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Better handling WITHOUT a rear sway bar! by Boostdreamer
Started on: 01-10-2014 11:15 AM
Replies: 44 (3151 views)
Last post by: Steven Snyder on 05-17-2014 12:44 AM
Boostdreamer
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Report this Post01-10-2014 11:15 AM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
Of my three drivable Fieros, my current daily driver handles the best! It is an 86 GT automatic, almost all stock with about 70K miles. All new rubber motor mounts except for the dogbone and it was removed and replaced with my best one. It has decent tires which means good tread but not the most expensive. It had an alignment a few months ago but since then I've changed the caster and dropped the cradle out twice. It does not have a rear sway bar.

My first two drivers were notchbacks and my first one came with a TFS rear sway bar installed. The previous owner had wrecked it and wanted to unload it. It was an 87 V6 Getrag 5-speed. I didn't find any suspension damage and just added new motor mounts, an alignment, and pumped up the tires. It drove fine. That car had a serious desire to swap ends in a turn. It spun out several times on me. My son ended up wrecking and totaling it.

I pulled the good parts off and bought another notchback. This one was also an 87 but it had a Duke/Isuzu setup. I drove it for a while and one day added the rear swaybar to it. Then it was easy to spun out in that car, too. My GT has never felt like it wanted to spin out. It has always felt like it was going to go where I pointed it. Maybe there are other factors involved but I feel no need to add that TFS rear sway bar to my GT. It handles very well without it and I don't want to do anything that could reverse that.

Fieros seem to have "all or nothing" handling personalities. Owners will either say their car "handles like it is on rails" or they say "the bump steer is so bad they don't like driving it". I have never once read about a Fiero with so-so handling!

1. Tell us if your car handles well or poorly.
2. Tell us if it has a rear sway bar or not and if so, what kind.

Maybe we can see a pattern here. If you have any tips about sway bar installation, post those too. Maybe sway bars are "tuneable" and they have to be dialed in to work properly.

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Jonathan

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Report this Post01-10-2014 12:10 PM Click Here to See the Profile for zmcdonalSend a Private Message to zmcdonalEdit/Delete MessageReply w/QuoteDirect Link to This Post
What was the condition of your front bar mounts and end links on your cars with a rear bar? Make sure those are in good shape. Or upgraded to poly or Rodney's zero lash links.

When adding a rear bar it will increase oversteer characteristics but it also reduces understeer where the front wants to just plow through a corner.

My 85 handled awesome with an added fiero store bar, but I also added poly mounts and Rodney's links on the front. It made a huge difference in handling and you definitely have to be a little careful with it until you get use to the change.

My 87 appears to have addco bars both front and back and it handles pretty great to, hard to compare the two because I didn't have them at the same time.

I will say this, I don't plan to own another fiero without a rear bar. They make upgraded front bars, and some people say they need to be put on in pairs. Maybe if you upgrade your front bar as well you will be happier with the results.

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[This message has been edited by zmcdonal (edited 01-10-2014).]

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Report this Post01-10-2014 12:34 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have to assume the front links were original. I have no other knowledge about their condition. The rear links were original red poly on the first car. The bar did not look very old. It should have been well inside its envelope of servicability.

When I put the bar on the second car, I replaced the links and the poly bumpers with new ones.

It also seems to me that a rear sway bar reduces the suspension travel of the control arms. Think about it. The control arms move up and down with their pivots toward each other and the center of the car. Any given point on them is going to travel in a lateral arc as the suspension moves. A sway bar is a device that ties those two control arms together at like points and is designed to pivot at a 90* angle to them. The ends of the sway bar will be traveling in transverse arcs as it pivots. Doesn't this sound like a perfect situation for binding?

Jonathan
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Report this Post01-10-2014 12:49 PM Click Here to See the Profile for SynthesisSend a Private Message to SynthesisEdit/Delete MessageReply w/QuoteDirect Link to This Post
The end links are what provide the movement needed for the swaybar to pivot/twist up when the suspension moves.

My 86SE Frankencar had both the front/rear TFS Swaybars with poly end links and bushings.
The car handled like a dream and the only time I was able to spin it was quite by accident while going around a corner in a snow storm.

