So, what are parabolic springs?

The original leaf spring suspension fitted to Series Land Rovers is affectionately referred to a “cart springs”. These springs are made up of up to 11 elliptical “leafs” bolted together in the middle (where the axle sits) and fixed to the chassis at either end. As the vehicle travels over uneven ground, the leaves “bend” and transmit the force from the axle to the chassis. During this movement, the leaves move against each other, but before they can begin to move, they must overcome the “inter leaf friction”, and with 11 leaves, touching along their entire length, this is quite a lot of friction. Over time, with the build up of dirt and corrosion, the interleaf friction become higher and the suspension less effective.

Parabolic leaf springs on the other hand, have just 2  leaves (more if required but not higher than 4) that only touch at the ends; therefore less interleaf friction. The materials used are are a lot stronger so few leaves are required to handle the force transmitted from the axle.

They also allow for a smoother ride and improved axle articulation.

There are a few manufactures out there, the bees knees being those from Heystee Automotive in the Netherlands but they come at a price. I’ve opted for Rocky Mountain Parabolic Springs from Canada.

In this instance, the downside to fitting these springs is that it raises the ride height of the vehicle by about 1.5 inches which means, dear reader, I wont be able to get the finished vehicle out of the garage without replacing the up and over garage door.

At the same time I fitted some new stainless steel brake pipe shields from Bits4Landys as the originals were made  of mild steel and by this time paper thin and not much good for anything.

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New springs offered up to the front axle. The holes in the bottom plates (flat metal objects to the outside of the springs) had to be drilled out to 13mm dia to allow the thicker U-bolts to pass through. (and before you say it, yes I know they are the wrong way round in the picture)
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Springs fitted ready for the wheels
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I missed some photos of the rear axle. This is the first attempt at fitting the springs. Its easier working upside down.
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Doh…. Wrong. Can you spot it? The brake pipe shield (silver metal bracket in the middle of each spring) should be on the opposite side of the axle, (facing towards the rear) thats the trouble working upside down
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Brake pipe shield now in the correct location.
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The old road wheels back on makes shifting things about a lot easier.