Is the birdcage only present on C3's?

[Brassplyer]

The title pretty much says it - is this a structural issue on Vettes besides the C3?

Clarification after csherman's reply below - was it present on generations after the C3?

 

[csherman]

No
The birdcage was started - in 1963
The late 56 on up had alum metal reinforcements bolted in to give strength to the dash and door posts
53 54 55 did not have any inner structure - thus the dashes sag because the windshield is so heavy and people snap their conv tops tight drawing down the dash

Chris

 

[Brassplyer]

No
The birdcage was started - in 1963

I just amended the OP after your response. Was it present on later generations?

 

[csherman]

After c3 / the C4 had a birdcage - then they went to a "backbone" frame design

 

[Hib Halverson]

When you say "birdcage", if you mean the metal structure which surrounded the cockpit and bolted to the frame of a '63-'67 and '68-'82, then the '84-'96 C4 did not have anything like that.

The C4 used what GM called a "uniframe" which was not only a structure surrounding the cockpit, but also was the car's chassis. C4 did not have a separate structure around the driver which bolted to a frame.