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Old 12-07-2006, 02:04 PM   #1
ButtDyno
Street's closed, pizza boy
 
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06 Evo #7 STU, 03 IS300

Default The OFFICIAL Swaybar & Endlink FAQ !

Swaybar/Endlink FAQ

This is the first of hopefully several FAQ’s about common suspension upgrades for the Impreza. Unlike Ron I am not going to be doing most of the writing myself, but deferring to and quoting from people who are much smarter than I am. I am following Ron’s basic format since he’s a smart guy and has had a lot of success with it

Ron did do one of these, here:
http://forums.nasioc.com/forums/showthread.php?t=920405
I wanted to go into more depth about some of the relevant issues, and also wanted to have one FAQ dedicated to the express purpose of swaybars. I'm also doped up on Vicadin.

DISCLAIMER:

Swaybars, like most suspension modifications, will change how your car handles, especially in emergency situations. Whenever you modify your suspension you should find a controlled environment so you can get used to how your car’s handling behavior has changed. Swaybars, in particular, can make your car a lot more likely to “snap” suddenly in a turn under certain conditions. Modify with care! It is your responsibility to know your car and to know how to drive your car.

What do swaybars do?

Cliffnotes: Swaybars, also known as anti-roll bars or stabilizer bars, limit the independence of your suspension in order to change the amount of body roll the car will exhibit in sharp turns. This can have a noticeable impact on the car’s overall balance (i.e. its tendency to oversteer or understeer).

Hotchkis Tuning explains briefly:
Quote:
One very potent product that yields a very good ‘bang-for-the-buck’ is a stabilizer Bar, or more commonly referred to as an Anti-Roll Bar (ARB). One probably asks, “Okay, just what is it, and what does it do?” An ARB is a round piece of metal, either solid or tubular, that connects both the left and the right sides of the suspension together. Typically cars will have one of these bars in the front and one in the rear of the vehicle. The bars react to body roll, or lean, by twisting. During a corner, the body of the vehicle tries to ‘lean’ or ‘fall’ over. Each ARB twists against the ‘lean’, causing a reaction force that equates to a ‘lifting’ force on the outside body, and a ‘downward’ force on the inside body. This helps to even the pressure generated by a corner, across both tires. The even pressure helps improve handling by making more traction or ‘grip’ available to the driver.


HowStuffWorks has a good overview of the basic tech as well:
http://auto.howstuffworks.com/question432.htm
Quote:
Stabilizer bars are part of a car's suspension system. They are sometimes also called anti-sway bars or anti-roll bars. Their purpose in life is to try to keep the car's body from "rolling" in a sharp turn.
Think about what happens to a car in a sharp turn. If you are inside the car, you know that your body gets pulled toward the outside of the turn. The same thing is happening to all the parts of the car. So the part of the car on the outside of the turn gets pushed down toward the road and the part of the car on the inside of the turn rises up. In other words, the body of the car "rolls" 10 or 20 or 30 degrees toward the outside of the turn. If you take a turn fast enough, the tires on the inside of the turn actually rise off the road and the car flips over.
Roll is bad. It tends to put more weight on the outside tires and less weigh on the inside tires, reducing traction. It also messes up steering. What you would like is for the body of the car to remain flat through a turn so that the weight stays distributed evenly on all four tires.
A stabilizer bar tries to keep the car's body flat by moving force from one side of the body to another. To picture how a stabilizer bar works, imagine a metal rod that is an inch or two (2 to 5 cm) in diameter. If your front tires are 5 feet (1.6 meters) apart, make the rod about 4 feet long. Attach the rod to the frame of the car in front of the front tires, but attach it with bushings in such a way that it can rotate. Now attach arms from the rod to the front suspension member on both sides.
When you go into a turn now, the front suspension member of the outside of the turn gets pushed upward. The arm of the sway bar gets pushed upward, and this applies torsion to the rod. The torsion them moves the arm at the other end of the rod, and this causes the suspension on the other side of the car to compress as well. The car's body tends to stay flat in the turn.
If you don't have a stabilizer bar, you tend to have a lot of trouble with body roll in a turn. If you have too much stabilizer bar, you tend to lose independence between the suspension members on both sides of the car. When one wheel hits a bump, the stabilizer bar transmits the bump to the other side of the car as well, which is not what you want. The ideal is to find a setting that reduces body roll but does not hurt the independence of the tires.
Grassroots Motorsports also has a good article on the subject:
http://grassrootsmotorsports.com/art...-less/#more-78