The new to me 86 GT has a stock front sway bar (until I move the front from the old car) and the TFS rear bar.
It handles just fine and has never swapped ends on me, but it is definitely more twitchy.

You need to keep the balance right. Slapping a rear sway bar in with a stock diameter front bar throws the balance off.
Swapping a rear bar in, and beefing up the front with a thicker bar and better links/bushings keeps the balance and plants the car better.

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Report this Post01-10-2014 12:57 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
Does TFS sell a front bar? I wonder why they didn't make their rear bar compatable with the stock front? I bet this is a common cause of handling problems. I think my car handles great right now without the bar. My experience has been that the addition of only a rear bar greatly upsets the balance. I wish I could drive my car back-to-back with a Fiero that has upgraded front and rear sway bars. I'd like to see if there is any feeling of difference.

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Report this Post01-10-2014 01:01 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
If a car without a rear bar handles better than 2 others with rear bars I would guess the 2 others may have had bad rear struts, or loose cradle bolts, or bad alignment??

My 2m4 has an Addco in the rear, it made a huge difference, I'd say something like 40% better.

Installed just like this:
http://www.michiganfieroclub.com/files/swaybar.pdf

[This message has been edited by 2.5 (edited 01-10-2014).]

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Report this Post01-10-2014 01:05 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
I just checked the TFS website and they do not offer a front sway bar as a stand alone item. They do have one as part of a total suspension upgrade package. I think they have their marketing backwards. If they are going to offer either sway bars separately, it should be the front. To only add the rear is irresponsible since it overpowers the front stock bar.

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Report this Post01-10-2014 01:20 PM Click Here to See the Profile for zmcdonalSend a Private Message to zmcdonalEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

If they are going to offer either sway bars separately, it should be the front. To only add the rear is irresponsible since it overpowers the front stock bar.

Jonathan


If you upgrade only the front bar it will make understeer worse. There would be no need to upgrade just the front bar.
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Report this Post01-10-2014 01:25 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by zmcdonal:


If you upgrade only the front bar it will make understeer worse. There would be no need to upgrade just the front bar.


Valid point.

I guess what they need to do is offer a matched pair and state that they are available separately as replacements. Either that or design one that is compatable with the original front.

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Report this Post01-10-2014 01:43 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
This was posted by TimGray back in 06
 
quote

some people have spun out more in autocrossing with a rear swaybar on a fiero than without.

The car tends to be more prone to spinning in a very hard turn with the swaybar because it removes some of the understeer and it's now easier to get past the point of no return.

if you are planning on autocross, I would research it further and talk to others about it for more information.


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Report this Post01-10-2014 02:39 PM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

A sway bar is a device that ties those two control arms together at like points and is designed to pivot at a 90* angle to them. The ends of the sway bar will be traveling in transverse arcs as it pivots. Doesn't this sound like a perfect situation for binding?

Jonathan


Itsn't that why it works though, the only thing binding is the bar and its bushings?
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Report this Post01-10-2014 03:22 PM Click Here to See the Profile for aaronkochClick Here to Email aaronkochSend a Private Message to aaronkochEdit/Delete MessageReply w/QuoteDirect Link to This Post
On my 88 L36, I purposely do NOT have a rear bar. It honestly handles better. The whole car has KYB's, lowering springs, and nice wide/good rubber. Also, I moved the battery up front.

Stepping out the rear is fully controllable, whereas with a rear bar it was almost a snap when it let go. Cornering limits are higher, and corner transitions are smoother. I challenge ANYBODY with a good suspension setup to drive their favorite track or road with the bar, then disconnect it (even temporarily) and redrive the course/road. It rides smoother and handles better without the bar.

My previous fiero, and '86 se with the 3.4 was downright terrifying with the rear bar. Took it off and the car became sane again.

I believe that sometimes people make the mistake of believing that because it "feels tighter" it must be handling better. That is simply not true, and when you use a rear bar to load up the outside wheel you end up with inside wheelspin and you're not allowing the rear suspension to do it's job over mid-corner imperfections.

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[This message has been edited by aaronkoch (edited 01-10-2014).]

