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Changing to 88 cradle without pulling motor or trans. by dematrix86gt
Started on: 08-23-2013 08:29 PM
Replies: 19 (507 views)
Last post by: sardonyx247 on 05-01-2014 01:35 AM
dematrix86gt
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Report this Post08-23-2013 08:29 PM Click Here to See the Profile for dematrix86gtClick Here to Email dematrix86gtSend a Private Message to dematrix86gtEdit/Delete MessageReply w/QuoteDirect Link to This Post
I want to change my 86 to the 88 Cradle. I can bridge the motor and trans to hold it in place and drop the cradle. has anyone done this swap this way? encounter any probs?
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Report this Post08-23-2013 08:40 PM Click Here to See the Profile for trotterlgClick Here to Email trotterlgSend a Private Message to trotterlgEdit/Delete MessageReply w/QuoteDirect Link to This Post
lot of other work needs to go on besides just change the cradle, probably really better to just take it all out. Larry
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Neils88
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Report this Post08-23-2013 09:40 PM Click Here to See the Profile for Neils88Click Here to Email Neils88Send a Private Message to Neils88Edit/Delete MessageReply w/QuoteDirect Link to This Post
I'd also be concerned with safety, there are a number of points that really can only be undone from underneath if you don't have the whole cradle assembly sitting on a dolly in front of you. Being under an engine on a hoist is just plain wrong...It can obviously be done, but by the time you've pulled the exhaust, mounts, suspension etc, you'll find that it all would have been a thousand times easier outside of the engine bay. The drop is extremely simple...don't take a chance, drop the whole cradle/engine/transmission assembly and then do it properly.
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dematrix86gt
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Report this Post08-23-2013 09:52 PM Click Here to See the Profile for dematrix86gtClick Here to Email dematrix86gtSend a Private Message to dematrix86gtEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have a bridge that attaches to the strut towers and front and rear bulkheads that holds the motor and tranny in place so no chance of it falling. but seems i need to read more on this swap. i was just thinking other than the struts/ brakes it was pretty much a straight forward swap over. thanks for the info ill read up more before attempting it.
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Fiero84Freak
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Report this Post08-23-2013 10:15 PM Click Here to See the Profile for Fiero84FreakClick Here to Email Fiero84FreakSend a Private Message to Fiero84FreakEdit/Delete MessageReply w/QuoteDirect Link to This Post
It's a lot more than just brakes and shocks.

GM realized by 1988 that the bushings holding the cradle to the frame were kind of junk, so for the final year of production they were eliminated for a solid pedestal style mount setup. While the actual mounting points are not different, the biggest concern will be that the shock setup is entirely different from all prior years. When the A-arms from the prior setup were eliminated in favor of the much-better independent tri-link setup, it necessitated a different strut design to clear the components and it mounts to the '88 space frame differently. GM had to re-tool the space frame jig slightly for the last year of production to account for the new strut top hat mount point. You either have to completely modify the frame work around where the strut top hat mounts, or build a custom coil over setup. You just can't use the '88 struts along with the cradle and it bolt up.

I'll also ask as well why you want to do this. You can make the 84-87 setup handle pretty well. Most of the common issues with the earlier styles - outside of the design - are worn bushings and rubber components. You can get aluminum cradle sleeves to eliminate the cradle bushings, making it similar to how the '88 cradle "hard mounts" to the space frame. Then you can simply re-fresh all the suspension bushings, and install a rear sway bar (like putting a spare front bar on the rear, or upgrading the OEM front bar and then moving the OEM front bar to the back). Of course, you will ultimately be limited by the A-arm setup and it's rather limited range of motion & in addition there still will be some degree of "bump steer". However the above modifications will do wonders for the car, especially if it is still on stock components. Hard mounting the '84-'87 cradle will eliminate the "cradle slop" which really affects turning geometry (when the cradle bushings wear out and you turn the car at speed, the cradle continues in a straight line until it "hits" the extreme point of wear = cradle slop). Fresh bushings in the suspension (they don't have to be poly) and a rear sway bar will help to tie in each suspension pivot point to one another, and reduce - but not eliminate - the bump steer.

