FWD cars that weigh between ~2400-3000 lbs a ratio of Front to Rear diameters should be around 5:4. again the characteristics of the whole suspension are dependent upon eachother. a 5:4 is a good ratio for a car with a low spring rate(but still more agressive than stock) that has stiffer shocks. you will want a slightly lower ratio for a car with a high spring rate and stiffer struts.
for small FWD cars that weigh between ~2400-3000 lbs a ratio of Front to Rear diameters should be around 5:4. again the characteristics of the whole suspension are dependent upon eachother. a 5:4 is a good ratio for a car with a low spring rate(but still more agressive than stock) that has stiffer shocks. you will want a slightly lower ratio for a car with a high spring rate and stiffer struts.