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Report this Post01-10-2014 05:42 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Different strokes for different folks. If having only a front sway bar works for you, then that's fine. Some people may feel differently, though.
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Report this Post01-10-2014 06:11 PM Click Here to See the Profile for DonPClick Here to visit DonP's HomePageSend a Private Message to DonPEdit/Delete MessageReply w/QuoteDirect Link to This Post
Our Lemons car handles noticeably better without a rear bar. The car was based on a Formula that obviously had the rear bar. What I can say however is that we did NOT have the stagger in tire size that the '88 originally had. I cannot say what difference that might have made.

I ran the car at Sear Point for 5-6 laps to get a base feel/experience. We then re-attached the rear bar (it was mounted with no end links attached for the base run) and I did another 4-5 laps. It was immediately obvious to me that the car was twitchier. Much more apt to snap loose. But I did a couple laps in order to have more confidence in my impressions. Obviously it was most acute on turns such as turn one where the car is cresting a hill while turning. So there was some unloading of the suspension. I wanted to use the rear bar and believed it would help.

We did not retest this when the springs were later radically changed. So I can only speak to that static situation.

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Report this Post01-10-2014 07:08 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
You can easily make a Fiero have high handling limit with no issues. Rear Bar, bigger wheels and tires. Better struts etc. This is a no brainer.

What is difficult is to get the Fiero to handle at the limit and still be easy to drive. The tuning and control at the limit is the real issue.

I have driven many a great handling car and the one trait is that they make going fast on bad roads easy. GM for many years would sell you a car that at the limit would pull a big G number but would be a white knuckle ride on any secondary road at high speed. Bump steer issues, poor jounce control and too stiff of a ride with shocks/struts or springs that are too stiff.

While you can improve and fix a lot of the Fiero issues with better tires, struts and bushings it can still leave something's on the table. Not many here can properly tune a car to get it to many modern day handling cars. Much of it is done on shaker rigs and with computer programs none of us have. Also we would not want to spend the money it would take.

Finally the one key I find in those who think the Fiero is the end all be all handling car is that they have never driven a properly tuned modern car. GM during their days building the GM Performance Division cars have learned how to properly tune a performance car for real world driving away from Warrens Black Lake. Now they have dispended the GMPD they have moved these tuners to the platform programs to where they design in the right stuff from the start and not have to go in and fix what was never right. Engineers like Mark Stielow at GM have brought the correct thinking the often less is more. Less shock and less spring or even less tire can often lead to a much better overall handling car. This is something that the Euro companies have known for years.

Stiff cars are great if you are on the track but for a car in the real world it pays a price. The new Magna shocks on many of the GM cars give you the best of both worlds but that does little to tame a older GM car.

To fix the Fiero you have to add a rear bar and proper matching front bar to the car. Better shocks and struts that are not too stiff help keep the tires planted on uneven surfaces.
Finally to help control bump steer you have to stiffen up the bushings in the back. Some so it different ways. Herb Adams used solid bearing bushings in the rear control arms on the 84-87 cars. He also used solid sub frame bushings . On a 84 you need to really rework the tie rods in the back like they did on the 85 or you will get deflection of the body to the sub frame.

There is more you can do. but these are some of the basics.

I used to think that all GM cars were great handling as they were better than my 1970 old Monte Carlo. But I learned after driving some of the worlds best and autocrossing some great cars just what true great handling was. When you are going down a road and it feels like 45 MPH and it is 100 MPH and you are not working hard to keep the car under control you know you have a good car. Now when you feel like you are driving 45 and it feels like 100 MPH then you know you have some work to do.

Take a look at the CTS sport that just came out and learn what GM did there This is their new thinking and the way to really make a car handle. Even with out the Magntic shocks the car is still one of the best out there. The neat thing is they did it even with a softer ride and smaller tires.

We sell a lot of suspension kits at work and many of the top names like Hotchkiss and others. You can see that bigger is not always better and matching the parts to the needs of the car and the road are key.

