Parabolic springs in production.

[abaddonxi]

I keep hearing tell how wonderful parabolic springs are, the common comment being that they provide a ride similar to coil springs.

So, how come they don't come out on new cars, say Toyotas?

I know everyone also talks about the cost, but I'd have thought that in new car production the performance gain and economies of scale would cover the extra cost on standard springs.

So, what's the bounce?

[Slunnie]

AFAIK the issue is more to do with interleaf stiction rather than the parabolic shape of the leaves. If you have a look at many of the newer leaf sprung vehicles, many of them have gone from having 11 leaves down to 3 or 4 with poly buttons between the leaves.

[UncleHo]

G'day Abaddonxi :)

The Falcon powered Transit vans of the 80's had them,only about 2 leaves from memory, Post Aust had heaps of them.


cheers

[101 Ron]

Why stuff around with Parabolas with there hard to manufacture and shape leafs when coils are a piece of wound wire.
Parabolics I think wouldn't be in the mind of modern independent suspension designers.
In the 1960s (and much later in the 1980s with corvette )car makers used a single leaf and as it had no friction and located the drive axle.
The problem being the spring can only be single rate.
A coil can be progressively wound for the same job.
Multi leaf parabolics are a improvement over normal leafs for ride, but will lack the longer wheel travel off road as you don't have leaf sliding over leaf and this gives more flex.
I think its more for the designed job of the vehicle with production costs compared to other systems compromises etc
Normal leafs are so much easier to make.
Landrover did fit parabolics standard on some models.