torque boxes

[drifter69]

gettig ready to weld in torque boxes, can I do this with the car just sitting on frame or will it need to be sitting on the suspension?

[tan top]

if it  were me would weld with weight on wheels 

[drifter69]

The car is on the rotisery right now and no suspension under it. I was going to paint next so if I can do it without suspension under it that would be great. If I do weld them in can I put stands under it where the suspension ties in? I do have the sub frame conectors in so the car is not flexing as much as it use too.

[Mike DC]

  
IMHO probably the best thing you could do without reassembling the car is to just prop it up on jackstands at the suspension mounting points.  

Use a pair of jackstands at the front subframe rails, underneath the shock towers at the rear K-frame mounting points.  Put a pair of jackstands in back (it'll need to be some pretty tall jackstands) at the rear axle's bumpstop.  Right at the top of the rear subframe rail arch.  With the unibody sitting relatively level and supported like that, it should mimic the load points of an assembled car sitting on the suspension pretty well.  The jackstands are also nowhere near the torque box areas so that should make the job less of a PITA. 


The rotisserie gets too much leverage at the ends compared to a normal assembled car.  The missing drivetrain mitigates a big portion of that problem, but I think it would still be better to have the car sitting on well-placed jackstands for installing torque boxes or connectors.  

[tan top]

 
IMHO probably the best thing you could do without reassembling the car is to just prop it up on jackstands at the suspension mounting points.  

Use a pair of jackstands at the front subframe rails, underneath the shock towers at the rear K-frame mounting points.  Put a pair of jackstands in back (it'll need to be some pretty tall jackstands) at the rear axle's bumpstop.  Right at the top of the rear subframe rail arch.  With the unibody sitting relatively level and supported like that, it should mimic the load points of an assembled car sitting on the suspension pretty well.  The jackstands are also nowhere near the torque box areas so that should make the job less of a PITA. 


The rotisserie gets too much leverage at the ends compared to a normal assembled car.  The missing drivetrain mitigates a big portion of that problem, but I think it would still be better to have the car sitting on well-placed jackstands for installing torque boxes or connectors.  

true

[drifter69]

Thanks, I am going for it like you said. Thanks for the advise!

[elacruze]

I wouldn't worry about it much. The boxes add strength but they are flexible so they will accomodate some flex.
On my car, it was on the rotisserie but the frame connectors were jacked into the floor enough to take the weight off the ends of the car. The interior had already been crossbraced before putting it on the rotisserie so it didn't move much in any case. The boxes were welded in on the rotisserie without consideration for flex, since the connectors were fully welded in beforehand.
I think the most important thing is to make sure the car is flat, that is measure to see that the rear spring hangars, torsion bar mounts, and front suspension mount points are all equal to their other-side counterparts before you weld. That way you know the car is not twisted.
For the boxes, the car may be flexed a little from front to back and it won't matter so much, but with full-weld frame connectors the front-rear flex matters a lot more since it affects door and glass alignment.