my integra is feeling a bit rubbery on the corners
so I was wondering how would I identify if its bushings flexing or the unibody is blown out and flexing more than it should on hard corners

I feel like its the unibody blown out but don't know how to confirm it

except one possible sign
car vibrates like a mother f with stock motor and hasport street mounts.

put same mounts in another car and its smooth like b16 at idle...

I was thinking while engine is out do some seam welding but thought I discuss it here first which one is better seam welding of using strut bars.

 

Does either car have torque mounts?

If the car is still on factory bushings, they could probably stand to be replaced.

Most strut bars wont do ****.
I will say this, I put a Nuespeed bar in my civic and i did feel difference with cornering.

 

Kinda wondered about troubleshooting the body also. My car has developed a pretty loud creak in the rear during hard cornering, its been slowly getting worse. So far I have been unable to locate the source...

 

Check the subframe around the sway mounts?

 

my main concern is vibration in the cabin

I feel like the chasis is just blown out on the spot welds and is vibrating at 900-1100 rpm really bad.