The Fiero was just born at a bad time where it just did not get the development money to fix the suspension till 1988. You can compare the 85 to an 88 and learn what the car lacked even back in the day. Today they would even do the 88 different but that is another deal all together. If you want a Fiero to handle better just buy an 88 or pattern the changes and alignments after an 88. The Fiero is never going to be a C7 but you can still have a fun to drive car that is not a lot of work to keep on the road.
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California Kid
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Report this Post01-10-2014 11:26 PM Click Here to See the Profile for California KidSend a Private Message to California KidEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

Maybe we can see a pattern here. If you have any tips about sway bar installation, post those too. Maybe sway bars are "tuneable" and they have to be dialed in to work properly.



The pattern is as follows: Rebuilt the entire suspension, including anything that is attached to the suspension. Do the research to determine additional changes that suit your driving style, and your intent for the car (this contain many, many items).

Just slapping a rear sway bar on a old car with more than 20 years on it, isn't going to do what you expect it to, you have to do your homework. The Fiero can still deliver some very impressive cornering performance, just don't try to compare it with modern day sports cars costing a lot of money, the Fiero is vintage, and should be thought of it that way. I don't hear of any Shelby Cobra owners comparing there cars to modern day sports cars, something to think about.

There have been many articles in the past about adding a rear sway bar, which did improve corning of the Fiero, when it was done correctly.

[This message has been edited by California Kid (edited 01-10-2014).]

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Report this Post01-11-2014 07:20 AM Click Here to See the Profile for davegSend a Private Message to davegEdit/Delete MessageReply w/QuoteDirect Link to This Post
Before adding a rear bar it would be wise to ensure the tires, shocks and struts are in good shape. Then bushings, and alignment. Then look at the in teed use of the car and change handling to suit.

I've been having fun with solo2 or auto cross since about 96, and the fiero pushes quite a lot. I started with front bar bushings and links, made it push more. Added a rear bar for much quicker turn-in, but my favorite is working with alignment, a bit of toe out front, and zero rear for quick, predictable handling. That is great for solo2, perhaps not for everyone.

Single best suspension improvement: Koni

I've driven lots of other cars, and nothing communicates or is as fun as my fiero. If a Miata would have the torque of a V6, then maybe...

Dave
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Report this Post01-11-2014 08:53 AM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
Like stated just do not slap on a rear bar from some other source and think it is golden.

I have seen many where they have taken front bars and put them in the rear and while it may help it is not what you would call properly tuned. Most companies of the years have made rear bars but they also make a front bar to keep the car balanced.

In my Case I have the Herb Adams VSE bars that were designed for the Fiero his company showroom stock raced for a time back in the 80's. The car was given a inch and a quarter rear bar but to get the best balance it required a one inch front with a stern warning that it was ok to use the front bar but do not use the rear bar without installing the front bar.

Companies spend thousands of hours and hundreds of thousands of dollars to tune car suspensions and if it were so easy to do on your own everyone would have it sorted out. Improving a suspension is easy but like I said getting it right is the hard part as the tuning to get it right is difficult.
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Report this Post01-11-2014 09:00 AM Click Here to See the Profile for California KidSend a Private Message to California KidEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by daveg:

Before adding a rear bar it would be wise to ensure the tires, shocks and struts are in good shape. Then bushings, and alignment. Then look at the in teed use of the car and change handling to suit.

I've been having fun with solo2 or auto cross since about 96, and the fiero pushes quite a lot. I started with front bar bushings and links, made it push more. Added a rear bar for much quicker turn-in, but my favorite is working with alignment, a bit of toe out front, and zero rear for quick, predictable handling. That is great for solo2, perhaps not for everyone.

Single best suspension improvement: Koni

I've driven lots of other cars, and nothing communicates or is as fun as my fiero. If a Miata would have the torque of a V6, then maybe...

Dave


All excellent points Dave. Fully agree with you on Koni making a remarkable difference. Also somewhat contained in your post is another key factor, which is driver experience on a race course, this is where you learn more about what the car is doing, and make adjustments to improve it.
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Report this Post01-11-2014 10:50 AM Click Here to See the Profile for IMSA GTClick Here to Email IMSA GTSend a Private Message to IMSA GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
I personally would go with sway bars from Paul at HHP. He sells them in the mall and although they are a little more expensive, there are a lot of adjustments that can be made to his depending on how you drive your car.
http://www.fiero.nl/forum/Forum4/HTML/036556.html

HHP Front Sway Bar Kit:


HHP Rear Sway Bar Kit:



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Report this Post01-11-2014 11:40 AM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
I found that thread in my research. Looks and sounds like very good products. I contacted R Runner in another current thread and confirmed that he is still offering them.