Having owned an '88 Formula (which is essentially an '88 GT) and almost every other year Fiero, I can tell you that the most pronounced advantages the '88 setup has over other years is a bit smoother ride quality, and at the front end a much lower scrub radius at low speed (the front was redesigned for '88 also). But you can make pre-'88 model Fieros drive just as well so long as you're willing to put a bit of work into it.
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FieroJosh1993
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Report this Post08-23-2013 10:28 PM Click Here to See the Profile for FieroJosh1993Click Here to Email FieroJosh1993Send a Private Message to FieroJosh1993Edit/Delete MessageReply w/QuoteDirect Link to This Post
I asked the same question a few months ago. I had to change the cradle because the one on the car at the time was rusted and falling apart. I asked if I could just drop the cradle and leave the motor and trans. Everyone said no, I tried it anyways, the biggest issue I ran into was the exhaust system goes under the cradle, and you can get to the lower exhaust manifold with out have the car on a lift. I spent 3 days trying different things. nothing worked, I had to drop the engine. It was that bad. Its a right of passage when you own the Fiero, lol. Just wanted to share.
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dematrix86gt
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Report this Post08-23-2013 10:50 PM Click Here to See the Profile for dematrix86gtClick Here to Email dematrix86gtSend a Private Message to dematrix86gtEdit/Delete MessageReply w/QuoteDirect Link to This Post
My exhaust uses band clamps and can be easily taken off in no time at all. I already have installed a rear swaybar and yes it tightened everything up and basically tied the car together. As for why i am looking into this,as i said i thought it would be a straight swap (but its not) yes ride quality is what im in search of. i want to sort out the ride situation before starting on the body. motor swap and trans work has already been done. would coilovers achieve the ride im looking for? now its kinda like riding on a bucket, not bottoming out just very stiff. its not the swaybar causing it because it was stiff before adding the swaybar. Im not new to working on fieros ive been working on them for years but am new to owning one. ive had this one since may and i love it.
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Report this Post08-23-2013 10:55 PM Click Here to See the Profile for TXGOODClick Here to visit TXGOOD's HomePageSend a Private Message to TXGOODEdit/Delete MessageReply w/QuoteDirect Link to This Post
I don`t know how much of a difference there is in an 88 cradle but Ben(Marine1981) and I changed out the cradle on his 86 and it was pretty much a breeze.
We just took the engine hoist hooked it to the engine and just slightly lifted the weight off of the cradle.
Then just dropped it with the exhaust and struts and mostly everything still on the cradle except engine and transmission.
Lifted the other back in and reconnected everything.
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Report this Post08-24-2013 10:43 AM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
I would do it that way, with the exhaust out of the way the engine and tranny supported the cradle comes right off. While the cradle is out swap out the engine mount and bracket with an 88 one and put the 88 cradle back in. Most of the changes for the 88 cradle are in the suspension and dealt with in the wheel well not the engine bay. Having a second set of hands will make it a lot easier to help move things around to line them up. Dan

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cvxjet
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Report this Post08-24-2013 01:16 PM Click Here to See the Profile for cvxjetClick Here to Email cvxjetSend a Private Message to cvxjetEdit/Delete MessageReply w/QuoteDirect Link to This Post
I changed to an 88 cradle on my 85 SE while leaving the engine and trany in place; I admit I used a large part of my French vocabulary on it, but it was a lot easier than draining and disconnecting everything. The exhaust just drops down after the two bolts on the coupler are removed, although reconnecting the springs that hold the rest of it in place was......"Fun". And a number of people offer coil-overs for the rear which are needed because of the different angle of the spring-strut assembly.

By the way, it sure is nice to run thru a corner, hit a "Whoop-d-do" and have the car track true.....I've owned my 85 v6-se since new and it always had a wiggle in the back- Hulki and crew did a great job on this car considering their budget and the animosity from upper management, but Strut-suspension 101; The toe link should of been shorter than the A-arm, not longer, due to it's position between the arm and the top of the strut.
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olejoedad
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Report this Post08-24-2013 04:23 PM 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
As stated, drop off the exhaust and change to the 88 engine mount bracket, much easier than dropping drivetrain.
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Fieroking
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Report this Post08-26-2013 01:37 AM Click Here to See the Profile for FierokingClick Here to visit Fieroking's HomePageClick Here to Email FierokingSend a Private Message to FierokingEdit/Delete MessageReply w/QuoteDirect Link to This Post
The only thing I have to say about this is. There is a right way and a wrong way to do a cradle swap and you are GOING DOWN THE WRONG ROAD.

Joe Sokol

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Report this Post08-26-2013 06:12 AM Click Here to See the Profile for EvilSqueezlesClick Here to Email EvilSqueezlesSend a Private Message to EvilSqueezlesEdit/Delete MessageReply w/QuoteDirect Link to This Post
Arrautmotorsports.com sells a bracket for this swap. Runs around 80$ I believe. Basically it bolts up to where the stock strut assembly does and moves the mount point out I believe to match up where the 88 strut needs to be. Also you need to widen the front mounting points a bit and elongate the holes in the frame where the rear cradle bolts go. Nothing too bad though.

[This message has been edited by EvilSqueezles (edited 08-26-2013).]

