1) The '88 cradle hard mounts to the frame rather than using the rubber isolation bushings employed in previous years.
2) The '88 rear suspension is a totally different design, so the suspension attach points on the cradle are completely different.
The only reason to swap an '88 cradle into an earlier year Fiero is for the '88's superior rear suspension. And you can't just swap cradles and suspension links and be done with it. You also have to modify the upper strut attach points.
[This message has been edited by Marvin McInnis (edited 10-23-2012).]
The main reason people swap the cradles is to utilize the tri-link independent rear suspension only on 1988 Fieros. I'm guessing you've either never seen and/or owned an '88 Fiero, but the setup in the rear of the car is DRASTICALLY different and improved over prior year Fieros. Instead of what is basically an a-arm front end setup shoved to the rear of the car, the '88 uses a tri-link bar setup to hold the rear hub assemblies in place. The tri-link allows for more points of articulation along the suspension lines. In addition, 1988 GT and 1988 Formula models received a rear anti-roll bar OEM.
There are aftermarket suspension setups for the 1984-1987 Fiero out there that get close to the 1988 setup, but they are VERY expensive to acquire.
The other major point like Marvin posted above is the hard mounting of the cradle to the space frame. GM realized by 1988 that worn cradle bushings were a problem, since it would eventually cause the entire cradle assembly itself to move under load transfer. They then simply designed the 1988 cradle to "hard mount" itself directly to the space frame. There are products out there - like Rodney Dickman's rear cradle bushings - that allow individuals to create a similar setup using a 1984-1987 cradle (basically, it eliminates all rubber in the cradle attachment points).
I'm guessing you've either never seen and/or owned an '88 Fiero, but the setup in the rear of the car is DRASTICALLY different and improved over prior year Fieros. Instead of what is basically an a-arm front end setup shoved to the rear of the car, the '88 uses a tri-link bar setup to hold the rear hub assemblies in place. The tri-link allows for more points of articulation along the suspension lines. In addition, 1988 GT and 1988 Formula models received a rear anti-roll bar OEM.
no i have never seen one does anyone have a picture of the differences?
There are aftermarket suspension setups for the 1984-1987 Fiero out there that get close to the 1988 setup, but they are VERY expensive to acquire.
quote
The other major point like Marvin posted above is the hard mounting of the cradle to the space frame. GM realized by 1988 that worn cradle bushings were a problem, since it would eventually cause the entire cradle assembly itself to move under load transfer. They then simply designed the 1988 cradle to "hard mount" itself directly to the space frame. There are products out there - like Rodney Dickman's rear cradle bushings - that allow individuals to create a similar setup using a 1984-1987 cradle (basically, it eliminates all rubber in the cradle attachment points).
so if i mount a sway bar and solid cradle bushings is it as good as the 88 cradle? or still no.
im trying to keep the handling better then stock so should i upgrade what i have or search for a 88 cradle?
im planning on putting a high hp 3800 in
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08:50 PM
Boostdreamer Member
Posts: 7175 From: Kingsport, Tennessee USA Registered: Jun 2007
------------------ Jonathan 23K mile '85 notchie - Still under construction https://www.fiero.nl/forum/Forum2/HTML/121056.html I'm not a mechanic but I play one in my garage - me Power tends to corrupt, and absolute power corrupts absolutely - Lord Acton Those who hammer their guns into plows will plow for those who do not - Thomas Jefferson The tree of liberty must be refreshed from time to time, with the blood of patriots and tyrants - Thomas Jefferson
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08:52 PM
FieroCustom Member
Posts: 294 From: Kent, WA, USA Registered: Nov 2004
The 88's handle like they're on rails! I have a very hard time going back to a pre-1988 now.
------------------ John 1955 Chevrolet 210 Sedan (Shopping list in progress) 1988 SE seized duke...next engine...1996 LQ1 found ~Future 1990 Fiero Clone? 1988 T-Top Coupe rocking 41 MPG! 1986 SE Project Mayhem 1999 F350 Crew Dually ~17mpg city 22 hwy Wife's 2001 Saturn SL1 51MPG high score
The 88's handle like they're on rails! I have a very hard time going back to a pre-1988 now.
heh i always liked the way a 85 handled especially after i put 225/50/15 v rated's i actually liked the bump steer go way too fast for a corner and let off gas which would dip ur front around the corner
next question does anyone know which cradle gets more traction on launch? or are they the same
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09:29 PM
FrdFrmBrdn Member
Posts: 17 From: Beacon Falls, CT, USA Registered: Nov 2010
so if i mount a sway bar and solid cradle bushings is it as good as the 88 cradle? or still no.
im trying to keep the handling better then stock so should i upgrade what i have or search for a 88 cradle?
im planning on putting a high hp 3800 in
Your first question, no adding a solid bushing and a sway bar which will help will not come close to what the 88 cradle has. The main reason, as said before is the tri-link suspension. which is way better then the setup.
