I'm wondering why more people don't do tube engine cradles for their swaps. Looks terribly easy to do :

Any thoughts ?

DLD

where can you buy those at or do you just make them yourself? i was looking on using something like this for my N* swap. that would make it a bit easier to do the swap i would think.

Would be super-easy to just do yourself.

You can buy them, but they want rediculous money for them.

By building your own cradle, you don't have to come up with some gimp'd-up tacked-on angle-iron engine mount goofyness.

DLD

Lots of folks don't know how to weld.

I think that if someone were to fab up a replacement cradle that was adaptable to various swaps using bolt-on mounts and brackets, it would be a good seller. (Think "northstar", especially.)
It would be even better if it would directly replace an 88 cradle, since the 88 cradles are more fragile, and also since the 88 rear cradle/suspension is a popular swap into earlier cars.

Just MHO, of course.

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Raydar
88 3.4 coupe...........

Praise the Lowered!
Read Nealz Nuze!

Bump?

I've thought about building one for shts and giggles just because. It'll save some weight but there are no really big advantages to a tubular cradle vs stock that I've seen so far.

quote Originally posted by caddyrocket: I've thought about building one for shts and giggles just because. It'll save some weight but there are no really big advantages to a tubular cradle vs stock that I've seen so far.

Running stock drivetrain, I'd agree. But for *any* swap that doesn't use stock engine mounts, seems like the way to go to me.

Think I'll do some checking in to that. Prev poster was correct in that it's a great opportunity for bolt-in engine mounts for different applications.

DLD

Here is one I made. I raised the lower a-arm pick up points and took out the roll steer. Uses '88 components.

Gusshotrods subframe is a lot stronger than the one at the top due to the arrangment of turbing even though there is little triangulation. Consider that 100's of pounds of force that go through the control arms when cornering. There is nothing to keep it from bending inward at the forward control arm pivot point. To build a subframe you need to build a sturdy jig first that your original sub will bolt in to at all the various points. So first you would get your northstar or whatever mounted and running true with no vibration, I.E. exactly where it should be. Then take it all apart, build a jig, then build a new sub. Once you have the jig, you could sell plenty of subs for $800 each or more, powder coated in different colors along with tubular lower control arms. It's a lot of extra work for just one car though.

quote Originally posted by RacerX10: Running stock drivetrain, I'd agree. But for *any* swap that doesn't use stock engine mounts, seems like the way to go to me. Think I'll do some checking in to that. Prev poster was correct in that it's a great opportunity for bolt-in engine mounts for different applications. DLD

That's a good point. Not totally sure why that didn't occur to me except that I had been staring at my TDC all afternoon lol. I've been putting the pen on paper for a longitudinal LS1 twin turbo swap into a Fiero over the last couple months and that will obviously require a ton of custom fabrication including a new cradle.

quote Originally posted by fiero4.3L: Gusshotrods subframe is a lot stronger than the one at the top due to the arrangment of turbing even though there is little triangulation. Consider that 100's of pounds of force that go through the control arms when cornering. There is nothing to keep it from bending inward at the forward control arm pivot point. To build a subframe you need to build a sturdy jig first that your original sub will bolt in to at all the various points. So first you would get your northstar or whatever mounted and running true with no vibration, I.E. exactly where it should be. Then take it all apart, build a jig, then build a new sub. Once you have the jig, you could sell plenty of subs for $800 each or more, powder coated in different colors along with tubular lower control arms. It's a lot of extra work for just one car though.

You and gusshotrod understand what I'm getting at.

I've seen people cutting up and re-welding cradles for as long as I've been watching people do engine swaps.
Perhaps there's a market for a custom made cradle. I'm thinking that two or three variations on one basic design ought to be sufficient.

The first variation would have the front crossmember (and whatever else) relocated to provide a bolt in option for Northstar swaps.
The second variation would have the left channel "massaged" (and whatever else) to accommodate Archie's LT1 installations.
The third variation could be more like a stock 88 cradle (with all the appropriate strength adders and slotted mounting locations), for the 3800 and 4.9 folks.
All of them could have humps in the appropriate (whatever that may be) places to accommodate custom exhaust system routing, etc., etc.

Ths could kill a whole flock of birds with only a couple of stones.
The 88 cradle is more fragile than the earlier ones, but it's also sought after for retrofit into earlier cars. (A couple of adapters, coilovers, and the 88 suspension bits, and you're there.)
And of course, there are those of us who just don't know how to weld, who would be doing engine swaps if it weren't for that one single issue.

[This message has been edited by Raydar (edited 10-31-2005).]

I allways liked this one.

David Breeze

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Pantera Rebody Kits

quote Originally posted by opm2000: I allways liked this one. [IMG] David Breeze

Isn't that the one being done by the folks in Florida? If it's the one I'm thinking of, it's specifically designed for the 3800.
It's a nice piece for sure, but it doesn't have the 88 suspension points. I looked at their website, and they mentioned nothing about support for 88s.

[This message has been edited by Raydar (edited 10-31-2005).]

My shop is a race car factory We could throw these things together over lunch.

Here's a pic of my last fab job :

DLD

There is less toe in under acceleration and less toe out under braking with the '88 design. The acceleration/braking loads are transferred to the unibody more efficently. Also, adjustment for anti-dive and bite can be easily incorperated with a series of holes in the cradle to locate the front of the for/aft links. There are a couple of holes you can't see in the cradle I made for this purpose.

