Monkeyboy said:
Wait for it ... wait for it ...
Teri Ann will have a great explanation of her modification of the o.e. springs.
I take it I have been invited to provide information about an alternative to parabolic springs. Since the original question was about which brand Parabolic spring and not whether stay with leaf springs or use parabolic springs I was going to stay out of it. Sorry but I can't resist the invitation.
But first:
I only know of three Sources: British Steel, Rocky Mountain and Heystee Automotive (formally T.I. Consoul). Hopefully other folks can provide additional info about parabolic manufacturers and the products out there on the market.
Paul, owner of
Heystee automotive was the first to offer Parabolic springs for Series Land Rovers. He started off with Santana springs and since then has worked with the company that manufactures Santana Parabolic springs to farther refine the spring design to work better with Land Rovers.
Wise owl started out in Parabolics as a distributor of Paul's springs but soon contacted a local Canadian spring manufacturer to make parabolic springs for him and started selling his own brand. Rumor has it Wise Owl may have switched to an offshore spring manufacturer.
UNDERSTAND THAT THIS IS RUMOR AND NOT FACT.
I'm not sure about British Steel, but I think they were persuaded to start manufacturing Parabolic springs by local UK wholesales who wanted to offer Parabolic springs they could source from a lower cost manufacturer. GUESS: Atlantic British buys a lot of stuff from Bearmach, so their springs are very likely made by British Steel. Given the price quoted for parabolics from Rover's North I would very tentatively guess they offer springs manufactured by British Steel as well. Mind you this is a W.A.G. and not based upon any data.
There may be more but these are the players that I am currently aware of. With my current limited knowledge of Parabolics, if I were to switch to parabolic springs I would use Heystee automotive springs.
That said I use sheets of ultra high density plastic between stock Land Rover spring leaves to reduce friction. The Ultra high density plastic was developed for industrial use where metal chutes slide against metal and has a low friction spec. I have more information about the plastic on a web page
http://www.expeditionlandrover.info/leafSprings.htm
Recently I had a chance to so some non-scientific side by side comparison testing. I have a friend with a Land Rover Dormobile that has newish parabolic springs attached. My friend and I drove his Dormobile on the highway and along a track in my back yard, about 8 acres of hillside. Then we drove my Land Rover Dormobile along the same route and compared notes. I am over sprung with one ton springs (Much stiffer than should be there considering my loaded vehicle weight). The one ton springs have been under my Dormobile since 1996 and and sheets of plastic since 1998.
We could not distinguish between the rides of our Dormobiles, except the one with Parabolic springs swayed noticeably a
little more on corners. I actually thought there would be more sway in the parabolics (Heystee Automotive parabolics) than there was based upon a much earlier experience with
early prototype parabolics made for Wise Owl (before Wise Owl started offering them for sale). I also thought the parabolics would have given a softer ride than my one ton springs with plastic sheets. Near as we could tell except on curves the ride was indistinguishable.
Parabolic spring development has come a long way from the too soft prototype parabolic springs I was first exposed to.
ADDED LATER: I forgot to mention that both Parabolic springs and semi elliptical springs with plastic sheets between the leaves have less resistance to flexing than stock unaltered springs so in both cases you should change to stiffer shocks.