Will swaybar [x] fit my car?

See here:
The "Will this suspension part fit my car?" thread

Which manufacturer is best?

Swaybars are pretty much swaybars. You pick them based on solid vs. hollow, what diameter is appropriate for your application, and whether it fits your car. That’s about it. Really there are only three things that can make a swaybar “bad”:
1. If you choose the wrong one for your application.
2. If it doesn’t fit your car properly (i.e. it requires hacking to fit, or hits your exhaust, or whatever)
3. If it isn’t fabricated well and is known to break.


Who manufactures them?

Whiteline, Cusco, Addco, Perrin, Cobb/Hotchkis, Subaru (sometimes an OEM bar from one car can help out a lot on another car) and others.

What is better, hollow or solid?

There is no “better”.

The advantages of hollow bars are:
1. They are lighter (less unsprung weight).
Here’s a document by Hotchkis explaining their philosophy:
http://www.hotchkis.net/product_development.html

The disadvantages of hollow bars:
1. There aren’t very many choices. The Hotchkis bars (and the Cobb bars which are, AFAIK, rebranded Hotchkis bars), and the Addco bars are the only ones that I know of.
2. They are less stiff for a given diameter. A 29mm solid bar is stiffer than a 29mm hollow bar. The 32mm Strano front swaybar is equivalent to a 29.6mm solid bar. This depends on the wall thickness of the bar, so without knowing that you cannot automatically apply a magic number to a hollow bar to figure out its equivalent solid bar.
3. There is more risk of the bar fatiguing. This has happened to some hollow bars, but to the best of my understanding it was isolated to only a handful of cases.
4. They are usually more expensive than the equivalent solid bar.

Here’s a document from Whiteline explaining their philosophy (they prefer solid):
http://www.whiteline.com.au/docs/bul...%20Swaybar.pdf

When making this decision, you need to first figure out what size bar you need. If you feel that a 22mm is appropriate for your application you have options, since there are “equivalent” bars from both available in that size. But there are fewer equivalently-large hollow bars, other than the 32mm Strano bar, which is not available for all cars.

Once you’ve figured out the size you want, you can decide if a hollow bar is even possible, and if it is, you can decide whether you would rather save money or save unsprung weight.

Here’s a decent thread about hollow vs. solid:
http://forums.nasioc.com/forums/showthread.php?t=918653
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Last edited by Matt A; 09-28-2010 at 09:46 AM.
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Old 12-07-2006, 02:05 PM   #2
ButtDyno
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Default

What size swaybar should I get?

1. Consider your other modifications.

If you already have a very stiff car (for instance, you’re running coilovers with very high springrates) you will have less body roll than someone with a softly sprung car. As such you will not need as big a swaybar for the same effect. Suspension tuning is very much a black art. Some like to go with softer springs and stiffer swaybars, some like to go with stiffer springs and relatively soft swaybars, and some like to make everything massively stiff and see what happens.

Also, if you are running a fairly aggressive alignment (for instance, lots of negative camber up front) you might not need as big a swaybar for the same reasons.

The point is - your suspension is a SYSTEM. You cannot make decisions in a vacuum – the whole system must be considered when you are changing things. This also means you should think about upgrading both of your swaybars rather than just the rear or just the front.

2. Consider your starting point.

Most of the turbo Imprezas come with a 20mm front swaybar and a 13-20 (??) mm rear swaybar. Wagons typically come with smaller rears than sedans.

