quote Originally posted by mender: It doesn't matter in the slightest; when one end of the bar is trying to go up, the other is trying to go down. Whatever way fits the best (no bind, no contact) is the right way.

I understand the action of the sway bar is just the opposite. In hard cornering, say to the right, the left side suspension is compressed, causing the car to lean to the left. At the same time, the right side suspension is being unloaded and pushing that side of the car upward.

The left end of the sway bar is being pushed upward through the end link. That motion is in part, transferred to the right side suspension, pulling it upward, helping to keep the car more level. There is a degree of twist in the bar, but the two ends don't work in opposite directions. That's why a bigger and stiffer sway bar decreases roll.

The sway bar is also known as a stabilizer bar. It keeps the suspension of the two sides pretty much equalized when going in a straight line. You never want to be in a car at any speed when the sway/stabilizer bar malfunctions. In my teen years, I had a 53 Buick Special two door hardtop. I was riding along in my automobile, my baby beside me at the wheel. One arm around her when all of a sudden the car started to wallow badly. I almost rolled it over. Lucky there were no other cars around because it took the whole two lanes to keep it under control and get stopped. When I got home, I found that the sway bar had snapped in the center. An angular break that had been in progress for some time, judging by the rust. Apparently a flaw in manufacture.

I'm like you, mender. When my gut tells me something, I've got to do something about it. Very quickly.

[This message has been edited by fierofool (edited 04-19-2016).]

I put it in terms of car reaction like I do for some of my drivers but you are correct, the bar resists twisting force. When the left side of the car is trying to go down (right turn), the right side of the car is trying to go up and the bar resists that.

I do suspension mods and tuning for a living, was a NASCAR crew chief for five years and have been reading everything available for the last thirty years. To quote Boston, it's "more than a feeling", it's science!

The most correct term is anti-roll bar.

[This message has been edited by mender (edited 04-19-2016).]

quote Originally posted by mender: To quote Boston, it's "more than a feeling"...

A 70's classic... love That song.

Picked up the spacer plates today and got them installed.

****NOTE: THESE SPACERS WERE DISCARDED AND NEW ONES DESIGNED THAT WILL BE WELDED TO THE CRADLE****

The spacers alongside the bushing bracket.


With the spacer in place, you can see the clearance on the right side


Left side


And center underneath the crossmember.


Along with the bigger sway bar that was already on the front, I can say that it absolutely stiffens the suspension. When I jacked it up to remove the jack stands, I placed the floor jack underneath each sway bar bushing. Lifting the driver's side first and removing the stand. When I let it down, the wheel didn't touch the ground. When I originally lifted the car underneath the cross member, both rear wheels were only slightly off the ground when I placed the stands. After the bar was hooked up, there was about 3-4 inches space between the tire and ground.

I took it out for a very cautious drive through curves that I normally hit pretty hard in the 87. I can say that even at 45mph, I could tell a difference. There was definitely a reduction in understeer. The car turned very easily into the curves. It actually feels like it may have created some oversteer because the rear seems to come around much easier. I don't know if it's just my perception, but for the time being, I'm planning to be pretty cautious until I get a good feel of how it will react on a hard turn. Off to a vacant shopping center parking lot this weekend to see what it takes to make the rear come around on me.

[This message has been edited by fierofool (edited 06-12-2016).]

quote Originally posted by fierofool: It actually feels like it may have created some oversteer because the rear seems to come around much easier.

And that's why I stuck with all rubber bushings in the back (to lessen the effect).

You may find it's okay when you get used to it... but in the meantime be careful.

I used the poly because the existing holes were too far apart for stock bushings. This is planned to be a temporary setup. The final product will have threaded studs spaced to accept stock bushings and won't be slotted. The ProThane bushing mounts are slotted, so they will also mount on the same studs. People will then be able to better fine tune their car like you did, or just save some cash by using their old mounts.

