I have a 81 vette, in pretty decent condition, aside from some rust on the frame and birdcage. The frame overall has some surface rust and an actual hole on the drivers side frame rail (near rear of door) and floor pans are rusted through very badly. My original plan was to have the frame fixed sometime in the near future by a pro but unsure of the cost, and slowly restore the car. And I would do the floor pans myself. To make a long story short, (if I want) I can have a new RUST FREE frame and birdcage (tub) from another 81 vette for FREE.

I'm not a pro by any means, and I guess my question is, would I be getting in over my head swapping my current car over to another frame and cage? Or would it be easier just to have my frame repaired and do the floor myself? This is my first experience with a corvette, was actually the first vette I have driven. My experience is mostly engine/electrical systems etc. I do not know much about body and frame work but I'm very mechanically inclined.

The new frame is appealing to me because I could have it cleaned up and powder coated before installation, which I would not be able to do on my current frame. Money is also an issue, I would like to take care of most of the work myself. (in my garage). Any suggestions on shop tools that would make this swap easier? I don't want to take up another space in the garage with a frame I don't have the means or ability to use.

 

Well, I would opt to swap whatever I could (rotted parts).
Now, the "birdcage" is not the floors. Most of the birdcage is concealed
behind fiberglass panels.
If the BC is allright (not likely if frame holes), then a frame swap isn't too bad
and the floors can be replaced at any time (body on or off).

You can inspect parts of the BC by removing the kickpanels, and removing
the #3 body mount access panels in the front of the rear wheel wells.
Take a look in these places for rot.
Next, reach under the rocker panel mouldings ... put your fingers
between the frame rail and the steel rocker channel (part of BC).
Pull outward on the rocker channel along the length and feel for any
significant flexing. The channel should be solid. At this point, you should
be starting to get a good idea of the birdcage condition.
If BC is good - plan on just the frame swap and salvage the floors from the other vette.
If BC is bad, you'll have to decide to repair or swap the rear clip out (cowl back body).

I swapped frame and rear clip ... lots of work. Good Luck.

 

Swapping a birdcage is a MAJOR undertaking. The birdcage was the first part to be welded up and attached to the floor pan in the body shop. The entire body is essentially bonded to the birdcage (front clip, rear clip, sills, etc,). Other parts are installed on it (glass, doors, dash,). Swapping the cage would be equivalent to replacing the foundation under your house.

You don't want to go there if you don't have to.

 

It is actually a frame/floors/birdcage, the whole thing. He called it the entire tub. It is complete,totally rust free, just need to swap everything from mine over to it. Gonna try to get some pics up today. It came about when I just wanted the floor pans cut out, to replace my rotted pans. So instead of cutting up a perfect vette, he is willing just part with the frame and all. It sounds like an odd deal just to avoid cutting floor pans, but this is actually taking care of several issues.
Oh, and yes my cage is in pretty sad condition.

 

If your frame and bird cage are rusted and the donor parts are good then I dont understand why you would hesitate. Maybe I dont understand your situation. Peace,,,Moosie

 

Look before you leap. The VIN of each of these Corvettes, yours and the donor car, is attached to the birdcage. You will want to check with the DMV in your state to determine whether you can legally swap VIN plates.

 

Yup, was already thinking about the VIN situation. Gonna look into that this afternoon.

 

It's easy to suggest swaping birdcages ... unless you've done it.
Even with the entire rear body from the cowl back ... it is LOTS of work.
You need to break off the front of the car and ACCURATELY glue
it back on. I am now getting gray hair ... attributed partially to all this
work and worrying about messing it up. I ended up with small issues
that have been resolved.

Floors ... MUCH easier to replace. Just check the birdcage on your
body before starting in on any swap. EDIT: Sorry - went back and saw you think yours is definitely bad.

Also, as Mike pointed out, the visible VIN # will be the one from the donor.
That is, unless you illegally swap the VIN tags (and do it right without getting caught).

To swap birdcages, you will need to break almost every factory
fiberglass bond on the panels surrounding the cage. I would look around
for another cowl-back body for sale with solid cage and fiberglass intact.
SERIOUSLY ... they are fairly cheap when you find one ... say $250-500.
WELL worth the savings in work, aggravation, and worrying.
I'm on year 4 ... and just getting to interior and sanding exterior.