Here's a list of known stock swaybar sizes:
http://forums.nasioc.com/forums/show...6#post12006426

3. Consider your application.

First, here’s an excellent post by Turn In Concepts on the subject:
http://forums.nasioc.com/forums/show...96&postcount=5
Quote:
As for what size bars to get, and this is my opinion based on experience, and is in consideration of solid bars (that's what I have the most experience with, and it makes for an easier comparison to stock).

For the rear bar - 22mm is good. You can pull off 24mm but the inside tire gets too light, and you lose traction in hard turns if you are on the stock springs. If you are considering going to 24mm or larger then you really really need to consider upgrading your springs first. See, the springs will stiffen not only the ride, but will also increase roll resistance. Now, stiffer springs does not have to mean a crappy ride. If you do your homework, and get a spring that a) doesn't have a stupidly low drop and b) are good for the operating range of your struts then the ride will feel just fine.

For the front - traditional thinking has held that if you want to fix understeer you want the rear to step out more. While this does work to some extent, I feel this is the wrong way to approach it. Sure CONTROLLABLE oversteer with the back stepping out is fun, and a good thing, but the front is still going wide. As part of this traditional thinking folks scream get a bigger rear bar, and leave the front alone or go smaller. I have to disagree on this. Here's why -

First, let's look at the technical reason. The dynamic camber curve for the mcpherson strut setup sucks. It just does. That's a tradeoff of running this type of setup, and all setups have their good and bad points. What happens is this - you enter a turn at speed. Your ourside front corner gets loaded with weight. That weight compresses the suspension. When the suspension compresses the camber of that wheel, where that tire is loaded, rolls toward positive camber. If you're running very little static negative camber this will actually start to make the inside edge of the tire light, reducing the width of your effective contact patch that resists lateral acceleration. This lose of traction results in that "push" or understeer condition. This is why folks who are more into performance run a decent amount of negative front camber. Sure, they give up some straight line accel and decel grip doing this, but that's more than offset by the fact that they can maximize the width of the contact patch in turns to help resist higher slip angles due to lateral acceleration. If you lower the car any with springs or coilovers that camber curve gets worse. Oh, and the added bumpsteer sucks too. Fortunately the fine fellows at 6Gun have figured out a way to help that, but that's for a different long post I'll most like use to answer somebodies questions in the next few days.

So, what they heck the the point in my saying all that? Well, let's get back to the front swaybar. The front swaybar will increase the effective spring rate of the wheel without effecting the ride spring rate. In other words, it will help keep the suspension from compressing so much at the loaded corner. Less compression means less loss of camber. Less loss of camber means that you can tune to, and maximize the contact patch of the tire to resist that push. Now, one of the things you need to consider - just like you can't make something from nothing, you can't make a good contact patch if you have nothing to give it to begin. Because the suspension will still compress some you need some negative camber in the front to start with. See the bajillion threads on alignment specs for where to start.

Now, for the second item I'd like to bring up something I've thought long and hard about for a long time. For ease I'll call it the philosphical side of the front suspension. Here's what we've got - a car that understeers or pushes quite a bit. Sure, you could throw a big bar in the rear and get the rear end to step out to help eliminate that understeer, but I feel that this is the wrong approach. The front of the car is still pushing, but the rear just happens to be stepping out at a faster rate than the front. The net result is a wider than what I feel is necessary lateral travel of the car. In other words, the rear is whipping around to point the front of the car where you want it to go, but the front of the car is still sliding sideways and taking the whole thing sideways making for a wider path than really is needed.

See, this stems from my philosophy that move oversteer does not necessarily mean less understeer. The front is still pushing. I feel the fix for this is to setup the front end of the car to truly reduce understeer as much as possible. This will make the front tuck in more, and while your tires will be resisting more lateral acceleration taking more grip from straight line acceleration (think traction circle), you'll be able to unwind from the turn faster thus getting you back toward the acceleration portion sooner than your competition. In other words, you'll be able to drive a tighter, and more controlled line.

