So i've had spohn's SFC's sitting in a box for months, and its time to get them installed. My query is.... if I just have them welded in, won't they "lock" the car in position with the middle sagging down?

I'm thinking I need to find a shop with a frame rail or something to compenstate for the sag in the middle before it's welded? What do you guys think?

Thanks,
Bill

 

Sorry, but Im unable to help You. But I really wanna know the same thing ... So I will kinda just tap into this thread.

 

if you actually have "sag", then I would jack under the center of the car, slightly, thus pre-loading the sfc's - I did this with my vert, it helped some issues I had. I've yet to see a hard-top or t-top for that matter that was actually sagging, the doors, fenders, etc may be mis-aligned/sagging, but the body usually is not. The biggest issue is torsional stress(twist), which the sfc's can eliminate.

 

Well, there's no visible sag. But, I know that there has to be some invisible sagging going on. I do have a hardtop, and there are small stress cracks (which I thought only t-tops and vers suffered from!)... and that's with only 50,000 miles. There are also scratches in the paint in the door wells.

 

Your scratches are more likely from worn door hinges. If you're worried about it, get your car checked at a frame shop before you install the SFCs. There's probably nothing wrong with it, though.

 

What if i had the SFC's installed when the car was on a frame rail? Or is that not distributing the load properly or some cr*p?

 

most reccomend installing the sfc's while the car is sitting on the suspension(as in sitting on the tires). If you do it while suported from the frame you risk improper "loading" of the sfc's, and you could mis-align things(like the doors, the body). - As I said before, I doubt any of these cars are actually "sagging".
-wgripp - those stress cracks are from twist, yes hardtops get it too(verts don't, we don't have a roof to crack). - the doors are probably worn hinges, VERY comon with or 10,000lb doors. - CHP just did an article a couple months back about some new/improved greaseable(built in zerk fitting) door hinges for our cars, could be a big improvement.(I'm old-school, mine were long ago adjusted via the 2x4 in the door jam, pull and check until "re-aligned")

 

If your car sags, you have major issues and installing SFCs should be the least of your concerns right now.
In the position he is referring to in this quote, your car should not sag. A proficient F-body supported under the lower A frames and the rear end housing will not sag in the middle.

 

Thanks for your help guys. I'm dropping my car off tomorrow to get worked on a J&S Performance in PA. Josh runs it, and is a member on here!