So, whoever disassembled my 67 roadster did not mark the torsion bars when they came off (and I am happy to say that wasn’t me!). There are markings on them, one appears to have the part number C9331, but I don’t see any other clear markings. I see only one part number in the parts book, so apparently they are the same when installed and just pick up their twist during use. A new set is around $500.
So any suggestions for what to do about this? I guess it’s a 50% chance that I get them the right way round. What would be the consequences of getting it wrong? Will it be clear that they are in fact wrong?
John, as the left side passes close to the exhaust maybe look for indications in the paint that one side looks different than the other. Swapping the sides will reverse the load on the torsion bar and might not be good. Tom
Are you sure there isn’t a small l or r stamped on one end or the other? It can be hard to see, and is typically not aligned with the part no stamping.
An engineer told me reversing them after years of use could cause catastrophic failure, ie, snap and your on the ground.
Try magnafluxing them to find one clear mark.
John, one thing you may want to try is to have someone under the age of 40 look carefully at the ends. Chances are they may be able to pick up faint markings. I marked mine when I removed them but wanted to double check. I could not see markings even with magnification but my son had no problem identifying them.
Do the main part of the shafts exhibit the same level of corrosion as the ends? It doesn’t take much corrosion on the main part of the shaft to reduce the spring rate (which varies with the 4th power of the diameter).
For what it’s worth, I have become a proponent of replacing with new ones, if you have everything apart, after seeing stories of ride height issues with original bars.
I would not powder coat them.
Powder coat is cured at 400f for 10-15 minutes.
Annealing spring steel is in that temperature range.
The bar could be rendered useless if not cured below 350f.
I’d also be concerned with the effect of corrosion on stress levels. A smaller bar has greater stress for the same twist angle, rough calculation suggests the % effect on spring rate and stress is quite similar for a small reduction in diameter, say 0.5mm. The effect of increased stress, though, is likely to be more unpleasant than reduced rate.
Since these bars are also subject to bending stress which is beyond my ability to estimate, I’d be very wary of any stress raiser such as corrosion or scratches.
All the above comments are general since I have no direct experience with the E-type components.
