1986 SE w/ 2.8 and auto trans. I chopped one coil off the front springs and added new shocks. In the rear I chopped the perches off the new monroe rear struts and added Summit Racing sleeves and 12" long 275# coil over springs. I set the rear to be level with the front and had a 4 wheel alignment. I'm running new 16" 205/55-16 tires. Also about a rear ago I replaced all the ball joints and tie-end rods. I'm starting to get a lot of wheel hop out of the rear when I go around tight curves like a on/off ramp. Half my drive to work is interstate. When I fly around a sharp 90 degree turn on normal roads it handles great but when I try and zoom around a clooverleaf style on/ off ramp the back end starts bouncing up and down. The car doesn't have a rear sway bar. Anyone else had this issue and if so what is the solution? Thanks!
It's in the drivetrain geometry. As you accelerate in a curve, the inside tire can be the 'drive wheel' until it slips...and then the outside tire is the 'drive wheel'....but then the inside tire grabs again and over and over.... the dis-similar axles don't help....the rear sway bar does help, but I can make it happen in my Formula too.
Remember, the Fiero is a commuter car!...not a sports car, according to GM, so SLOW DOWN is good advice. At that point you must be going faster than all of the cars around you, because the Fiero is very good at that sort of thing.
Rear sway bar makes it feel like a totally different car! It's amazing the difference it makes. How fast are you taking those ramps just out of curiosity?
Around 45mph plus is where the wheel hop starts getting to be a pain. I was looking and there is place that has the ADDCO 387 rear sway bar for $150.00. Is the Addco a good choice? The bushing may be at fault too. When I had the alignment they noticed all the new parts I added but didn't say anything about any bushings being worn. Usually those are the type of things from my experience they try to make some money off of you on.
You're probably over-driving your tires and suspension. A sway bar might help a little bit, but won't be a "silver bullet". You'll also need wider rear tires, stiffer cradle and suspension bushings, etc.
Yeah definitely fix anything that's worn first, including worn out cradle bushings. (I added a sway bar to my 85 before changing out any bushings and it made it pretty scary at highway speeds, no need in tying loose components together) but with all suspension parts in good condition it will handle like it's on rails. Everything is fresh on my car and I don't have enough guts to find its limit in a cloverleaf, but I've taken them at 50ish no problem.
I would say that the struts are the problem. Monroe sturs are not designed to be worn with lowering springs of any nature. They force the strut to wear in key points without full articulation.
They will fail quickly and what is happening to you is from a worn out strut.
Monroe sturs are not designed to be worn with lowering springs of any nature. They force the strut to wear in key points without full articulation.
They will fail quickly and what is happening to you is from a worn out strut.
I've had Monroe Sensa-Tracs on my '84 for the last four years with two coils cut off the front and rear springs. It's been a daily driver and autocrossed about 25 times over that time span.
My Sensa-Trac shocks and struts work just fine. Do I have a freak set of good ones?
[This message has been edited by Patrick (edited 12-27-2013).]
I would say that the struts are the problem. Monroe sturs are not designed to be worn with lowering springs of any nature. They force the strut to wear in key points without full articulation.
They will fail quickly and what is happening to you is from a worn out strut.
Looks like there are many things I need to inspect again. I did use the basic Monroe struts and when I was replaing all the ball joints, rear wheel bearings, brake calipers, pads and rotors. The cradle bushings and lower A-frame bushing seeem to be in good shape at that time. All of that was a year ago and I do like to have fun in my Fiero. I have thought about wider tires in the rear but when I added the tires and rims I still had the factory springs on them and had to add spacers to keep the tire and rims from rubbing the lower spring perch on the strut in the rear. Now that the perches are gone I can look into wider rear tires. When you add the rear sway bar how much ground clearance do you loose? I need to drop the fuel tank soon and try to either get the original sending unit working or swap it with an aftermarket one. A friend of mine recently installed a car lift in his machine shop. Hopefully he will let me use it to drop my tank and at that time I can go thru the rear suspension. Thanks for all the advise.
The Addco rear sway bar reduced ground clearance on my '87 Fiero by about 1.5". The car had about 4" of ground clearance, not counting the sway bar. But the center of the sway bar was only about 2.5" off the ground. I had to be REALLY careful not to get the sway bar hung up on obstacles. If I had it to do over again, I'd look for a sway bar that doesn't hang down from the bottom of the engine cradle.
I think the "front sway bar on the back" mod allows you to tuck the sway bar up out of the way. And the racing sway bars from HHP are tucked up out of the way, too.
When you add the rear sway bar how much ground clearance do you loose?
Not much. You can see with the way I've mounted a front sway bar in the rear of my '84 that I perhaps lost an inch and a half of clearance.
quote
Originally posted by Patrick:
I autocross my '84, and yes, it's totally "worth it" to install a rear sway bar.
This will give you a bit of an idea of how it's mounted. You can install the sway bar with the arms pointing forward or towards the rear. I chose the latter method, and I'm very happy with the result.