There is more talk here about cars used on tracks and courses. I'd like to hear more experiences about street driven cars and the owners' opinion about the handling. Was there anyone else out there like myself and the guy I bought my first Fiero from, who also thought that the addition of a rear sway bar was a no-brainer upgrade?

[This message has been edited by Boostdreamer (edited 01-11-2014).]

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Report this Post01-12-2014 02:11 PM Click Here to See the Profile for jon mSend a Private Message to jon mEdit/Delete MessageReply w/QuoteDirect Link to This Post
All I can say is that I added a fierostore sway bar on the rear some time ago along with new shocks poly bushings front and back to the car and the difference as members on here predicted was night and day from the old bushings and shocks this year will be different again when I take the car out as it is lowered in the front and has coil overs in the back.

when I had the car before I changed out the shocks and the old bushings - one day I was driving in the rain and I went around a corner at about 10 mph and I ended up facing the other way.

but it does seems evident that it really depends on how you drive your fiero and on what the conditions are

maybe and I say this as I am not near the car that the fierostore's swaybar is matched to the front - is it the same diameter bar to start with - I wouldn't of thought they would of just made a swaybar without any research but stranger things have been done in the past

the fiero was built many moons ago - before traction and launch controls where implemented as they are today on modern cars

just my contribution

jon

[This message has been edited by jon m (edited 01-12-2014).]

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Report this Post01-12-2014 03:09 PM Click Here to See the Profile for R RunnerClick Here to visit R Runner's HomePageClick Here to Email R RunnerSend a Private Message to R RunnerEdit/Delete MessageReply w/QuoteDirect Link to This Post
For what's it worth....

Cali Kid put it very well. You need to go through an make sure that everything is functioning properly. I, like many people, started with the Addco front and rear bar along with TFS equipment. I found that with the adjustable Konis, the car was not balanced unless I ran full stiff in the back end and full soft up front. My driving style? Maybe, but what was the point of adding a rear bar of the rear shocks still need to be stiffened up to compensate? Anyway, I started adapting a 1.25" bar from GM trucks to fit in the back of the Fiero. My first attempts lost a lot of ground clearance and I decided to engineer a better mounting design. I sold those bars for a while such that they were generally balanced with the Addco front bar. Now I am making (when I have time) the adjustable ones. They are night and day better than the previous generation of bar that I made.

But this is not a sales pitch. Back on topic...

My point is that many people talk about the bar diameter. True, it is very important, but a sway bar links each side of the suspension through torsion. Torsion = force X distance, so the length of the bar arm is critical. A 1.25 solid bar is pointless with a 20" lever arm. Likewise, you could not even attempt to drive a bar of that thickness that had an 8" long lever arm. There is a lot of thought that needs to go in to a suspension design..... especially if it was working right in the first place and an individual decides to "improve" it. That target can be elusive because either the driver does not understand what the result of the changes will be or effect, OR they really don't know what they want the car to feel like in the first place.
Many people think that "ultimate handling" is the goal. Really? Define that. On an asphalt surface with no cracks, or a road rally car on dirt? These are completely different suspension designs let alone tuning. Generally we in this crowd thing of asphalt "road racing" type street performance, but want a reasonable ride comfort. THAT is difficult to manage.

The key is front to rear balance NOT just increased stiffness. If I want that, I'll just weld the A-arms to the frame... For what it is worth, I offer bars that are only slightly stiffer than stock but well balanced. I have never sold a set.

So back to the point of our Fieros, in general, handling better without a rear bar. It all depends on the driver.
The addition of a Addco rear bar increases the rear stiffness side to side on a stock '84 to '87. Stiffening the rear will make the car more "loose" than it was. Stiffening up the front will make a car "push" more than it was. With a rear heavy car like ours, a rear bar that is too stiff is more difficult to control during heavy deceleration especially while setting up for a turn and it will tend to kick out more during a turn and acceleration.