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Raydar
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Report this Post08-26-2013 06:24 AM Click Here to See the Profile for RaydarClick Here to Email RaydarSend a Private Message to RaydarEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by EvilSqueezles:

Arrautmotorsports.com sells a bracket for this swap. Runs around 80$ I believe. Basically it bolts up to where the stock strut assembly does and moves the mount point out I believe to match up where the 88 strut needs to be.
...


The tops of the 88 struts are actually located inward.
This is why the coil-overs are required. Not enough room for the big spring in the shock tower.

To the topic at hand...
I don't see this as being even as ugly as swapping a tranny while leaving the engine in place.
I've done that before.
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Report this Post08-26-2013 07:41 AM Click Here to See the Profile for TXGOODClick Here to visit TXGOOD's HomePageSend a Private Message to TXGOODEdit/Delete MessageReply w/QuoteDirect Link to This Post
As I said above I don`t know what all is involved in swapping to an 88 cradle from an older one but the actual act of dropping the cradle and lifting in another is not a big deal.
Of course, with anything some people can and some people can`t.
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Report this Post08-26-2013 07:59 AM Click Here to See the Profile for TONY_CSend a Private Message to TONY_CEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by EvilSqueezles:

Arrautmotorsports.com sells a bracket for this swap. Runs around 80$ I believe. Basically it bolts up to where the stock strut assembly does and moves the mount point out I believe to match up where the 88 strut needs to be. Also you need to widen the front mounting points a bit and elongate the holes in the frame where the rear cradle bolts go. Nothing too bad though.



To use the strut adapter bracket, you need to use coilovers. Also,
I didn't have to widen the front mounting points or elongate any holes for the cradle. The 88 cradle fit right into my 84 chassis. How ever you do it, whether you drop the engine or just the cradle, believe me, it is worth it to use the 88 cradle. The first time you hit a bump while taking a corner you'll be glad you spent the time to do the swap.
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hdryder
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Report this Post04-30-2014 12:53 PM Click Here to See the Profile for hdryderClick Here to Email hdryderSend a Private Message to hdryderEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by TXGOOD:

I don`t know how much of a difference there is in an 88 cradle but Ben(Marine1981) and I changed out the cradle on his 86 and it was pretty much a breeze.
We just took the engine hoist hooked it to the engine and just slightly lifted the weight off of the cradle.
Then just dropped it with the exhaust and struts and mostly everything still on the cradle except engine and transmission.
Lifted the other back in and reconnected everything.


I have an '86 GT, with an older 3800 SC Series I motor swap, that I bought cheap last year. There must have been a bad battery in the car at one time, as the only rust on the car is a totally rusted out battery tray, and the cradle bellow the battery tray is very rusted, making a weak location on the cradle at that point.

My plan was to support the engine and transmission, then remove the bad cradle and install a good spare cradle that I have on hand.
It seems to me to be do-able if safety is the number one aspect of this job.
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2.5
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Report this Post04-30-2014 01:34 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 dematrix86gt:

yes ride quality is what im in search of.
would coilovers achieve the ride im looking for? now its kinda like riding on a bucket, not bottoming out just very stiff. its not the swaybar causing it because it was stiff before adding the swaybar.


So is your issue you want a softer ride? That would be primarily your struts being firm and if you have larger rims with low profile tires that is another big one. Most of the time I hear people going to coilovers because they want suspension even more firm.
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TXGOOD
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Report this Post04-30-2014 02:09 PM Click Here to See the Profile for TXGOODClick Here to visit TXGOOD's HomePageSend a Private Message to TXGOODEdit/Delete MessageReply w/QuoteDirect Link to This Post
I`m not sure on a 3800 swap, I guess a lot depends on the exhaust.
On the 2.8 exhaust you can just disconnect the one place in the front where the manifolds hook to the rest of the exhaust and the rest of it stays with the cradle.
Leave the dogbone connected and the engine/tranny should pretty much stay in place.
The only problem we had was that the replacement cradle had the holes in a slightly different place which took some prying but that was probably due to the car taking a slide into the curb so it could have repositioned the mounts a little.
We did it that way so that we wouldn`t have to disconnect all of the crap that goes to the engine.

[This message has been edited by TXGOOD (edited 04-30-2014).]

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sardonyx247
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Report this Post05-01-2014 01:35 AM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
I did this when I solid mounted my cradle, I even decided to change my pan gasket while I was under there, real easy just support the engine.
We have a support that goes across the car to hold the engine up.
BTW one of the prevous posts is wrong, all years use the same struts. Springs, location etc are different, but the struts are the same.

exhuast hard?!? not even, two bolts and the exhaust drops with the cradle.


edit to add: I used something like this http://www.harborfreight.co...pport-bar-96524.html

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[This message has been edited by sardonyx247 (edited 05-01-2014).]

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