Additionally, by reducing understeer as much as possible you won't have to set up the car for so much oversteer. This will also lead to more control, a tighter line, and the ability to accelerate sooner.

Now, that's great an all, but if you're looking for a simple answer as to what size bar to get then here it is (I'm giving these in terms of whiteline bars as I am most familiar with them):

Rear - 22mm to 24mm, but if you go to 24mm then you really want to think hard about upgrading your springs. If you go higher than 24mm then you are taking the wrong approach and trying to fix shortcomings of your springs with swaybars, and this is not the right way to do it. Get a proper spring for what you do, and then fine tune with a swaybar.

Front - for the street and mild autocross, and mild track work look at 24mm up front. If you start to get into it more then 26mm is good (WL makes a 24-26 adjustable front). These are also very good sizes if you are not a smooth driver as they won't make things too "darty" with super quick tuck of the front end into the apex. For autocross junkies or track whores who are smooth overall and can anticipate the "dartiness" then look at the 27 to 29mm front bar.

Now, two last thing on these considerations: You need a brand and size, and you need a vendor.

For the brand and size please do some research in the car parts review area. After receiving the parts you choose, and installing them please leave your feedback on them in the car parts review area so you can help others in the future.

The vendor part works the same way. Please research the vendors you are considering in the vendor review area. After the completion of the transaction please leave your feedback for that vendor in the vendor review area so that you can again help others in the future.

Today's message brought to you by the letter G and the number 32354956.
I tried but I really can’t say it any better than that. Thanks TiC!

Clint has another writeup about this on IWSTI:
http://www.iwsti.com/forums/suspensi...ngs-clint.html

One additional note – the bigger you go, the more likely it is that you’ll hear random clunking/popping noises from the front of your car. I think this generalization is true, but feel free to correct me

I’ve heard that a bigger front swaybar will make the car understeer. Is this true?

It is, and it isn’t. Basically, for our cars with their Macpherson strut configuration, the benefit that a front swaybar gives you in terms of managing camber under load outweighs the putting-too-much-weight-on-the-tire drawback.

DrBiggly has practiced this speech many times and has gotten pretty good at it:

http://forums.nasioc.com/forums/showthread.php?t=879235
Quote:
Originally Posted by DrBiggly
To answer your question directly, you get a +3 or +4 addition in front grip from the camber curve improvement but a -1 in front grip from the "additional weight on the tire" part of the equation that comes from having a larger bar, so overall traction in the front of the vehicle is increased. Of course body roll is decreased, but as a bonus turn-in is quicker.

The car feels like it is understeering less because the limit of grip is a lot higher, while in reality at the limit the car is actually understeering a bit more. Hence why some folks say the car understeers less on a bigger front bar, and then others who haven't tried it bust out the "book and GT4" knowledge and proclaim that a bigger front bar will make the car understeer more.
I *REALLY* recommend reading that thread. It’s an excellent discussion of the topic.

For a much longer post by DrBiggly about the front swaybar (i.e. if you don’t believe him and you think a bigger front swaybar is a bad idea for our cars), here is a longer version of that post:
http://forums.nasioc.com/forums/show...54&postcount=4

Will this swaybar fit my car?

From the failed “Will this fit my car” thread:

http://forums.nasioc.com/forums/show....php?t=1083256
Quote:
Originally Posted by Scooby921
WRX sedan and wagon RSB's are interchangable. WRX's can use STi RSB's, but they will mount to the outside of the endlinks. WRX and STi FSB's are interchangable. Wagons use different FSB's than sedans and can't swap.
There are some exceptions. This is a weak part of this FAQ, so feel free to suggest additions.

The big-ass 27mm Whiteline has been made to fit on a 2002 WRX Wagon:
http://forums.nasioc.com/forums/show....php?t=1004827

How do adjustable swaybars work?

