Those 4-leaf springs look really good for being 40 years old (compared to a lot I’ve seen).
1 cm between sides is not noticeable.
Been my experience (others experience may/will vary) that most cars over 20-30 years old, the rear springs will sag about 2-3 inches (5-8 cm).
I would be saying a figure closer to 6 cm figure (maybe 6.5?) would be needed.
Note: be sure to adjust your front torsion bars after rears get back together.
Then, car will need to be re-aligned because a few different alignment angles will have changed.
While springs are off, be sure to replace the rear shackle bushings (fairly cheap).
If the front bushings are broken or have heavy cracks in them, you might want to consider changing them as well. If not broken or heavily cracked – I would leave them alone.
Something I do on my own cars – is I place a stud, steel rod or something similar into the front bushing holes – to firm up the bushings. The average person might not notice anything, but if you drive car hard (which I do), you can notice the difference.
I don’t recommend polyurethane for front bushings or for shackle bushings.
That said, I do recommend to either toss the Iso-Clamp system and use the older shock plates OR replace the rubber biscuits with polyurethane ones.
http://www.energysuspensionparts.com/5.6106
Note: this is one source of these pads – there are others out there as well.
Note: I recommend using the older style shock plate – but many here have used the poly pads (above) without any issues.
Either version will make car handle much better
BudW
1 cm between sides is not noticeable.
Been my experience (others experience may/will vary) that most cars over 20-30 years old, the rear springs will sag about 2-3 inches (5-8 cm).
I would be saying a figure closer to 6 cm figure (maybe 6.5?) would be needed.
Note: be sure to adjust your front torsion bars after rears get back together.
Then, car will need to be re-aligned because a few different alignment angles will have changed.
While springs are off, be sure to replace the rear shackle bushings (fairly cheap).
If the front bushings are broken or have heavy cracks in them, you might want to consider changing them as well. If not broken or heavily cracked – I would leave them alone.
Something I do on my own cars – is I place a stud, steel rod or something similar into the front bushing holes – to firm up the bushings. The average person might not notice anything, but if you drive car hard (which I do), you can notice the difference.
I don’t recommend polyurethane for front bushings or for shackle bushings.
That said, I do recommend to either toss the Iso-Clamp system and use the older shock plates OR replace the rubber biscuits with polyurethane ones.
http://www.energysuspensionparts.com/5.6106
Note: this is one source of these pads – there are others out there as well.
Note: I recommend using the older style shock plate – but many here have used the poly pads (above) without any issues.
Either version will make car handle much better
BudW