New engine cradle doesn't line up (Page 1/2)
gln103 MAY 14, 05:23 PM
I'm in the years-long process of doing an 3800 engine swap on a 1987 GT. Because my original engine cradle was rusted out, I purchased a used engine cradle, which is in great shape, and, to the eye, looks identical to my old cradle. When I tried installing this new-to-me engine cradle in the car (literally just the cradle...no engine, no transmission, etc.), the cradle mounts don't line up with the body mounts. If I install the 2 front mounts first, then the cradle's rear is shifted to the passenger side of the car's body mounts by ~0.5". Instead, if I install the 2 rear mounts first, I can get the front/passenger mount bolt in, but the front/driver mount is ~0.5" off. I tried prying it into place with crow bars, but I can't get stuff to move that much.

Before I do something ~drastic like slotting one of the front body mounts, does any of this make sense to anyone? Are there engine cradles whose body mount points are ~0.5" different?
Patrick MAY 14, 05:26 PM

I suspect one or the other has been bent out of alignment from a collision... but let's see what others might have to say.
gln103 MAY 14, 07:04 PM
I compared the old cradle to the new cradle, and the new one is definitely bent . Any suggestions to DIY bend the cradle back close to original? If not, any sources for a good used engine cradle?
cartercarbaficionado MAY 14, 07:10 PM

quote
Originally posted by gln103:

I compared the old cradle to the new cradle, and the new one is definitely bent . Any suggestions to DIY bend the cradle back close to original? If not, any sources for a good used engine cradle?


get a bfh. big (text expunged) hammer, or you can take it to a body shop with a frame puller and for 100-300 bucks they can straighten it properly, if you need it to be straight for pretty much free your best bet is to chain (i recomend a tow strap rated for above 8k pounds) it to a tree and use a come along (or a tractor and strap for safety but a truck also works) and just keep pulling on the bend area to spread the front mounts, if you need em closer just get a pipe wrench and huge pipe and heave til it fits
olejoedad MAY 14, 08:18 PM
Where is it bent?

I've seen the rear mount towers be tweaked, the front horns be bent in or out, but I've not ever seen the center square area the holds the drivetrain be distorted.
mcguiver3 MAY 14, 09:30 PM
In thinking about your issue, I believe the new cradle being square (that can be verified by cross measuring) then the car frame is tweaked and that is where the straitening should occur.
If the front mounts on the frame are OK then possibly drilling out the rear that is out of wack may be good bet.
Raydar MAY 14, 09:55 PM

quote
Originally posted by mcguiver3:

In thinking about your issue, I believe the new cradle being square (that can be verified by cross measuring) then the car frame is tweaked and that is where the straitening should occur.
If the front mounts on the frame are OK then possibly drilling out the rear that is out of wack may be good bet.



I would rather believe that the cradle is tweaked, and not the car. If it is indeed the cradle, it needs to be square, otherwise the angle of the side rails will place one rear wheel slightly ahead of the other, by the time the "unsquare-ness" is translated all the way out to the ball joints. 1/4 - 1/2 inch out of square may not be critical, but it certainly could be.

I would measure the cradle corner-to-corner, then repeat in the opposite direction. The measurements should be identical.

Not arguing with you. Just saying it in a different way, I suppose. If the cradle is indeed square, then yeah...
(From the Department of Redundancy Department.)
olejoedad MAY 14, 10:06 PM
Measure both cradles, corner to corner.

The old cradle fit, those measurements should be the benchmark.
My bet is that the front 'arms' or one of them, is bent slightly.
gln103 MAY 15, 09:55 AM
Great info guys...this is why I love this forum!

The new (to me) cradle is definitely bent. I don't know the cradle's history, because I bought it from the Fiero Factory years ago, but it looks like the passenger side, rear wheel hit something and bent that side of the cradle back. As @olejoedad suggested, I compared corner to corner distances between the good and bad cradles, and the bad cradle was bent back and slightly in by nearly 2"! So, with a come along, I started pulling corner to corner, and I'm getting it closer. I'll tweak it more over the coming days and let you all know how it goes.
fierosound MAY 15, 10:40 AM

quote
Originally posted by gln103:

So, with a come along, I started pulling corner to corner, and I'm getting it closer. I'll tweak it more over the coming days and let you all know how it goes.



From the manual in metric (millimeters - 25.4 = 1 inch)


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[This message has been edited by fierosound (edited 05-15-2024).]