Another adjustment I will make is to turn the bar over. I only used the 4 washers to substitute for the sleeve and once the suspension was loaded, the paddles turn up slightly. I don't want to go to a longer bolt because of the 40 series tires. When I install the second generation plates, they will be welded to the frame rather than bolted.

quote Originally posted by fierofool: I used the poly because the existing holes were too far apart for stock bushings.

Charlie, just for clarification, I was also referring to the end-link bushings.

I had to run some errands for the wife so I took it out for another test drive. Took a 90 degree right at an intersection and it did very well. I traveled about 100 yards, enough to regain my speed, and took a hard left, both in 3rd gear. The rear really wanted to come around on the left turn.

On the way back, there were two vacant shopping centers. I got up some speed and took a hard left. Again, the rear came around. Traveling back to the other end of the lot, I took a hard right without the rear trying to come around. Same thing happened at the second shopping center. It comes around on a hard left, but not on the right. I'll need to get back under it and see what the difference is between the two sides. The full suspension bushings, shocks, and struts, ball joints and tie rod ends have been replaced, so I don't think it's anything loose or worn. I may remove the rear bar and give it a try without it. I've never had it in the twisties since the rear bushings and struts were replaced.

Find as flat a spot as you can for this.

Disconnect both ends of the bar and bounce the car a few times to get any pre-load out of the suspension. Attach one side with the rubbers just snug, not squashed, and see how close the other side is to fitting the same way. If the other side is very close, install it and tighten both sides the same number of turns. If you need to, use the appropriate sized washers to equalize the end link lengths.

One thing to be aware of is to have exactly the same amount of throttle on as you test the cornering balance. Lifting mid-corner will shift the balance noticably towards oversteer (inducing trailing throttle oversteer). Proper testing will be more than just a quick swerve either way; you should have enough room to let the car take a set before judging what the handling balance is.

[This message has been edited by mender (edited 04-21-2016).]

When I tightened the end links, I did take the same number of rounds on each nut. On my test drive yesterday I drove about 4 miles. Today I put about 10 on it before the sharp right and left. I then did probably 6 miles before the first shopping center then another 8 before the second. I did have the suspension unloaded when I tightened the end links. I'll check that.

Tuning the sway bar like a torsion bar.information I learned from years of racing. I like Rodney dickmans endlinks, front and rear. Nice read.

I've pulled the bar off the car. After driving it about 150 miles under normal highway conditions I found 1 bushing mount bolt on each side was stripping out of the cradle. Apparently the threads in the cradle were already weak or I used the wrong bolt thread. The latter is most likely for the car was put very heavy paces with the original install that Aerodonamic did.

Anyway, it gave me good reason to proceed with Design Stage 2 for the spacer plates. The new plates will allow mounting a stock 84-87 front sway bar on the rear of pre-88 Fieros in either the forward or rearward position. Thw mountung plates eliminate clearance problems with control arm bushings and exhaust pipe when the exhaust is properly installed and supported. No drilling into the cradle or control arms except for the rear position one would need to drill the extra holes in the control arm for the end links. They will accept both stock GM rubber mounts and other aftermarket poly mounts like the ProThane sold by The Fiero Store.

Whether a front cradle or rear cradle setup, about 10 minutes welding is required.

Let me know if you may be interested. Machine shop price for my set is $60. He said an order for 3 sets would bring them down to $40-45 a pair.

He will start on my set on Monday morning. If anyone wants in on a group buy, let me know by 10 AM Monday. I will get a unit price for the quantity , notify each person and accept PayPal in advance. I can't afford to have a batch made without a financial commitment which will be refunded if you return them in original condition. Shipping isn't included in the unit price.

I'm not a scammer, there will be no string of delays or excuses. I have a very solid reputation in the Fiero Community as a buyer and seller. You should have your parts by May 7.

Design Stage 2 looks nothing like the first design above.

[This message has been edited by fierofool (edited 04-29-2016).]

"Taking a set" means a long steady corner at the traction limit. That gives the suspension time to display the mid-corner handling balance (spring and sway bar balance) rather than a quick transition which is more about the shock rates.