A swaybar will come with multiple sets of holes at the end, where the bar attaches to the endlinks. Here’s an old picture of my Cusco bar, which is said to be the equivalent of a 22, 23 or 24mm bar depending on which hole is selected:



Basically – the longer you make the bar, the softer it is. Short but sweet thread:
http://forums.nasioc.com/forums/showthread.php?t=859144

The nice people from Whiteline chimed in with their explanation:
http://forums.nasioc.com/forums/show....php?t=1089202
Quote:
Originally Posted by WL Flatout
"A swaybar is actually a torsion spring not unlike a coil spring. Imagine you could uncoil your coil springs, and then hold each end and twist. This is pretty much what happens with the coil when it does its work as the shape forces the material to twist through out its length as it's compressed.

Going back to our straightened piece of spring steel, with your arms holding each end, imagine that each of your arms represent the swaybars "arms" and the spring steel rod represents the "back" or centre portion of the bar between the arms. As you try to twist the ends, a certain amount of flex happens in your arms but most of the action happens across the back of the bar. Hence, the formula calculating swaybar rates requires a value for the length of the back of the bar as well as the length of the arms.

The formula does not allow for a left or right arm value, just a total that acknowledges that the total arm length vs. the back length is the key calculation affecting the rate. We know that shortening the effective length of the arm by choosing a hole closer to the back of the bar will reduce the leverage ratio hence increase the rate but this affects the total arm length so can be done on one side only. In this way, a 2 hole per arm Blade adjustable bar does actually have 3 different settings; a 3-hole bar has 5 different settings. Additional mounting holes on the chassis end multiply the options further.

There are some assumptions and exceptions to these examples, specifically the issue of ultra short arm lengths and its effect on suspension preload. That is, asymmetric adjustment can preload the suspension if the arms are very short. The other issue is that the bars arms also deflect so that is taken into account by the formula but the amount of deflection is governed by the size and shape. Friction and deflection in mounting bushes will also affect the bars outright behaviour.

You may also notice that some of our adjustable use a longer Blade (flattened area) than others. We use this to fine-tune the adjustment range as the Bladed portion deflects a lot less than the simple round bar. (Think of a structural steel I-beam). Even the height and width of the Blade is used to tune the final outcome when designing new bars.

It's therefore important to understand that a 22mm physical diameter swaybar can be made to behave like something totally different just by changing the shape of the bar and its ends. Adjustable bars are a very useful suspension balance tuning tool and a better understanding of how they work should help you get a better result".
So, a bigger rear bar makes the rear end step out earlier but doesn't help the front, right?

I got this PM and felt it was worth posting:
Quote:
This is incorect. Increasing the rear bar size does not just make the rear step out earlier, with no benefit to the front. When you are in a hard left hand turn, most of the cars' weight is on the right hand wheels,...if you had a big front sway bar and no rear bar,...the front right tire would be overloaded, and the front left would have almost no weight on it at all,...it might even be airborne.

The rear tires would both have weight on them however, the right more than the left of course. Adding a rear bar would take weight off the left rear and add it to the right rear. IT WOULD ALSO REDUCE THE TOTAL BODY ROLL OF THE CAR. This would in turn take some weight off the overloaded right front tire (allowing it to grip slightly better), and add weight to the left front tire,...which until now, was not able to help the car around the corner much, if at all.

The net effect is that the rear bar will certainly cause the rear to step out sooner that it would have with no rear bar (or with a smaller rear bar),...but at the same time, the front WILL have MORE grip.

You need to increase the rear bar size until you almost achieve a neutral car,...and if you still have too much body roll,...you increase both bars from there. (This might only involve buying an aftermarket front bar and moving the endlinks inboard on the aftermarket rear bar you already have).

Last edited by ButtDyno; 03-03-2009 at 06:34 PM.
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Old 12-07-2006, 02:05 PM   #3
ButtDyno
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Why should I upgrade the endlinks?