I prefer a neutral handling car. One way I test mine is to get in a big, clean, parking lot and turn the steering wheel all the way to one side so that it is just short of hitting the steering lock. If there is just one person in the car (driver) then the best direction may be to the left. Slowly accelerate the car. Now, SLOWLY accelerate the car. 1 mph per revolution after about 20 mph should do it. What end starts to break free first? Is the car starting to push? Does the back end come out? If you are pushing, soften up the front or stiffen the rear. If you are loose (back end comes out first) then stiffen the front or loosen the rear. There are many ways to do this including tire pressure, tire compound, tire side wall, tire width... (notice all the tire "stuff" )... shock rate, spring rate, or sway bar rate to name a few. You will notice that if you accelerate at this point, your car may act a certain way and different if you decelerate from this point. I prefer that all 4 wheels slide the same amount when doing this test. If nothing else, it is a good starting point.
BTW.... the same test can be done in the rain or on a wet parking lot. Heck, even ice will work. The biggest difference in surface is speed. The car does not drive differently. Don't fool yourself.
Dynamically, going into a turn or out of a turn, these friction points change, but a good neutral set up at steady state is a good start.


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Boostdreamer
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Report this Post01-12-2014 04:56 PM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
I definately agree with the neutral handling setup goal. I don't know how or when having the rear come around would be beneficial. That to me is not a matter of "how you drive your car" but is more like a constant attempt to keep a flawed car under control.

Jonathan
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Report this Post01-12-2014 06:42 PM Click Here to See the Profile for R RunnerClick Here to visit R Runner's HomePageClick Here to Email R RunnerSend a Private Message to R RunnerEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

I definately agree with the neutral handling setup goal. I don't know how or when having the rear come around would be beneficial. That to me is not a matter of "how you drive your car" but is more like a constant attempt to keep a flawed car under control.

Jonathan


Having the rear come around is not, however, having it a little loose can sometimes help you set the angle of the car through a turn with exit speed in mind. But in general, it is not desired.
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California Kid
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Report this Post01-12-2014 06:57 PM Click Here to See the Profile for California KidSend a Private Message to California KidEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by R Runner:


Having the rear come around is not, however, having it a little loose can sometimes help you set the angle of the car through a turn with exit speed in mind. But in general, it is not desired.




https://www.youtube.com/watch?v=mVsGgIq9dTA
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Report this Post01-13-2014 08:56 AM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
Torque steering the rear outward with a blip of the throttle is cool! Being able to do it because you have sufficient horsepower to overcome the traction of your good tires is even better.

Having it happen unexpectedly when going around a traffic circle in the rain simply because the suspension isn't set up for neutral handling, sucks!

Jonathan
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Report this Post01-13-2014 10:52 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by hyperv6:

If you want a Fiero to handle better just buy an 88 or pattern the changes and alignments after an 88. The Fiero is never going to be a C7 but you can still have a fun to drive car that is not a lot of work to keep on the road.


 
quote
Originally posted by R Runner:

My point is that many people talk about the bar diameter. True, it is very important, but a sway bar links each side of the suspension through torsion.



I just put new stock style rear struts on our 86 2m4, its going to need an alignment. It has a rear Addco bar, everything else is stock. It gets driven on joyrides, long cruises and to shows.
Recommend having it aligned to stock specs or something slightly different?

After reading this thread I may try and drive it hard sometime and decide if I want a stiffer front bar, or maybe just poly front bar bushings?

[This message has been edited by 2.5 (edited 01-13-2014).]

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Report this Post01-13-2014 12:40 PM Click Here to See the Profile for Formula88Send a Private Message to Formula88Edit/Delete MessageReply w/QuoteDirect Link to This Post
A sway bar isn't a box of handling you bolt onto a car. If the rest of the car isn't set up for it, it can make things worse.

Increasing front roll stiffness increases understeer.
Increasing rear roll stiffness increases oversteer.