Eg, if you have very high rate front shocks and high rate rear springs/sway bar, a sudden swerve will first display understeer because of the shocks then oversteer because of the rear springs/sway bar after the chassis settles down.

[This message has been edited by mender (edited 04-30-2016).]

Nothing special with the front or rear shocks and struts. Just fresh stock Monroes front and rear. I did notice that once the bar was installed on the rear, it seemed to ride stiffer back there. Removing it softened the rear bounce.

Road Atlanta Skid Pad is about the only place I could keep up a steady turn while increasing speed, but I don't have any inside contacts any more. I have to be cautious about the shopping center ventures due to heavy police activity in both areas.

After a little hiatus, It's finally coming together. New mounting pads were designed and made, following Patrick's lead.

So here goes:

MOUNTING A STOCK 84 THRU 87 SWAY BAR ON THE REAR OF AN 84 THRU 87 FIERO
FOR CORRECT POSITIONING, THE CAR SHOULD BE BACKED ONTO RAMPS OR ON A WHEEL LIFT RACK. THE SUSPENSION SHOULD BE LOADED AS IF BEING DRIVEN ON A LEVEL SURFACE.

The mounts are designed to be used for a front or rear cradle mount, utilizing the stock front 84-87 sway bar. When mounted to the front of the cradle you can use the rearmost factory holes in the rear control arms. If you mount the bar on the rear of the cradle, you must drill holes in each control arm. The pads give added clearance to the exhaust system and bring the bar ends more parallel to the control arm, give a stronger attachment than bolting into the cradle and eliminates bolt interference with control arm bushings.


Before beginning, look at your sway bar. You will see that one end is rounded while the other end is either pointed or has a flat edge. This is the driver’s side as was originally mounted on the front of the car. Using my combination of bolts and washers for spacers, the pointed or flat end should be to the passenger side if you are mounting to the front of the cradle as in my illustrations.

To start the process, I used the factory sway bar bushings and their housing. The reason I did this is because they aren’t slotted. It will position the mounting pads so that either aftermarket poly or stock bushings may be used. Some say they have found the poly to be a little too stiff, creating oversteer, or too noisy and went back to the stock rubber bushings and housing. Because poly housings are slotted, it’s possible to weld the pad to the cradle in a position that doesn’t allow proper alignment should one want to return to rubber mounts. I only tightened the nuts on the mounting pad studs enough to still allow rotation and some side to side slip on the sway bar. This allowed fine tuning of the pad to the cradle.


To be sure that I had the bushings as much on the straight portion of the bar as possible, I positioned the studs inboard, leaving the larger portion of the mounting pad to the outboard side. You might want to do a trial fit with the studs to the outboard side if you decide to do a rear of the cradle mount. There’s ample room to do it at the rear because the rear of the cradle is spaced closer together than the front and the bushings would probably still be on the straight portion of the bar.

Using GM recommendations for installing front end links, I tightened the nut, compressing the bushings, until the nut fully bottomed out on the last thread of the bolt. That pretty much took out all front to rear and side to side movement of the bar.

I then raised the bar with the floor jack, just to the point that the pads came into contact with the cradle and began to level out against the cradle. I could still slide the bushings and pad side to side to align it with the cradle.


Be aware that you need to put the outer edge of the pad flush with the outboard edge of the cradle. This is especially true on the passenger side, giving clearance for access to the nut for the front motor mount. It also leaves room for full access to the control arm bushings on either side.


Once everything was satisfactory, determined that the end paddles were horizontal to the control arms, the end links were as vertical as possible, the pads were welded into place. Now, I will remove the stock swaybar bushings, install the poly bushings and evaluate the handling. If I find them unsatisfactory, I can go back to a softer factory bushing.

[This message has been edited by fierofool (edited 06-12-2016).]

Looks like it's coming together.. congrats!

