The 14 Car Performance Therapy Project Rushforths, Baers, Yokohamas, and more

[NOT A TA]

With the subframe and suspension in place so the car could sit on four wheels it was time to start fitting sheet metal. Trunk lid was first up and with some tweaking the new (used) lid lines up nicely. So I moved on to the front end where my first task was to figure out if the 81 subframe would work with the 70 core support.

The later frame mounting holes for the core support are farther apart than on the early frame and the directions for the PTFB solid body mounts say they can't be used with the 70-73 Firebird core supports. BUT, I paid for the solid mounts and I'm using them! I marked and opened up the body mount holes in the subframe to fit the sleeves that come with the PTFB solid mounts. While opening up the holes for the solid mounts I found that the bushings wouldn't sit flat inside the frame rail because of the way the frame is made (like the rear most body mounts) so I welded in some sheet metal pieces I made.







Next used my tram gauge to measure and mark the core support for the new body mount location and larger diameter. Then opened up the holes in the core support for the mounts. I made the holes slightly bigger than necessary to allow a bit of side to side and fore/aft adjustment of the core support.

I had poly body mounts previously I installed back in the 90's. At the time I used a 1/2" thickness bushing between the frame and core support as instructed. I always had a lot of shim stacks to get good fender/bumper/hood gaps and so I'm test fitting the body panels with the thick 1" bushing between the frame and core support to see if things fit well with them (if not I'll switch to the 1/2" and test fit again). If the 1" bushing doesn't work out I'll come back and modify this post.