Let's talk about Defender rear coil options

[dmdigital]

I need to upgrade the rear coils on the Puma. This is because the upper (progressive) coils sag under load - e.g. when towing. Unladen the Defender is fine.

As I understand it the rear coils are a progressive 270-420 lbs/in (RKB101111).

I've decided not to go for polyairs or helper springs as I don't always have the weight in the back of the 110 and would like to keep a reasonable ride. Whilst the Polyairs would assist I still need to replace the exisiting coils as the upper 3 coils (lower rated) are the issue. I also don't want to lift the back with the suspension to higher than standard.

As I see it my options are to go for a heavier progressive or a straight liner replacement.

The HD LR springs (NRC6904/NRC6389) are a 330 lbs/in linear coil.
The OME 755's are also a linear (I believe) but only 270'ish lbs/in.
LRA can also supply a 270 lbs/in linear and a 320 lbs/in linear coil.

If the weekend's not to hot I was going to swap the King Springs KLRS-05's from the back of the Tdi to the Puma and see how they feel. These are a heavy coil and I suspect over 330 lbs/in. I can't find any publish rates for these springs.

The front end already has HD springs. I'm also replacing the LR shocks with something solid - and expensive - Koni Raids. So this will also assist the rear end as they should be good under hot conditions. They have a 70mm bore and I suspect will be unlikely to fade under normal track driving and make for a good ride on corrugations.

So I guess I have a few questions:
* If I replace the present 270-420 with a linear 270 I suspect this will be to weak for what I need. Is this correct?
* Assuming I need a heavier rate spring then is the 330 lbs/in LR going to be too harsh when the Puma is unloaded?
* Are there any options I should also consider?

[Captain_Rightfoot]

My car is booked in at the end of the month with MR to have polyairs fitted for exactly this reason (yes I know I could do it myself but time...time). I am going to fit my standard 110 springs in the hope that even with a couple of psi in the polyairs I will get a better ride around town - yet be able to pump them for when we are heavily laden.

I'm afraid I don't have the specs on the springs other than they aren't progressive and are about 10+% softer than standard.

I'll carry the defender standard springs on trips in case of breakages or polyair failures.

[dmdigital]

10% softer than which end of standard Since the standards are a progressive coil that's a little ambiguous I think as the upper part of the coil is significantly softer.

I'm trying to do all this without buying the wrong rate springs and then having to exchange them for others and pay lots and lots of freight.

[Blknight.aus]

I'd suggest you try the standard rear springs from the td5110. or the heavy duty items that were an option.

the standards should keep you out of trouble if you're not towing or loaded all that often and the HD's if your loaded or towing more often than not.

[weeds]

i was happy with my poly airs with standard springs....well till i was ripped one

around town no body roll (although you would have a sway bar fitted yes) fully loaded on my simpson trip along with plenty of other trips they worked a treat

i suspect i holed one running no air while off roading around a mates property

[weeds]

My car is booked in at the end of the month with MR to have polyairs fitted for exactly this reason (yes I know I could do it myself but time...time). I am going to fit my standard 110 springs in the hope that even with a couple of psi in the polyairs I will get a better ride around town - yet be able to pump them for when we are heavily laden.

I'll carry the defender standard springs on trips in case of breakages or polyair failures.

would you like a spare....used poly air as i think i will import the other major brand of airbag from the USA

[justinc]

Derek, what happened to the 130 idea? I am still contemplating this for mine for touring/ towing, and twin DeCarbons too.

JC

[JohnR]

I changed both my front and rear to a non progressive HD King Spring with a claimed lift of 50mm in reality from original I got around the 28mm lift from these. (But I do have a tonne of accessories )

Yes they are a little harsher than the original progressive springs but when loaded and towing they sit real nice. I think you are asking a lot to get a spring that is progressive but still an awsome towing and fully loaded spring.

For my two cents, when loaded and towing I drive rather sedately but obviously want minimal body role HD springs are good for this. But when I am not loaded or towing I usually drive like a mad man and therefore like the rather hard ride the springs give. Good shockies (which are my next up grade!) can make a firm ride very driveable without shudder or wheel chatter.

Give the tech line a call from King Springs I found them very helpfull.

Cheers,

[dmdigital]

I'd suggest you try the standard rear springs from the td5110. or the heavy duty items that were an option.

the standards should keep you out of trouble if you're not towing or loaded all that often and the HD's if your loaded or towing more often than not.

The standard rear springs that are in the Puma are the same as for the Td5 110's. The current ones have just worn out from my travels.

HD's are also the same as for the Td5, Tdi etc

Derek, what happened to the 130 idea? I am still contemplating this for mine for touring/ towing, and twin DeCarbons too.

JC

From what I can learn I think it will give too harsher ride. I'm still keeping the Polyair or 130 helpers as a last option at this point. I'd rather go a single coil if I can. I think one of the issues I have is the extortionate price (even in the UK) for the mounts for the helpers.

I changed both my front and rear to a non progressive HD King Spring with a claimed lift of 50mm in reality from original I got around the 28mm lift from these. (But I do have a tonne of accessories )...

Give the tech line a call from King Springs I found them very helpfull.

I was thinking of calling Kings to find out the rates of the KLRS-05's. Your's are probably the KRRS-05's. Both are a linear coil. I find the ride very harsh in the Tdi and have not been overly happy with the Kings. I suspect they are over 320 lbs/in in which case it will give me an idea of what the worst case is. So that's why I'm thinking I'll swap them over to the Puma for a day.

[Blknight.aus]

The standard rear springs that are in the Puma are the same as for the Td5 110's. The current ones have just worn out from my travels.

HD's are also the same as for the Td5, Tdi etc

how the snot did you manage that, Im still on my original springs and shocks and Im near as damnit to normal ride height after 170ish K Km....

mind you I started on HD springs.