Rear Leaf springs
Rear Leaf springs
(OP)
Is there any real advantage of replacing the conventional multiple stack leaf spring setup with a (single) rear leaf spring of the same rate. To me it seems like a real headache but others around me think that this is the way to go?
Could someone shed some more light on this subject with the advantages if any & also the disadvantages related to this!
Keeping in mind this is a race car & no rear bar is permitted by the rules in this particular class!
Thanks.
Could someone shed some more light on this subject with the advantages if any & also the disadvantages related to this!
Keeping in mind this is a race car & no rear bar is permitted by the rules in this particular class!
Thanks.





RE: Rear Leaf springs
Cheers
Greg Locock
RE: Rear Leaf springs
No taper in the design at all, basically what they are planning is just like a heavier main leaf spring by itself!
The length of the spring from eye to eye is a little over a
1mtr in length.
When questioned about advantages they will not elaborate, which is suspect to me!
Thanks
RE: Rear Leaf springs
1) The spring will be heavier than necessary for it's spring rate.
2) The spring will concentrate the stress near the "U" bolts, as the ends near the shackle will be to stiff, and therefore not share the load evenly.
Regards
pat pprimmer@acay.com.au
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RE: Rear Leaf springs
The weight disadvantage of the proposed design is considerable.
Cheers
Greg Locock
RE: Rear Leaf springs
My thoughts exactly!!
RE: Rear Leaf springs
RE: Rear Leaf springs
Assuming that "supplemental" lateral location devices such as Panhard bars or Watts links are also illegal, you probably wouldn't want these things to be tapered in plan view either.
I think the older Chrysler Corp. cars (circa late 1950's/early 1960's, before some of their cars sported proper rear sta-bars) sometimes used extremely stiff bushings in the front spring eyes for hard cornering applications, which would have added some roll rate. Does this product use a similar attachment point detail?
Norm
RE: Rear Leaf springs
Cheers
Greg Locock
RE: Rear Leaf springs
Thanks for the design concepts, i can tell you, that this design doesn't come close to what you have suggested! But it may be worth a re-think!
Thanks
RE: Rear Leaf springs
RE: Rear Leaf springs
We damper manufacturers go to great lengths to reduce friction. It does the opposite of what you want from a damper, in that it is highest at zero velocity, dropping off sharply as motion begins. This is referred to as 'stick-slip'.
Returning to the leaf spring, I use 'parabolic' leaf springs on a Landrover. These are lighter than the originals, even if the same rate is selected. This is because the spring is optimised by reducing it's section toward the ends. They do, however, allow more axle 'wind-up'. I intend to try to remedy this by using a hybrid spring, with a single leaf, tapered toward the shackle end, and parallel (or less tapered) toward the chassis bush end. As Norm suggests, this is probably the aim of the single leaf.
RE: Rear Leaf springs
RE: Rear Leaf springs
RE: Rear Leaf springs
After many race & test miles with the single leaf setup of all configurations, best we get a shovel & bury it!!
The conventional stack of springs is much more user friendly for this application & much easier to tune quickly not to mention it stays on the track much nicer & is much more stable under brakes as well!!!