For me the weakest part to a stock cradle (88) are the crossmembers. When I solid mounted my SBC, I removed the stock ones and put in new ones made from 2x3x1/8" wall. I also moved both cross memebers about 1" to the front to get more room and raised the rear cross member up so a muffler could lay flat in front of the trunk

I have thought quite a bit about making a new tubular cradle, but it hasn't gotten to the top of the list yet. Here is one I have drawn up in AutoCAD it is still a work in progress (like how to protect the oil pan):

quote Originally posted by RacerX10: My shop is a race car factory We could throw these things together over lunch.

It's 1:45. Ya' done yet?

You mentioned gusshotrod's use of the 88 suspension pieces...

I suspect that, given the option, many (most?) people would prefer the 88 configuration.
As it is now, the 88 rear cradle/suspension retrofit is quite a popular swap into earlier year Fieros.
Also, someone with an 84-87 car who is shelling out the bucks for an engine swap and a replacement cradle isn't going to mind the few extra dollars that the 88 suspension pieces are going to cost.
Of course, there will be exceptions.

Fieroguru... Very nice work! I agree about the crossmembers. Specifically, where the front tranny mount bolts to the cradle.

[This message has been edited by Raydar (edited 10-31-2005).]

quote Originally posted by Raydar: Isn't that the one being done by the folks in Florida? If it's the one I'm thinking of, it's specifically designed for the 3800. It's a nice piece for sure, but it doesn't have the 88 suspension points. I looked at their website, and they mentioned nothing about support for 88s.

I don't know who or where they are, or were. Their website was sort of ellusive in that there was no location given. I tried their website ( fieroevolutions.com ) several times today without success, and they may be out of business.

But your right, that cradle was shown with a 3800 or 3800SC mounted.

I thought the interesting thing was the modern control arms, lightweight knuckle ( I think ) and aluminum calipers. That might be better than the '88 suspension parts, I don't know.

David Breeze

[This message has been edited by opm2000 (edited 10-31-2005).]

quote Originally posted by opm2000: I don't know who or where they are, or were. Their website was sort of ellusive in that there was no location given. I tried their website ( fieroevolutions.com ) several times today without success, and they may be out of business. But your right, that cradle was shown with a 3800 or 3800SC mounted.

I remember that website, now. I remember not getting a "warm and fuzzy" because of the complete lack of a location.

I believe those are the same folks who brought a "display" to the 20th, in Michigan.
That was a pretty sweet setup. 3800 swap -all connectorized -plug 'n' play. Looked like it could have been done in an afternoon.
But holy hell were they expensive!

quote I thought the interesting thing was the modern control arms, lightweight knuckle ( I think ) and aluminum calipers. That might be better than the '88 suspension parts, I don't know.

The only problem I see is the same problem that affects the original suspension. The toe links are connected to the rear of the cradle.
The big deal with such a setup is that when the rear suspension is unloaded, it steers the wheels outward.
Picture this scenario... You're entering a turn, and halfway through, you realize that you are going too fast. (Never happens. I know. )
You drop the throttle, or worse, nail the brakes. The momentum causes the weight to shift to the front of the car. This causes the front tires to bite a little better than they were, probably pushing the nose on around the turn. So far so good.
But as the rear suspension unloads, it causes the outside rear wheel to steer outward. Toward the outside of the curve. Where you already are trying not to go. So now the front is trying to take the curve and the rear is trying to go around. Spin city.

There are control arms available that locate the inside ends of the toe links on the control arms. Those probably would work better (true for stock cradles, as well.)
Anyway... Sorry for rambling.

[This message has been edited by Raydar (edited 10-31-2005).]

How much would a custom cradle cost?

My modified cradle cost me $30 for the steel and welding. Did the sizing myself. I retain the stock transmission and suspension mounting points. My cradle gained a few pounds with the heavy front crossmember, but its not significant. Its plenty strong for a N*.

A custom cradle seems overkill, unless its for a longitudinal swap or all out racecar.

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Buy a fiero, become a mechanic
3.4 dohc Install
Sub Install
Northstar Install

quote Originally posted by gushotrod: There is less toe in under acceleration and less toe out under braking with the '88 design. The acceleration/braking loads are transferred to the unibody more efficently. Also, adjustment for anti-dive and bite can be easily incorperated with a series of holes in the cradle to locate the front of the for/aft links. There are a couple of holes you can't see in the cradle I made for this purpose.

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I have a bump steer kit I bought a few years ago that corrects the geometry causing toe change by altering the distance between the toelink pivots. I think it was around $100 from a guy in Texas. I cant go measure right now but it shortened the toe link by 3 inches using a rodend for the inboard end and a special shaft threaded to work with the rod end and the stock metric outer tie rod. The arc from the shorter link matches the arc the spindle makes through its travel. It works very well.

Once I rebuild this 440t4 I'm going to rework the crossmembers with a kickup for exhaust like that shown above, a higher mount for my remote oil filter, and pipes running along the cradle so the hoses wont be so long and strung across the top. My water pump isnt flipped like on sbc's.

How about something like this:

by Dave Held, previously of Held Motorsports.

Here's the site: http://specificmotors.com/kit.html

Bob