Understeer is easier for the novice to control and safer. It's also slower.
Oversteer is harder to control, but in the hands of an expert it offers more control options and is faster with a skilled driver.
If your front end is sloppy and you put a new rear sway bar on, you're going to have a lot of induced oversteer.
You want as close to a neutral setup as you can get so the driver can induce either oversteer or understeer. Again, this isn't as easy to control as a car that understeers by design.

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Report this Post01-13-2014 06:11 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
Ok this whole deal is like replacing a old bad carburetor.

You can take a Holley out of the box bolt it on and odds are it will be a lot better in most cases. Now that is not to say it is not right.

If you tune and rejet a car for the set up you have it will run even better. Too many people are ok with better and never reach to where something is tuned right.

Same applies to a suspension as getting the cars balance front to rear right is important but also the correct dampening. Yet even more important is getting the alignment right and not to go out of spec. With the Fiero is a big issue and there are several things to address as all the good shocks, bars and tires will not cure it all.

Knowledge and testing is the only way to correct the issues unless someone has it sorted out and hands you a list of things to do and what adjustments to use.

If it were so cheap and easy GM would have gotten it right to start with. Just look at all the changes from 87-88. This is what they decided it needed and not just added some bars and shocks.
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Report this Post01-14-2014 01:37 AM Click Here to See the Profile for CarcenomyClick Here to visit Carcenomy's HomePageSend a Private Message to CarcenomyEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

I just checked the TFS website and they do not offer a front sway bar as a stand alone item. They do have one as part of a total suspension upgrade package. I think they have their marketing backwards. If they are going to offer either sway bars separately, it should be the front. To only add the rear is irresponsible since it overpowers the front stock bar.

Jonathan


http://www.fierostore.com/P...spx?s=57032&d=45&p=1

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Report this Post01-14-2014 09:39 AM Click Here to See the Profile for BoostdreamerClick Here to Email BoostdreamerSend a Private Message to BoostdreamerEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Carcenomy:


http://www.fierostore.com/P...spx?s=57032&d=45&p=1



My bad.

Jonathan
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Report this Post04-24-2014 04:40 PM Click Here to See the Profile for phantaztixSend a Private Message to phantaztixEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Boostdreamer:

I just checked the TFS website and they do not offer a front sway bar as a stand alone item. They do have one as part of a total suspension upgrade package. I think they have their marketing backwards. If they are going to offer either sway bars separately, it should be the front. To only add the rear is irresponsible since it overpowers the front stock bar.

Jonathan


They do have one:
1" Front Sway Bar
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Report this Post04-25-2014 06:09 PM Click Here to See the Profile for fierobugClick Here to Email fierobugSend a Private Message to fierobugEdit/Delete MessageReply w/QuoteDirect Link to This Post
Great thread everybody! Thanks for an informative talk on suspension and handling. I have alot to learn but it is starting to sink in. I'm going to take it out tomorrow (87gt auto) with new kyb front shocks, bushings, tie rod ends, ball joints and monroe sensatrac rear struts (need alot of work on rear) and do the R Runner test for fun. Front end is a world of difference like everyody said it would be. Can't wait to get new bushings. dog bone, motor mounts etc installed eventually on back end. Sometimes wonder why I am doing this and then I remember the price of real sport cars. Like said, need everything up to spec then will know where my rear is - so to say. Thanks again everybody!

------------------
FIEROBUG!!!!!!!!!!

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Dave E Bouy
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Report this Post04-25-2014 09:33 PM Click Here to See the Profile for Dave E BouyClick Here to Email Dave E BouySend a Private Message to Dave E BouyEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have head my 85 GT on the track at Watkins Glen a few times and it carves through turns like a go-kart. My suspension has been rebuilt with poly and just plain old sensatrac shocks. However, on one of those track days I hadn't put my rear sway back on after some winter work and I might as well have been in a snow plow. It was all I could do to keep up with the pace car which was a Toyota pickup truck.

DF
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Report this Post04-25-2014 11:45 PM Click Here to See the Profile for RavantSend a Private Message to RavantEdit/Delete MessageReply w/QuoteDirect Link to This Post
Mine right now is exactly so-so. Front strut seals are blown, but otherwise, it doesn't feel loose or otherwise scary to drive. I've driven much, much worse, more floaty examples of things that I'd never want to drive again, when compared to this poorly maintained '85 base coupe.