Just to share but there are (or were) two different size rear sway bars available. There was the Fiero Store design and the Adcco design. The Adcco bar was heavier , a large dia .IIRC. When I used the Fiero Store bar (similar to the old Herb Adams bar) it worked well as is. When I installed the rear Adcco sway bar strong oversteer resulted. I then had to install the matching Adcco front bar to balance things out. In either case the difference in handling was dramatic and the bump steer seemed to disappear. I would say that installing a rear sway bar or the Adcco set brings the handling of the 84-87 Fieros very close to the handling of the 88

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

A previous owner installed the Fiero Store or Addco bar on the front. It's a much larger bar than stock. This combination had been on the car for years and the two previous owners were very happy with the performance.

If this setup doesn't outperform my stock 87, well at least I have a stock front bar I can move back to the front. At that time, there will be a heavy duty front sway bar for sale in The Mall.

quote Originally posted by fierofool: A previous owner installed the Fiero Store or Addco bar on the front. It's a much larger bar than stock. This combination had been on the car for years and the two previous owners were very happy with the performance.

IMO, with no added rear sway bar, that heavy bar in the front would've resulted in the inherent factory understeer being worse. Installing a rear sway bar has to help I would think.

In regards to the potential of the rear end snapping around, I think it needs to be made absolutely clear that even a properly balanced suspension (with the addition of a rear sway bar) will still bite you if the brakes are applied and/or if the throttle is suddenly released while in the midst of a fast turn. For me, participating in autocross has been invaluable in regards to drumming into my brain not to do that!

If you can get on a skid pad and drive around and around in a tight circle while slowly accelerating, and the rear end of your Fiero doesn't decide to pass you (and conversely, the front end doesn't plow), then your rear sway bar set up is fine. My '84 (with the added rear sway bar) will actually four-wheel drift sideways if/when I lose traction... and it feels under control while doing so.

[This message has been edited by Patrick (edited 06-13-2016).]

quote Originally posted by Patrick: In case there's some confusion, I want to make it absolutely clear that the spacers had nothing to do with the end-links. From my link posted above... [QUOTE] The only thing that would've made the job easier would've been if the spacers weren't required for the sway bar mounting brackets, but the holes for them would've required drilling up through the cradle into the control arm bushings. That obviously wouldn't have worked, so using the spacers allowed us to spread the bracket mounting holes further apart, thus avoiding the control arm bushings. (The spacers also allow for more clearance between the sway bar and the exhaust pipe on systems that may require it.)

[/QUOTE]

ag9123, you quoted me from Here. Did you have a question?

This morning I got the plates welded to the frame. I managed to get all 4 sides to keep water from getting between the spacer and the cradle. I used a little flux core wire feed to do the job. Pardon the bead. It's been just over 16 years since I've welded.



In my initial test drive on some local rural roads, just swishing it back and forth, left to right, the reaction in both directions seems to be equal, so the left turn oversteer I was experiencing is gone. It's still very stable at 45-50 mph during regular driving. In the next two weeks, I'll gradually work up to more and more aggressive maneuvers only to the point that I begin to feel safely uncomfortable with it.

[This message has been edited by fierofool (edited 06-14-2016).]

quote Originally posted by Dennis LaGrua: Just to share but there are (or were) two different size rear sway bars available. There was the Fiero Store design and the Adcco design. The Adcco bar was heavier , a large dia .IIRC. When I used the Fiero Store bar (similar to the old Herb Adams bar) it worked well as is. When I installed the rear Adcco sway bar strong oversteer resulted. I then had to install the matching Adcco front bar to balance things out.

My experience was similar. When I installed the Addco 3/4" rear bar on my Fiero (with the stock Fiero bar still in front), the oversteer was a bit too much. I found that putting rubber bushings on the back and urethane on the front bar brought the oversteer down to tolerable levels.

With my current set up, I have urethane bushings and end links on the front and rear, urethane control arm bushings on the rear, but I'm not sure what's been installed on the front. The front is awfully squeaky when maneuvering into or out of parking spaces and the driveway, is all I know. Always has been.

