So im humiliated to ask this but what exactly are torque boxes on a fox body. Is it where the lower control arms bolt onto the chassis at the rear? I keep on reading about how people strengthen there torque boxes before adding some serious power and ive seen what the weld on plates look like, im just not sure where they go! Do you weld them over the original mounting plates?

 

Generally people reinforce them when the car has already been damaged. Now, rumor is that the TQ should be fine until you start running a tire or hooking up, that said there is no reason you can't reinforce them anyways.

Downside is you have to pull the carpet up at least or risk fire.

The parts are cheap, $90 box here for a Foxbody.

The lower control arms come off the axle housing and connect to the TQ Boxes on the underside.

Heres a pic i snagged from online.

 

i imagine if one of the mounting points crack that would be really f-cken bad as in control arm shoots out and coil spring goes flying

 

I think you would notice it if it cracked and was knocking long before you lose other suspension parts, this of course is if youre dailing driving.

If you are launching at 6k at the track on a slick and it lets go, that is another story

 

They are a good upgrade for our rusty cars up here, but if your torque boxes are still in good shape and you're not always at the track.... don't bother installing them until it's necessary. Most people start running into the issue of cracked torque boxes once they switch to stiff bushings/control arms with slicks and hard launches. Of course, rust plays a big part in this too.
SS

 

well Most people start running into the issue of cracked torque boxes but you lose other suspension parts. all is just because of rust.

 

check your torque boxes. and its better to installing them. rust is is big problem.