Second, if you want better handling the cheapest road out with good results (I think, and I say this cause I'm sure someone is going to reply and say I don't know anything) is to add a rear sway bar from either an 88 Fiero rear or just take a stock front bar (any year) and mount it in the rear with a set of end links, bushings and brackets you can buy at most auto stores. Buy a set of Koni rear adjustable struts, and Eibach springs, I'm not sure of the size measurements but I'm sure someone here has them. but get a set of springs with what ever rate you want. 250 lbs is obviously softer then 325 lbs springs. Again I'm sure everyone will have a say as of to which rate is best for what ever setup you want to do. Then get a set of threaded sleeves and nuts for height adjustment.
$60 per spring $40 for sleeves and nuts Koni rear struts (summit racing) pn# KON87411063 price $224 Special D $20 rear sway bar used $25 bushings and mounts $653 Total (Full Coil over set-up for the rear)
so for less then $700 you can have a setup on your car that is better then the stock 88 setup (and I say STOCK set up) throw a set of Koni's and springs and acc. on an 88 and you cant compare to the 84-87. But like I said, this is the best bag for the buck. If you want, I can pull my info of my car from my folder and get the spring dimensions and rates, threaded sleeve size and length as well as part numbers for them. Just keep in mind, if you do this to the rear you should really up grade the front springs to match (and I don't mean match spring rates, front rates will be different) at the very least, if not shocks as well. For the front I used QA1. Also the strut and spring info are the same between 84-87 and the 88's. The fronts are different but everything I said was from when I had an 86 SE. I have an 88 GT race car now.
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10:41 PM
Oct 24th, 2012
Marvin McInnis Member
Posts: 11599 From: ~ Kansas City, USA Registered: Apr 2002
so if i mount a sway bar and solid cradle bushings is it as good as the 88 cradle? or still no.
im trying to keep the handling better then stock so should i upgrade what i have or search for a 88 cradle?
In my opinion, you should always restore the stock systems to perfect working order, and drive them for a while, before you ever consider modifying them.
[This message has been edited by Marvin McInnis (edited 10-24-2012).]
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01:22 AM
PFF
System Bot
thedrue Member
Posts: 1104 From: Vancouver, WA USA Registered: Feb 2009
I am a very big fan of the 88 rear suspension. I do not have any side by side comparisons between the two different rear suspensions but this thread outlines my 88 cradle upgrade and has many pictures of the swap in progress. Shows off the new rear suspension very effectively.
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01:47 AM
Fieroking Member
Posts: 2150 From: Coeur D Alene Idaho USA Registered: Jun 2002
As stated the major difference between the two cradles is the mount points for the cradle and the total change on the suspension. Now you can mount the pre 88 cradle into a 88 chassis you can't modify the upper mount points for the struts. You can mount the 88 cradle into the pre 88's you have to install coil overs and use a relocation kit for the upper strut mount. The upper mount on the 88 strut tower was moved in 1 inch and forward 1 inch. You can not use the 88 rear sway bar on a pre 88 cradle, you can mount a front sway bar from a 84 to 87 however it is mounted under the cradle.
Joe Sokol
------------------ 85 SE Daily driver with a 3.4 DOHC OBD II 88 Formula/GT 4.9 Allante Intake (My Baby) www.fieroking.com
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01:49 AM
Reallybig Member
Posts: 974 From: Calgary Alberta Canada Registered: Mar 2011
Originally posted by Marvin McInnis: In my opinion, you should always restore the stock systems to perfect working order, and drive them for a while, before you ever consider modifying them.
Yes. I agree with this as well. Really one needs to restore the stock suspension to OEM specs before you do any sort of serious modifications to truly understand what you are doing and have done to the car. It also will help you understand the true dynamics of how a Fiero handles. Remember, the YOUNGEST Fiero is now nearly 25 years old.
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Originally posted by Reallybig: My 88 came with the 2.5 and no rear sway bar. They aren't easy to find and you need the brackets that bolt to the struts as well for them to work.
The four cylinder 1988 models did not come with the rear sway bar. I'm guessing GM did not think that the rather non-performance oriented four cylinder model would require such an item, thus only the 1988 GT and Formula models got the bar. With only around 12,350-ish or so total '88 GTs and Formulas built, it can be difficult to find a salvaged unit.
. If you want, I can pull my info of my car from my folder and get the spring dimensions and rates, threaded sleeve size and length as well as part numbers for them. Just keep in mind, if you do this to the rear you should really up grade the front springs to match (and I don't mean match spring rates, front rates will be different) at the very least, if not shocks as well. For the front I used QA1. Also the strut and spring info are the same between 84-87 and the 88's. The fronts are different but everything I said was from when I had an 86 SE. I have an 88 GT race car now.
could u please? ya i plan on doing front too this fiero will be better then stock in every aspect
They aren't easy to find and you need the brackets that bolt to the struts as well for them to work.