Two reasons:
1. You want to get the most of what swaybar you have. The stock stuff is usually pretty flexible.
2. Your stock ones won’t handle the bar you’re using.

I’m stealing this from Ron’s FAQ:
http://forums.nasioc.com/forums/show...&highlight=faq
Quote:
Originally Posted by Unabomber
In order to discuss the function of end links, one has to consider how they work in conjunction with a sway bar. The entire purpose of a sway bar is to act as a torsion spring. In order to do this you need some way to twist it. That twisting ability is provided by a bent "lever" at each end of the bar and allowing that lever to be pushed and pulled by attaching it to a suspension component that moves up and down. Since we're talking about the rear we'll look there. In our case, the attachment points that Subaru uses is on the rear lateral link. Basically, the end links connect the lateral link to the sway bar. When the lateral link moves up and down, it provides force on the drop link, which provides force on the sway bar. This twists the bar, and allows it to do its job. All of this is fine except for two problems. First, the length of the stock links may cause some problems with the fuel filler tube, and second they are way too soft. With full suspension travel, you run the risk of the end of the sway bar hitting the fuel fill neck. This is especially true if your car is lowered. Also, the stock rear links are made from plastic. The OEM unit flexes quite easily, even under minor loads.

Aftermarket rear end links help solve these two problems: some feature a length that is shorter than the stock links to solve the fuel filler neck problem, and they are considerably stiffer than the stock links. Made with bodies that are water jet cut from aluminum, extruded aluminum, or CNC manufactured, they are incredibly stiff when compared to the stock pieces. This stiffness in turn allows the motion from the rear suspension to be applied to the rear bar. This allows the sway bar to operate to its full potential, and apply forces where necessary.
The KartBoy endlinks are almost certainly the #1 seller in the Subaru community, because we love tom@kartboy and he makes great stuff. There are others, too.

Turn in Concepts explains some of the reasons you might want to upgrade:

http://forums.nasioc.com/forums/show...6&postcount=18
Quote:
Originally Posted by Turn in Concepts
Ok, let me see if I can sum this up to clear up any confusion
- Rear endlinks on both the wagon and sedan are plastic, and really should be upgraded. Even with the stock bar they will deflect too much and hurt performance.
- Rear sway mount - the 04+ imprezas have beefier mounts than the pre-04 models. Many suggest upgrading these mounts while you are under there. The most cost effective solution is to get the real Subaru parts for this. You can get these through your dealer or through someone like Jamie at subarugenuineparts.com (who will be cheaper than just a dealer. One thing to note on upgrading the mounts. If you get the 04+ D-bushing hoops too you will need to order an 04+ rear swaybar as the bushing style is different between the 02-03 and the 04+.
- Front endlinks - On a wagon these are a platic dogbone. It is a good idea to upgrade them. On a sedan these are metal, and are quite good even for running some of the larger front sways out there.
Also, some bars (like the 32mm Strano) come with their own specialized endlinks and flat out will not work with the stock ones.

Conclusion
I hope this helps people. I might be a moderator but that doesn’t mean I know a ****ing thing about suspensions, so feel free to submit any corrections. It will not hurt my feelings

Last edited by ButtDyno; 12-07-2006 at 02:12 PM.
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Old 12-07-2006, 02:05 PM   #4
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Installation tips

How to install aftermarket rear swaybar mounts:
http://forums.nasioc.com/forums/show...1#post19550029

The passenger side swaybar mount is an unholy pain in the ass unless you use the trick listed above. Do this... don't force it!!

Last edited by ButtDyno; 10-01-2007 at 12:26 PM.
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Old 12-07-2006, 02:05 PM   #5
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How stiff are the Cobb hollow bars?

http://www.iwsti.com/forums/suspensi...ay-set-up.html
Quote:
Originally Posted by RaceComp Engineering View Post
I did do the calculation....it's about 23.5mm solid in the front, and the rear is around 22.x, 23.x, and 24.x in the rear. I forget exactly and I have the exact numbers at home.

