Lowering a 67 dart
Turning the torsion bars does not effect spring tension! It just alters the angle of the lower control arm. If you lower it too far though it will ride like crap, for 2 reasons. 1-you won't be able to set the caster/camber properly with stock a-arms, you'll end up in positive caster and thats not good. 2- You'll end up riding on the bump stops. This is likely why you ended up with frame damage.
If you want your car to handle (it doesn't weigh anywhere close to 5000 lbs btw), you'll want to get new torsion bars and rear springs. Up front I'd go with .94 to 1.09" bars depending on what you're plans are. In back you can go with XHD or SS springs, but the SS springs will raise the rear. You can get around this somewhat with new spring hangers, the new ones have 2 holes, one about 1.5" above the other, for a little bit of a drop. You may need new hangers anyway, I broke several studs on mine when I tried to remove them. Then you can go with blocks and longer u-bolts if you still need them.
If you're going to use a drop spindle, I'd use Magnumforce's new spindles. I have them on my challenger, and they're excellent parts. They're cheaper than the Fatman spindles, and are single piece cast units like the originals, not fabricated multi-piece units like the Fatman's. They also use the later '73-up spindle, so you can convert to 11.75 disks while you're at it if you want, or just use the easier to find '73 up rotors. The drop spindles will make you life easier if you want to keep the stock a-arms, since you'll retain the standard caster/camber settings.
Sway bars are a good thing to have too, although they become somewhat less necessary if you run stiffer bars/springs. Keep track of your wheel rates if you can, if you run better bars and springs you may not need huge sway bars.
And a good set of shocks will help things too, KYB's aren't bad but the adjustable QA1's are better.
Here's the Magnumforce setup with 11.75" rotors...I know I've posted it up before...
Turning the torsion bars does not effect spring tension! It just alters the angle of the lower control arm. If you lower it too far though it will ride like crap, for 2 reasons. 1-you won't be able to set the caster/camber properly with stock a-arms, you'll end up in positive caster and thats not good. 2- You'll end up riding on the bump stops. This is likely why you ended up with frame damage.
If you want your car to handle (it doesn't weigh anywhere close to 5000 lbs btw), you'll want to get new torsion bars and rear springs. Up front I'd go with .94 to 1.09" bars depending on what you're plans are. In back you can go with XHD or SS springs, but the SS springs will raise the rear. You can get around this somewhat with new spring hangers, the new ones have 2 holes, one about 1.5" above the other, for a little bit of a drop. You may need new hangers anyway, I broke several studs on mine when I tried to remove them. Then you can go with blocks and longer u-bolts if you still need them.
If you're going to use a drop spindle, I'd use Magnumforce's new spindles. I have them on my challenger, and they're excellent parts. They're cheaper than the Fatman spindles, and are single piece cast units like the originals, not fabricated multi-piece units like the Fatman's. They also use the later '73-up spindle, so you can convert to 11.75 disks while you're at it if you want, or just use the easier to find '73 up rotors. The drop spindles will make you life easier if you want to keep the stock a-arms, since you'll retain the standard caster/camber settings.
Sway bars are a good thing to have too, although they become somewhat less necessary if you run stiffer bars/springs. Keep track of your wheel rates if you can, if you run better bars and springs you may not need huge sway bars.
And a good set of shocks will help things too, KYB's aren't bad but the adjustable QA1's are better.
Here's the Magnumforce setup with 11.75" rotors...I know I've posted it up before...
