I just recently bought a 87 trans am with t-tops. After looking at all the tell tale areas and inspecting the chassis and subframe I have determined that this thing has had a hard life as most have had. People have jacked it up in the wrong spots, bottomed it out over god knows what and its all crushed underneath. After I repair all that is crushed I planned on building my own subframe connectors to tie EVERYTHING together. However without knowing all of EXACT dimensions that these cars should have, I'm thinking of just buying already made subframe connectors since they are already engineered to be the exact lengths they need to be. This way I wont just be tieing everything together in its twisted state. Then adding more of my own fabbed connectors once the pre-fabbed ones are in. Chassis experts please chime in on your thoughts. I know that chassis work needs to be done with the cars weight on its wheels which is the way the car moves down the road. But with the pre fab connectors I'll do it with the weight off the wheels and the car in the air to hopefully get its proper geometry back.

 

Anyone???

 

Maybe I missed it but what was your question?

 

You're saying the subframe is bent and distorted? If thats the case, it's not worth the money to properly correct.

If you're saying it looks a little beat up but everything is straight, sure, throw on some bolt in SFC's to make sure nothing is badly beat up and then raise the car on a drive-on lift and have the SFC's welded in permanently.

I'm with midias, I'm not exactly sure what the question is...

 

i feel like i just listened to a joe biden speech, im totally confused.

 

If you are fussy, find a body shop with a Car-o-liner and they can straighten it out using the original factory spec.

A simpler way to check the body is to get a tap measure and make sure the distance between the front and rear wheels is the same on both sides.

Otherwise don't worry. Just buy some sub frame connectors, weld them in and off you go!

 

You could find a totally flat area, jack the car up and put 4 equal height jack stands under the 2 torque boxes and the front frame rails. If the car is tweaked it won't sit evenly. Also, do the body panels line up and do the doors open without a lot of resistance?

If any of those tests yields weird results, frame rack.

 

If your car has any real frame damaged wouldnt you have a rebuilt title too? Assuming it was reported.

 

Also, do not weld them in with the car in the air. I'd say most, if not all members on here other than Vetruck got theirs put in with the car on its wheels on a drive on lift. Vetruck recommended sitting the car on 4 equal height jack stands on the suspension load points and using a jack to tweak the chassis back straight if it's out of alignment (one of the jack stands isn't touching the body). Vetruck's method would be ideal but frankly most people would be hard pressed to find such a level slab, let alone set up and weld there.

These cars flex when they're in the air, and not in a good way. On cars with a lot of miles (fatigued chassis) the doors will usually be hard if not impossible to open. If you weld the chassis like that it won't be loaded as it was designed to be and opening the doors will be a PITA as well.

I went through all of this before I did my SFCs. My car had low miles and the chassis was still straight and fairly rigid but my driver side sat slightly higher which I now contribute to the passenger side spring sagging a bit. If it'll give you peace of mind, frame rack it. If you just want to check yourself,
a. Drive through water with the wheel perfectly straight. If you see two tire tracks, the car tracks straight. If you see 3 or 4, the car is bent sideways.
b. Look at the car at just slightly left or right of straight on from the front or rear. If any body panels are out of alignment, it's suspicious. Doors sag and cars get hit so it isn't guaranteed that the frame is goof'd at that point but frame racking it at that point is a good idea.
c. Jack stand trick described above
d. Take diagonal measurements across the bottom of the chassis. Everything should be even.

After that, just make sure the car is on a drive on lift and weld away. If the car is really sloppy, run an outer and inner set of SFC's, a wonderbar, a strut brace, and consider seam welding the chassis too. Should be far stiffer than brand new and go on 3 wheels when the suspension finishes articulating.

 

this should help!

 

Finally someone that have posted excacly what I have been looking for.
I have had some problems with my car since the day I bought it.
Doesn't sit well on all 4 frame rails when put on jack stands.

So I guess this is a good way to check for frame unstraightness.
Thanks you my friend