[room for expansion]

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Old 12-07-2006, 04:27 PM   #6
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Awesome!
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Old 12-07-2006, 05:37 PM   #7
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Oh hey!!! Look at that!!! Good work Mr. ButtDyno, sir.
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Old 12-07-2006, 06:10 PM   #8
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Indeed! And thank you to my newest vendor! ^^^^ You're the man, Clint!
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Old 12-07-2006, 08:27 PM   #9
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Good job, great consolidation of material!

I did notice one thing though, and I was surprised to see this information in both the Hotchkis and HSW page... body roll is a function of weight transfer... and weight transfer is not a function of body roll. I think their descriptions of how a swaybar works are incorrect. Weight transfer is only a function of track width, lateral acceleration, and cg height. Speed of weight transfer is where the swaybars come in, and larger bars actually speed up the weight transfer to cause the tires to be more unevenly loaded than with nominal bars. So when those sources say that swaybars work by keeping the tires more evenly loaded... that's incorrect.

The primary reason why roll reduction is desirable is because it keeps our alignment closer to where it will perform best (helps lessen camber loss). There is actually a tradeoff happening with a larger bar... we take a hit in grip with the increased rate of weight transfer, but get a benefit by maintaining alignment angles. The benefit of alignment outweighs the negative of weight transfer.

I guess another reason roll reduction is desirable is because roll can be unsettling to the driver, and a lot of roll usually means a soft, slowly-responding suspension that doesn't settle in time before the next maneuver.
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Old 12-07-2006, 09:40 PM   #10
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Holy crap!

Great info!

p.s. Now I see that you have so much time when the woman is out of the house
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Old 12-08-2006, 09:29 AM   #11
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Quote:
Originally Posted by Mind View Post
Good job, great consolidation of material!

I did notice one thing though, and I was surprised to see this information in both the Hotchkis and HSW page... body roll is a function of weight transfer... and weight transfer is not a function of body roll.
This?

Hotchkis: "Each ARB twists against the ‘lean’, causing a reaction force that equates to a ‘lifting’ force on the outside body, and a ‘downward’ force on the inside body. This helps to even the pressure generated by a corner, across both tires. The even pressure helps improve handling by making more traction or ‘grip’ available to the driver."

Howstuffworks: "Roll is bad. It tends to put more weight on the outside tires and less weigh on the inside tires, reducing traction. It also messes up steering. What you would like is for the body of the car to remain flat through a turn so that the weight stays distributed evenly on all four tires."

Yeah, this is something I hope to touch on in the brake FAQ as well (just because your car is braking "flatter" doesn't mean the amount of weight transfer has changed). Maybe I'll replace that section with something out of a proper textbook or something.

john
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Old 12-08-2006, 04:39 PM   #12
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Quote:
Originally Posted by ButtDyno View Post
This?

Hotchkis: "Each ARB twists against the ‘lean’, causing a reaction force that equates to a ‘lifting’ force on the outside body, and a ‘downward’ force on the inside body. This helps to even the pressure generated by a corner, across both tires. The even pressure helps improve handling by making more traction or ‘grip’ available to the driver."

Howstuffworks: "Roll is bad. It tends to put more weight on the outside tires and less weigh on the inside tires, reducing traction. It also messes up steering. What you would like is for the body of the car to remain flat through a turn so that the weight stays distributed evenly on all four tires."

Yeah, this is something I hope to touch on in the brake FAQ as well (just because your car is braking "flatter" doesn't mean the amount of weight transfer has changed). Maybe I'll replace that section with something out of a proper textbook or something.

john

Yes, that's what I was referring to. Same principle with the braking that you mention.
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Old 12-09-2006, 10:33 AM   #13
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<-perrin rear sway bar with mounts and endlinks...Never heared a thing from them...silent as can be and def one of the best suspensions mods you can do.

to be honest though, I liked the front sway bar upgrade better than the rear.