In my little test drive yesterday the car does turn more easily and doesn't require nearly the effort, even on a straight road. I don't know if that's leaning toward oversteer or just reducing the understeer.

Until the car is pushed to the limit of traction, you won't know if it's under or over steering.
The addition of a rear bar will make the car more responsive feeling, as the roll characteristics have been changed.

A damp parking lot is your friend - you can learn a lot about your changes at relatively slow speeds.....

quote Originally posted by fierofool: The front is awfully squeaky when maneuvering into or out of parking spaces and the driveway, is all I know. Always has been.

Probably poly then.

I'm in the process of installing a stock front sway bar on the back of my 84.
Was hoping to use the original holes in the lower control arm to mount the links but
when I line the bar up to drill the mount holes in the cradle, it looks like the control arm mount is right in the way.
Any suggestions for working around this?
Drill new holes in control arms to move the links forward about an inch?
Drill the cradle holes so they don't interfere with the control arm bolt?

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1984 Indy Fiero

You can do as Patrick did and use a plate large enough to spread the bolts beyond the bushing area or I will sell you my extra set that you can weld onto the cradle.

If you plan to mount to the rear of the cradle you will have to drill new holes in the control arms. Go back to page 1 and look at the 4th pic I posted and you will see the center hole you will need to drill for a rear cradle mount. Bushings are a problem there if drilling into the cradle, too.

[This message has been edited by fierofool (edited 06-15-2016).]

Thanks for the quick reply! I'll drill some new holes in the control arms and get that bar mounted up

You can do as Patrick did and use a plate large enough to spread the bolts beyond the bushing area or I will sell you my extra set that you can weld onto the cradle.

If you plan to mount to the rear of the cradle you will have to drill new holes in the control arms.

ag9123, if you haven't mounted your sway bar, yet, I have another set of plates you can weld on.


The car drives like it has power steering. It's very easy turning into curves with just 1 hand but I feel more comfortable with 2 hands because of what I feel is oversteer. This sensation wasn't there before installing the sway bar at the rear nor the front of the cradle, so one conclusion is that a rear bar does reduce the inherant Fiero understeer tendancies.

In both front and rear cradle installs, I tightened the end link nuts until they bottomed on the shoulder of the bolt. About 2 inches worth of thread. I believe this made the rear too tight because the poly bushings were partially crushed.

This morning I backed off 3 turns on each rear end link nut. I just did a test drive and the adjustment is noticeable. Though there's still some feeling of oversteer, it's much less than before the adjustment. Once adjusted to the point total decompression of the bushings occurs, I will probably start playing with rubber bushings to develop a feel I'm satisfied with.

In both front and rear cradle installs, I tightened the end link nuts until they bottomed on the shoulder of the bolt. About 2 inches worth of thread. I believe this made the rear too tight because the poly bushings were partially crushed.

This morning I backed off 3 turns on each rear end link nut. I just did a test drive and the adjustment is noticeable. Though there's still some feeling of oversteer, it's much less than before the adjustment.

Once decompression of the bushings occurs, I will probably start playing with rubber bushings to develop a feel I'm satisfied with.

[This message has been edited by fierofool (edited 06-23-2016).]

Charlie, it seems you're experiencing exactly what I was earlier warning about. There are two ways to lessen the "oversteer" with this added rear sway bar... tighten the front and/or loosen the back.

quote Originally posted by Patrick Here: Keep in mind though that most, not all, but most Fiero enthusiasts say to keep the front suspension stiffer than the back... otherwise instead of balancing out the suspension (getting rid of the built-in understeer), unwanted oversteer becomes more of an issue. Therefore, on the front sway bar I've used poly bushings and zero-lash end links, whereas on the back I've used all rubber.

IMO, you should get rid of the poly rear sway bar bushings and the poly end link bushings and replace them with rubber. And make sure the front has been stiffened up in the manner I mentioned above.

