Hey guys, does anyone have any experiance putting an 88 rear cradle or more specifically, doing a suspension swap on an 86 Fiero?? I want to take the '88 cradle and suspension and throw it into my 86 Fiero. I heard that there may be some fabrication or modification to the cradle needed? Can anyone confirm? Is there a kit??

You have to go to coilovers on the struts, & relocate the top inboard & forward. Held makes a kit for that which moves the strut in 2" & forward 1".
You'll also have to shorten the coolant pipe behind the engine on the left side, & get a different hose (a longer flex hose works well).
The engine mount under the timing chain will have to be extended & re-drilled to match the cradle bolts.
You have to get shorter bolts for the rear cradle.
Exhaust spring mounts may be different or missing.
Have I forgotten anything, guys?
~ Paul
aka "Tha Driver"

Custom Fiberglass Parts

quote Originally posted by Tha Driver: You have to go to coilovers on the struts, & relocate the top inboard & forward. Held makes a kit for that which moves the strut in 2" & forward 1". You'll also have to shorten the coolant pipe behind the engine on the left side, & get a different hose (a longer flex hose works well). The engine mount under the timing chain will have to be extended & re-drilled to match the cradle bolts. You have to get shorter bolts for the rear cradle. Exhaust spring mounts may be different or missing. Have I forgotten anything, guys? ~ Paul aka "Tha Driver" Custom Fiberglass Parts

Yes on the strut relocate. Held kit is easiest ( westshorefabricators.com ). Yes on the coilovers (make or buy). Possibly on the coolant hose though mine works OK without any changes. A bit tight but it works. On the engine mount just use the 88 one. Get one from the mall if you need to.

On the cradle bolts its best to just use the 88 fiero bolts. If all you have is the 86 bolts then I'd suggest you buy the correct ones. Fierostore has them.

Brakes!! Its not recommended to use the vented 88 rear brakes with the non vented 86 fronts. Find an upgrade that works on all years of fiero. There are a few options out there. Easiest and chapest I've found is to use the grand-am upgrade on the front and stock 88 brakes in the rear. No matter what you choose keep in mind you will need to either machine or buy machined front hubs. 84-87 fieros have the hub and rotor as one assembly.

Dispite the work and $$ involved this is one surperb upgrade for the early fieros. Well worth it!

[This message has been edited by Fieroseverywhere (edited 06-22-2011).]

thx guys!!

Well, i'm buying an '84 with t-tops, and was curious about doing this procedure myself... Is there any particular reason the front brakes can't be upgraded to 88 style along with the rear?

Did just the rear suspension change on the 88, or did the front change as well? What's involved in that swapover?

Anything else special involved in carying an 88 engine along with the cradle besides the ecm?

How well does an 84-87 with 88 rear cradle swap handle compared to an 88?

Old post, I know...

I'll second what Knight asked... is it mainly a difference in bumpsteer? Mine has a few rear upgrades (I haven't really looked in depth but it appears rear poly arm bushings were installed, and it has a rear sway bar), but I've always wondered if there's a major difference between '84-'87 and '88. I want to do something like an L67/F23 swap in mine someday, and I figure if I'm going that far I may as well collect parts for an '88 cradle swap.

PS I got some Vodka in me so I'm not so stingy on thread revivification

quote Originally posted by Twilight Fenrir:Anything else special involved in carying an 88 engine along with the cradle besides the ecm?

Honestly I don't think there's a difference, all the sensors should be the same and everything would likely be plug & play. The only differences I could think of would be the connector shape/pinout.

I built a 383 for my '92 C1500 (originally 4.3/4L60) and used an EBL controller (www.dynamicefi.com). I put a 454 throttle body on (larger throttle bores than 4.3/5.0/5.7 that used the same TBI body), and the IAC/TPS plugs are different. Other than that everything worked like factory, and the engine is capable of (probably) close to 425hp with the right heads.

The EBL is frickin' awesome if you want a stock-like setup. It replaces part of the stock ECM, and you can order it already done, or as a DIY-style board if you're semi-capable of soldering. You can tune in semi-real time (aka you make changes and can flash the ECM as you're sitting there in the car) through a serial-to-USB adapter. You can easily adjust parameters like the timing curve, how early idle speed lowers (aka the "high speed cold idle"), lean cruise (helps even MORE with mpg, something the Fiero isn't exactly a stranger to), etc. A wideband O2 sensor setup is required to take full advantage of the EBL's VE (fuel trim) learn capabilities.

[This message has been edited by Doober (edited 02-13-2013).]

And what front and rear brakes do you use?

Jonathan

quote Originally posted by Boostdreamer: And what front and rear brakes do you use? Jonathan

I swapped the 88 cradle into my 84 and I used the 88 rear brakes and the e-brake set up from the 88 also. I also changed over to the 88 master cylinder and brake booster and modified the front hubs to accept re-drilled 87 Vette 12" rotors. Then I made new brackets to accommodate the 88 Fiero front calipers as well. I am planning on making some brackets for the rear so I can use the Vette rotors on the rear wheels but right now I am just using the stock Fiero 88 rotors and the car stops amazingly well.

I am doing just the opposite, I done an 88 cradle swap with my l67/F23 swap and am running vette 12in. rotors in the back using the 88 calipers with the stock 86 front brakes until I can get the front bracket worked out. By the way I love the 88 suspinsion, it makes the car handle a lot better.

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86GT, 3800SC, F23, true duals, 3.4 pulley, comp VS cam, zzp power log, WCF air intake, ARP bolts, comp lifters and push rods, 90# springs, SI stainless valves, aero-force scantech meter.
Here is my build thread https://www.fiero.nl/forum/Forum2/HTML/122548.html

quote Originally posted by Knight: How well does an 84-87 with 88 rear cradle swap handle compared to an 88?

Again I ask. Just wondering.

Never driven a car before/after a cradle swap. Maybe someone can chime in.

I have the 88 rear in my car. I used Held strut relocating brackets and their coil over kit.

You need to notch out the strut towers top to accept the relocation plate and drill a few holes. It's very easy.

I put poly on the entire rear at the same time.

You need to get an 88 front (under the crank) engine mount, or modify the pre 88 to work. If you search it I think you will find the info. I found an 88 to use, buyt the mod wasn't a big deal if I remember right.

I have the 88 rears with the pre 88 fronts and it still stops pretty well. The fronts lock up well before the backs in the wet. In the dry it seems more even for some reason. An adjustable proportioning valve would probly do the trick, but I haven't done it yet.

Ok, is it better? It's been a while, but the difference is night and day for me. Other will tell you the same I'm sure, but I can run the car at 9/10 all day. It is very recoverable at 11/10. The original rear end would have me doing end swaps, now you can let off the throttle at any point through a turn and it just settles back into traction as the speed bleeds off. I really didn't like the twitchy feeling of the original. I like the 88 for sure.


Chay

Anyone know cost to have someone stretch the 88 cradle?

Build a wooden jig to properly lengthen the cradle and align the mounting points. Take the cradle and jig to a welding shop. You might be surprised at how affordable it will be since the jig will save them a lot of setup and execution time.

[This message has been edited by olejoedad (edited 05-12-2013).]

That is an excellent idea! (Sorry for hijacking).

quote Originally posted by olejoedad: Build a wooden jig to properly lengthen the cradlethe and align the mounting points. Take the cradle and jig to a welding shop. You might be surprised at how affordable it will be since the jig will save them a lot of setup and execution time.