I upgraded to a mild helix bar. whiteline bushings and just installed some noltec links last night. when i first installed the bar last year, i got on the high way and it was like a completely different car. SO solid up front compared to stock. I cant wait to get out and testdrive my car with the new noltecs which are super beefy blingy
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Old 12-09-2006, 02:59 PM   #14
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Good job! Needed to be done.


- Andrew
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Old 12-09-2006, 05:56 PM   #15
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Stab bars owe their effectiveness to the nonlinear behavior of tires to provide cornering force (actually cornering stiffness) with increased normal load. The cornering stiffness vs. normal load curve is initially linear but goes concave down in the higher normal load range. This means that a pair of tires can provide the most lateral force if they are evenly loaded and conversely there is a reduction in total lateral force capability of a pair of tires as load is transfered from one to the other.

So if a stab bar causes an increase in the load transfer across the tires on a given axle and there is a reduction in lateral force generation capability, then why do we use them? Because at the same time, the other end of the car is transfering less load and therefore is picking up lateral force capability (remember that the total load transfer is fixed for a given lateral acceleration of the vehicle, it is just the front to back distribution which we can play with.)
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Old 12-09-2006, 06:06 PM   #16
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I'm learning a lot about my car from reading these FAQs. All I need now is a twisty road to test my upgrades.


<---Flat area.
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Old 12-28-2006, 10:21 PM   #17
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With regards to endlinks, spherical bearings or not?
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Old 12-31-2006, 01:37 AM   #18
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Quote:
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With regards to endlinks, spherical bearings or not?
^^^ bump for answer, I want to know too, and i don't think it was covered.

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Old 12-31-2006, 01:41 AM   #19
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great thread
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Old 12-31-2006, 01:24 PM   #20
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How did I miss this? Nice kill buddy and great MS Paint h4x0r skillz!
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Old 01-18-2007, 11:53 AM   #21
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Great FAQ, thanks.
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Old 01-18-2007, 12:16 PM   #22
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its a great faq, teh only thing i'm still curious about is what stiffness thesee adj bars are at each setting

1. can a bar thats a 22mm adj , be less than 22 mm solid stiffness on its first setting?
2. would a 22 adj from whiteline with 3 setttings for example be 22-23-24?
(i've been looking at the 22 adj rsb vs 24 adj and don't know if i'm looking at a 20-24 bar vs 22-26 bar or a 22-24 bar vs 24-26 bar..(i'm on upgraded springs)
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Old 01-18-2007, 12:31 PM   #23
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Step 1: anti-roll bar, not swaybar.

Nice write up.

Chris H.
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Old 01-18-2007, 10:14 PM   #24
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Quote:
Originally Posted by ButtDyno
Cliffnotes: Swaybars, also known as anti-roll bars or stabilizer bars,
It's like the fender brace thing. It might be wrong but it's a better search term

john

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Old 01-18-2007, 10:18 PM   #25
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Originally Posted by uathatis View Post
its a great faq, teh only thing i'm still curious about is what stiffness thesee adj bars are at each setting

1. can a bar thats a 22mm adj , be less than 22 mm solid stiffness on its first setting?
2. would a 22 adj from whiteline with 3 setttings for example be 22-23-24?
(i've been looking at the 22 adj rsb vs 24 adj and don't know if i'm looking at a 20-24 bar vs 22-26 bar or a 22-24 bar vs 24-26 bar..(i'm on upgraded springs)
Basically, it depends on the bar, and how the people who make the bar decide to market it. The Cusco "22-23-24" is actually one of those diameters (probably 22?) and it can be made to have the approximate stiffness of a 24 if you put it to a different setting.

I think that if it says "27mm adjustable" that 27 is usually the minimum but you'd have to ask the manufacturer. It's also not guaranteed that it will move in 1mm increments.

john
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