Rear seat brace vs bulkhead.

[Tony1968]

No offense to anyone. I honestly believe that everything is just a bandaid to the real problem. The frame and the old rubber body mounts. Just my opinion but reinforcing the frame correctly and using something harder than rubber (poly) should reduce flex greatly. Having done both i still added the X brace. Jmo.

 

[Clone TIE Pilot]

No offense to anyone. I honestly believe that everything is just a bandaid to the real problem. The frame and the old rubber body mounts. Just my opinion but reinforcing the frame correctly and using something harder than rubber (poly) should reduce flex greatly. Having done both i still added the X brace. Jmo.

I agree, it should be mentioned that rear seat braces won't really work without the #5 bushings installed.


Boxing the frame would be the best fix but its a complex and delicate procedure. To box a frame correctly it should be clamped into a chassis jig and back step welded to minimize heat warpage.

 

[pagrunt]

Boxing the frame would be the best fix but its a complex and delicate procedure. To box a frame correctly it should be clamped into a chassis jig and back step welded to minimize heat warpage.

With out clamping into a jig might remove the warping from when they were originally put together.

 

[Tony1968]

I boxed mine with Hellwig kit. Following instructions to a T. Measured carefully prior. When done it hadn't moved at all. If I remember correctly less than a sixteenth of an inch. Body went back on with zero issues.

 

[-dw-]

No offense to anyone. I honestly believe that everything is just a bandaid to the real problem. The frame and the old rubber body mounts. Just my opinion but reinforcing the frame correctly and using something harder than rubber (poly) should reduce flex greatly. Having done both i still added the X brace. Jmo.

I wasnt paying attention or ignoring all this bracing all these yrs. I havent changed much on my car for nearly the last 20 yrs. One of the last changes I made way back when were solid body mounts. That surely seemed to firm up the way the car felt.

 

[Tony1968]

I agree, it should be mentioned that rear seat braces won't really work without the #5 bushings installed.


Boxing the frame would be the best fix but its a complex and delicate procedure. To box a frame correctly it should be clamped into a chassis jig and back step welded to minimize heat warpage.

I believe these are the bushings you speak of...

 

[doood]

After reading all the spirited discussion on the rear seat brace in this and previous threads, I've come to 3 conclusions:

1. Not going to install the tubular bolt-in brace I got from Mike's Montes years ago but never installed
2. Not going to spend $270 for any stamped sheet metal brace no matter how well is fits
3. Will buy strips of 0.100 steel and bolt/rivet install with seam sealer

Was going to use reproduction rubber body mounts; but I'm hearing good things about the urethane.

 

[doood]

I believe these are the bushings you speak of...
View attachment 231918

You have really beefed up the LCA to frame connection with the weld-in and the UMI bolt-in. I have the UMI bolt-in, and will install when I swap in the 8.5 this spring.

 

[Hurricane77]

I believe these are the bushings you speak of...
View attachment 231918

I'm not even sure those do a lot since there's no provision to actually bolt to the body in that location. Maybe there is a on GNX, but my 87 Cutlass just has a place for that bushing to rest, there's no cage nuts there or anything.

 

[Clone TIE Pilot]

I believe these are the bushings you speak of...
View attachment 231918

Those are the two #5 location bushings. Some G bodies did not come with those installed from the factory.