That said, she's due for an '88 rear swap, a West Shore Fabricating front sport suspension and a bunch of other new/tightening parts. I'm sure it was fine, stock, from the factory, but I am /very/ picky about handling in general. As-is? I wouldn't trust it to take me around a corner at 20, let alone some reasonable speed. Though, I've driven an '88-swapped '86 GT and honestly? I can't wait to finish this car now, only to see where it's going from here.
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Report this Post04-26-2014 01:54 AM Click Here to See the Profile for crashyoungClick Here to Email crashyoungSend a Private Message to crashyoungEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have driven 4 different Fieros over the years, and I have added a stock front bar to the rear
of two of my daily drivers. Two Fieros turned into parts cars, and the other is my wife’s car.
I would not drive a Fiero as hard as I do without a rear bar. Period. And I drive mine hard.

That being said, I also did the poly control arm bushings in the front and rear, as well as the
dog bone. I would recommend as a minimum. a rear bar, and ensuring the bushings and ball
joints are good. But the more you do, the better the handling will be. Learning how to drive it
is another matter, as it takes time and skill to drive a mid-engine car with good results. I learned
by 13 years driving summer AND winter with my first Fiero. The winter driving is where I learned
the most!

This is my experience, your results may vary, no warranties implied or offered...
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hyperv6
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Report this Post04-26-2014 08:50 AM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
I still think many here miss the real point.

It is not so much what you use but the relationship of what you use with each part of the car.

In other words you have to get the geometry right on what you use and the relationship of each parts effect on each other. R Runner was covering this pretty well.

The whole thing is you can slap on a bunch of parts but if they are not tuned to work with each other properly then you will not get the results you want. Also how many cars are worn out and adding parts like this are still not going to address the root issues of a worn out car to start with.

If you note in racing that teams will try many shock, bars and springs to find that right combination. They will also use computer simulations to check these even before going to the track. There is math and science to this and while some get lucky you really need to know what you are doing to be very effective here unless you have a sorted kit from someone.

In other words just adding a front bar to the rear or whacking some springs off will not always give you the proper to full results of what you can do. Suspension are a science of their own and too many think if I can bolt this on or change that I will always make it better. Well sometimes you might but too often you may help in one area and set the car back in another. The odds of refinement are slim.

Many need to read what R Runner said on refinement and balance as this is the key to better handling. Bigger is not always better and you have to do the work to find that right tune. This is no different than the biggest mistakes people make on cars. I see it daily where a guy buys a Holley 750 Double Pumper and wonders why his car smokes. The carb is way too big for his needs, why because he did not match it up to his engine. A smaller carb would have done a better job and run much better. Same on Cams and Compression where people go big and never match it to the needs of the car and use.

There are three kinds of people out there. Those who know what they are doing and are able to set up a car properly with the right math and technology.

There are parts changers that tend to think they have it covered because they can bolt on parts but never reach the point of knowing what the true results will be. [We all start at this point but many never progress past with better information and education.]

Then there is the guy who knows his limitations and looks for fully sorted kits that someone else who knows what they are doing put together.

I was lucky to see one of the early FIero's GM used for suspension testing back in 83. The car was in a museum where it still had the notes and the bars in the trunk. GM had a bunch of rear bars they were playing with and working on before they got the plug pulled on no rear bar. This tells us even the big boys with all the test equipment and knowledge in the world still have to do their home work and testing to see just really what is best.

The combination of parts and not the sum of all parts is how this works. You need to get the car to work as one front to rear or you will be basically driving two different cars that want to steer and grip different front to rear.
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Report this Post04-26-2014 09:15 AM Click Here to See the Profile for olejoedadClick Here to Email olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
/\ /\ /\

True words. Thank you.
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Report this Post04-26-2014 11:36 AM Click Here to See the Profile for sspeedstreetClick Here to Email sspeedstreetSend a Private Message to sspeedstreetEdit/Delete MessageReply w/QuoteDirect Link to This Post
This is what a 1988 looks like "at the limit" at high speed.

https://www.youtube.com/watch?v=RqBfEbYIXm8

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