Yes, my next step was to check to see if the front bolts and spacers were stock specs and how tight they were. I'm giving the current setup and adjustments a trial run on Saturday as we head to the mountains of North Georgia for our monthly meet and greet. It will bbe a very cautious trial run, though.

It just occurred to me that I have a friend, former head of Atlanta Regional SCCA, who raced an 86SE. Think I'll give him a call to see what setup he used. I want to have this one ready for this year's RFTH in September.

[This message has been edited by fierofool (edited 06-23-2016).]

quote Originally posted by fierofool: Yes, my next step was to check to see if the front bolts and spacers were stock specs and how tight they were.

I'm not 100% sure what you mean there... but just to clarify, nowhere was I referring to how "tight" any "bolts" were.

I would expect that Aerodonamic used the stock end link bolts and spacers when he installed the bigger sway bar and poly bushings for the owner. That's what they look like, lengthwise. GM recommends tightening down the nuts on the end link bolt until it bottoms out. This would put maximum compression on the end link bushings. Much more resistance than one would experience with factory rubber bushings. So, add that extra resistance to the resistance of a bigger front sway bar and you've stiffened a whole bunch. Loosening the front end link nuts may bring more oversteer, and if they can be tightened more, it should reduce it. Softer front, stiffer rear equals oversteer. Stiffer front, softer rear equals understeer is my theory.

quote Originally posted by fierofool: Loosening the front end link nuts may bring more oversteer, and if they can be tightened more, it should reduce it. Softer front, stiffer rear equals oversteer. Stiffer front, softer rear equals understeer is my theory.

I'm definitely not an expert... but IMO, the material the end link bushings are made from makes a whole lot more difference in handling than how tight the end link bolts/nuts are (after initially being snugged up). Rubber is soft, poly is considerably harder, and zero-lash end links have no give at all.

And of course the end-link bushings are totally separate components than the sway bar bushings which also come in rubber or poly.

[This message has been edited by Patrick (edited 06-24-2016).]

I have tried to get the car to push or tires to make noise. My sway bar is stock in the front (1") and (7/8") in the rear facing the front. All end links are Rodney dickmans endlinks. Car handles well with no bumsteer twitch. 2 yrs ago at new smyrna speed way I was able to push it.I am mainly in the 5 min YouTube video.maroune/ gray rims.by the end of 5 laps I passed the pace car. Set up is everything, stock springs with kyb shocks and struts

After reading this post and many others, it seems that it really comes down to personal setup/preference and trial and error.
It doesn't hurt to try different combinations until you find what works best.
I have the Rodney solid links in the front with poly bushings and all poly in back with a stock front bar.

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1984 Indy Fiero

Saturday I headed out to our monthly cruise in, which was in the North Georgia mountains, this month. I planned to take the shortest but most indirect route. Indirect being the crookedest roads. Due to a combination of issues, I never made it to the cruise-in, the most major being some family health issues.

Less than a half miles into the first hard curves, running at the posted speed limit of 45mph, the rear was extremely unstable. Rear tires screaming. Then at about a mile it started to overheat. My cooling fan motor stopped working, so I pulled off to let it cool. Got a call from my sister about our mother and had to return. The car setup isn't suitable for much more than the speed limit in any curve, and maybe not even that in some of the sharper ones.

Next step is to begin to soften the rear. The final solution will be to remove the larger front bar and the stock rear bar and move it to the front, putting the suspension back to stock. I can handle that. The front bar will then be up for sale. Probably cheap.

quote Originally posted by fierofool: Then at about a mile it started to overheat. My cooling fan motor stopped working, so I pulled off to let it cool.

The engine started to overheat while you were moving?

As far as I'm aware, the rad fan is only required if you're sitting still in traffic. Once you're actually moving (forward), the fan is redundant and unnecessary. I suspect there's something not quite right with the cooling system.

Sorry to hear you're having various issues with the car in addition to family health concerns.