TAC Spotlight => Projects & Restorations => Topic started by: d_hache on August 26, 2021, 07:59:56 AM

Title: 1980 Trans Am Subframe Mesurments
Post by: d_hache on August 26, 2021, 07:59:56 AM
Hello everyone, i have my subframe at a welders to fix the metal around the bushing holes.
As most of you probably know those can wear \ thin out with time.
I got a plan online with the measurements but some of the measurements seam to be off.
Can you tell me if this is the right one for a 1980?

(https://i.postimg.cc/62nxCXnx/Subframe.jpg) (https://postimg.cc/62nxCXnx)


I also found this one, all the measurements seam good minus the F which is not even close.
On the diagram F says 32 7/8 but we have 28/3/4 on the actual subframe?
Help please

(https://i.postimg.cc/yJR7z0GX/Screenshot-2021-08-26-at-2-36-49-PM.jpg) (https://postimg.cc/yJR7z0GX)


Title: Re: 1980 Trans Am Subframe Mesurments
Post by: 81Blackbird on August 26, 2021, 11:49:45 AM
There are some plans out there that have a few more cross values. If you can't find one you can do it yourself.  Just make sure you have the tape measure located in the same position on each side.  This will determine if the frame is square.  Also, get a rod the with a slightly smaller diameter than the bolt holes for the lower A-frame.  The rob should slide through all four holes.  If it doesn't something is bent.
Title: Re: 1980 Trans Am Subframe Mesurments
Post by: d_hache on August 26, 2021, 12:23:48 PM
thanks for info will check for square, make sure frame is square
If someone has a subframe that is off the car would be interested to see your F measurements as shown on diagram.
Let me know
(https://i.postimg.cc/yJR7z0GX/Screenshot-2021-08-26-at-2-36-49-PM.jpg) (https://postimg.cc/yJR7z0GX)
Title: Re: 1980 Trans Am Subframe Mesurments
Post by: d_hache on August 26, 2021, 12:28:18 PM
Just to let you know that we checked and frame is square
Title: Re: 1980 Trans Am Subframe Mesurments
Post by: NOT A TA on August 26, 2021, 07:18:08 PM
A lot of the cars got worn lower A arm holes from bumping parking blocks back when they were daily drivers. The most likely hole to be messed up is the rear hole of the rear mount drivers side. The design of the lower A arm mount wasn't very good. I sell a kit to reinforce the mounts. With the increases in cornering grip available with today's aftermarket suspensions, brakes and tires we can put forces on the mounts and sub frame the car was never designed for.  More info about the mount design here https://lab-14.myshopify.com/products/75-81-late-2nd-gen-f-body-lower-control-arm-mount-reinforcement-kit-9-16