I know its gettin boring but.........

[boggo]

Sorry,but can anyone tell me(algebra aint a strong point for me),if a vehicle,lets just say a defender for arguments sake,which apparently has a front spring rate of 155/215lbs,was forced to carry an extra 60kg,what the new rates would be in order to retain the original specs(?)?? Or conversely,does anyone know what an unladen stock td5 defender weighs at its front axle??(does any of that make sense) If anyone can help,it would be greatly appreciated.:D

[PhilipA]

There is no set answer for your question.
For example a spring with the same rate but 25CM longer may do it.
Or a heavier spring 12 cm longer or even the same length.
Dual rate complicates it even more, because probably the low rate bit would currently be in bind so not effective.
its a case of suck it and see when you start making mods.
Regards Philip A

[disconut]

"conversely,does anyone know what an unladen stock td5 defender weighs at its front axle??"

A stock defender is a 90,110,130, hard top, soft top, auto, manual, V8, TD5, 300TDi etc. Pick a weight.

Trev.

[dullbird]

errrrrrrrrrrrrrrrr 20lbs

did i win:)


:rolleyes: well you did say pick a weight

[disconut]

errrrrrrrrrrrrrrrr 20lbs

did i win:)


:rolleyes: well you did say pick a weight

And the winner is............................................?

Trev.

[Slunnie]

With that extra weight the springs may also continue to sag.

[boggo]

A 110 Td5 wagon.I thought there would be a more precise way than the suck it and see method.Is that how land rover come up with their figures in the first place?

[disconut]

Go to your friendly weigh bridge and get the front end weighed. Then talk to a spring manufacturer. Weigh the rear also for later reference.

Trev.

[DEFENDERZOOK]

errrrrrrrrrrrrrrrr 20lbs

did i win:)


:rolleyes: well you did say pick a weight


shouldnt that be 22 stone.....?

[rick130]

OK, a stock Oz spec pre '02 Defender had a spring rate of 225 lb/in. Now I'm rounding off numbers here, but lets assume it has a free length of 16" and a compressed length (on a very level floor) of 10" (I pulled that one out of my ;) ), disregarding the small amount of reduced rate from the closed and ground ends, we have a weight of 1350lb on that corner. Now lets assume the car is 'square' (equal weight on all four corners, which it won't be) we have 2700lb across the front axle. If we add a winch which weighs 100lb/45.5kg which adds 50lb on each corner, each spring will deflect just under 1/4". (50lb divided by 225lb/in = 0.22" ) So, to retain ride height you would add a 1/4" packer, or have a new spring made 1/4" longer at the same rate, or get a spring made 230lb/in that deflects 6.08" under the new load of 1400lb to retain ride height. (bear in mind the best race springs in the world, Eibach and Hyperco are only guaranteed to within +,- 2% of quoted rate ;) )

Does that help ?

[disconut]

Wow! :eek: There's something in that Hunter Valley water thats doing you some good! :rolleyes:

Trev.

[boggo]

Thanks rick130,I knew there had to be some sort of science behind it.Its all slowly coming together.Cheers big ears!!:D