It's a Fiero front sway bar, probably from an '86.
If I remember correctly, '84 Fieros (which I installed this on) have a slightly thicker front sway bar than the '85-'87 Fieros, and I wanted the added bar on the rear to be a little weaker than the factory bar on the front.
Whatever it was that I did, it make a helluva difference with handling on the autocross track. With good tires, the car will now actually turn in the direction that I'm pointing the wheels.
Information is available for free on the Internet. It's awesome that people have had good luck with factory replacement struts and lowering springs. I have been one of the many that have not. Altering spring rates, and heights on struts that are engineered For a specific stock vehicle is like using a strut from a different application and expecting it to last just as long. It doesn't.
I've had the exact problem as above happen to me before. The issue was resolved with the struts being replaced. He said it was taking a turn at 45 mph where it's very noticeable. Check the sides of your struts to see if they are leaking oil.
Best of luck to the O.P. Be sure to post results.
[This message has been edited by Custom2M4 (edited 12-29-2013).]
Information is available for free on the Internet. It's awesome that people have hadu good luck with factory replacement struts and lowering springs. I have been one of the many that have not. Altering spring rates, and heights on struts that are engineered For a specific stock vehicle is like using a strut from a different application and expecting it to last just as long. It doesn't.
I've had the exact problem as above happen to me before. The issue was resolved with the struts being replaced. He said it was taking a turn at 45 mph where it's very noticeable. Check the sides of your struts to see if they are leaking oil.
Best of luck to the O.P. Be sure to post results.
One coil off of the rear spring will only move the center of duty cycle 3/4", and increase spring rate about 10%.
There is a lot of bad info on the net. Your first post was bad info.
Yeah, it works very well... and it was inexpensive!
If you want to see some more info on how I did this, have a look at both pages HERE.
Read your write up. Pretty cool. That explains the steel plate in your assembly. I am assuming the existing hole in the rear lower a frames is used? Just opened up for the end link bolt. So the front sway bay is the correct width?
And to the other guys post reffering to chopping springs. I cut the front springs not the rear. I added 12" coil-overs on the rear. Over the weekend I looked the struts over and they are not leaking. I did add some more rubber to the tops of the coil overs. What I added a year ago had broken down some. It was snowing this morning on my way to work and everyone was driving extra slow. I had to putt thru all of the curves.
Thanks for the clarification, I mis-read your post. The 275# coil-overs may not be fully damped by the Monroes. I would still look at rear control arm bushings.
So you're thinking a better strut would help with the dampening? What do you reccomend? I will try and get a better look at the bushing this coming weekend. I'd like to get it up on my friends lift to do a proper inspection.
One coil off of the rear spring will only move the center of duty cycle 3/4", and increase spring rate about 10%.
There is a lot of bad info on the net. Your first post was bad info.
So is this post.
If you have 5 active coils and you cut one off, the rate increase is substantially more than 10%.
Moving where the strut rides by less than an inch probably isn't a problem on its own, however, since you've raised the spring rates by 20-25% and haven't changed the struts, you ARE MEASURABLY UNDERDAMPED. That's especially the case if you start with cheap parts-store struts that are arguably not up to the task of controlling vehicle motion at the stock spring rates. Its unfortunate that actual performance strut options for the Fiero are few, since the commonly available Monroe / Gabriel / etc are wholly insufficient for performance use.
I think there is still some confusion here. I chopped the front springs and totally replaced the rear springs with Summit 12" long 275# coil over springs. I figured none of the local auto parts stores Monroe or Gabriel structs would be recommened. That is what I am using now. I was figuring something like KYB or the other more racing struts would be recommended.
The kyb gr2's are still a stock replacement, but more of a higher quality replacement. If you want a strut to last the life of your car, given the coil overs and aggressive driving, go with a koni strut. I prefer not to change parts because I cheaped out, almost as much as being called an idiot when someone didn't read the first post.
Edit: what kind of padding are you putting on your springs, and where? You don't really need much of a cushion, just to keep the noise and spring movement to a minimum...
[This message has been edited by Custom2M4 (edited 12-30-2013).]
As far as the padding for the top of the springs I am using rubber gasket material. I just cut a 2" hole in the middle and slipped it over the top of the springs. Nothing fancy. I will look for Koni struts and see if they are in my price range. If not maybe I will go with a higher end OEM strut. When I bought the base Monroe struts I was still running the stock springs. After reading some post here about adding coil overs I got the bug and bought the springs and sleeves from Summit.
For what it's worth, my KYB struts are doing just fine with 350 lb/in coilover springs. I still think you need a rear sway bar and wider tires, though.
I am assuming the existing hole in the rear lower a frames is used? Just opened up for the end link bolt. So the front sway bay is the correct width?
Yes, the front sway bar is the correct width, and with the way I mounted the bar there are existing holes in the rear lower control arms which line up perfectly for the end links.
