Pajero springs for +50mm

[jalvesan]

My Pajero has the equivalent to 30.3in (265/70R16), it is all stock so far.

I am searching shops locally to ask the prices for rebuild the koni shocks.

BTW, the koni are only Heavy Track (not the Raid version).

Can you elaborate more in regard of the King's progressive spring sag when "loaded"?

"Normal" load (I don't carry much stuff when go offroad, remember it is a Short Wheel Base (SWB) and I don't pull anything behind the Pajero) or "heavy" load as you folks usually do with your 4wd's?

[Lost1]

Jalvesan, A progressive rate spring has varying diameter wire in the same spring. From memory some coils on the king spring are 18mm diameter. The thicker heavier rated section of the spring is 22mm diameter.

This variation in spring diameter is what allows the coil spring to cope with small bumps. When you hit a larger bump the lighter gauge coils will compress and the heavier gauge coils will begin to work.

When loading a car fitted with progressive rate springs you will notice the car will settle on its suspension as the lighter rated section of the coils compress under the weight of your load. This is not sag, as the spring is working as its design intended. The car will return to its original ride height once unloaded. As you don't carry the same weights we do in Australia I don't beleive this will be an issue.

Having said that IRS Pajero's will begin to wear the inside of the rear tyres if you are under sprung in the rear of the car. If you are running heavy occasionally you could use air bags to address this potential issue. Work out what equipment you will fit to your car (winch, front or rear bars, bash plates etc) then choose the appropriate spring (SD, MD, HD).

A car running linear rate springs of the same rating will usually ride slightly higher when loaded than progressive spring. If the Koni's can be rebuilt for a fair price I would recommend you buy King springs. Wait until you know what spring you are going to fit before rebuilding the Shock. Then you can have the shocks rebuilt to suit your springs. Good luck

[old Jack]

All springs "settle" from new between 5mm and 10mm with normal use even if they have been fully "scragged" at manufacture. However all springs will sag more if they are under sized for the weight they are regularly carrying particularly if the coil is subject to high extension and compression cycles as in a 4wd that does serious off-road work requiring full articulation at full or near to full loads.

Linear rate coils have the same about of spring rate during the complete range of travel so with a spring rate of 20kg per mm, the first mm of travel it takes 20kg of weight, for the 2nd mm it takes 40kg, the 3rd mm takes 60kg and for every mm extra compression it requires and extra 20kg of weight. These are the cheapest coils to manufacture and are the most common after market coil.

Progressive Rates Coil Springs come in 3 varieties;
1. The most common is the same wire diameter for the complete length of the coil but the gap between the coils (pitch) is varied evenly and incrementally getting larger from one end of the spring to the other. The sections of the coils that close up first provide the initial and softer compression and then these coils winds close up and become inactive and the remainder of the coil takes over. Compared to the linear rate coil above at 20kg/mm a progressive rate coil of tis type may have spring rates from 15kg per mm to 25kg per mm. The results is these will be more comfortable when lightly loaded and carry heavier loads better. these are the cheapest/easiest of the progressive rate coils to make and can be the same price or slightly more than linear rate coils. Great for empty to full loads and every thing in between at a reasonable price.
2. The 2nd most common progressive rate coils is a staged coil, it uses the same wire as above but rather than an even and incremental increase in the gap between the coil winds it may have 15mm between the first 4 winds of a 7 wind coil and 20mm between the last 3 winds. These springs are more difficult to design and manufacture, and getting the "stages" in the correct position for the weight is difficult. Ideally suited for empty or full loads and not 1/2 loads.
3. The most complex and most expensive coil to manufacture as it is the variable wire diameter wire and variable wind pitch, these coils give the best ride and reduced rebound forces of all coils and they are not very common as off the shelf items and are normally custom made. Expect to pay about 50% more for these coils but they are worth it if they are available. Kings spring are the only company I know of in Australia that have the equipment to make these coils. For example sake they could range from 12kg per mm to 30kg per mm compared to all of the above mentioned coil springs.

Designing and manufacturing coils for live axle vehicles is much simpler and easier compared to IFS (Independent Front Suspension) and IRS (Independent Rear Suspension), on IFS/IRS the coil is mounted approximately half way between the centre of the wheel rim and the pivot point of the suspension so the spring has to be twice as strong in spring rate to carry the weight of the vehicle. Coils for IFS are even harder as not only do they need to carry double the weight but also there is normally a space constraint so the coils are smaller diameter. Making a progressive/variable rate coil for IFS is very difficult because not only does the wire diameter and coil pitch vary but also the coil diameter, there a very complex calculations required in the design of these coils and the equipment to make them is very specialised. Only King Springs have this equipment (in Australia) to my knowledge and they will make custom coils at a price. However Terrain Tamer do offer these design of coils, marketed as "Smart Coils" for a number of vehicles at a fair price of about $350 per pair, and I have been told they are made by Kings Springs.

Unless you are a driving enthusiast or travel very heavy and over very rough terrain then an off the shelf coil will do the job nicely if the correct coil is selected. Doing custom design coils is an expensive and time consuming exercise that is not for the faint hearted, those on a budget or with average mechanical knowledge.

OJ.

[nj swb]

Thanks OJ; I was half aware of some of the above, so you've fliled in some gaps and taught me some completely new stuff too.

While I've been generally happy with ride comfort and handling from my OME suspension it did prove to have the articulation of a skate board, which has had me wondering if better springs could provide more stability in the more extreme terrain. That's why I jumped at Steve's Kings - I'm hoping the extra free length of the variable spring will extend the droop a little more while articulating, help to keep the wheel on the ground a little longer.

[old Jack]

Thanks OJ; I was half aware of some of the above, so you've fliled in some gaps and taught me some completely new stuff too.

While I've been generally happy with ride comfort and handling from my OME suspension it did prove to have the articulation of a skate board, which has had me wondering if better springs could provide more stability in the more extreme terrain. That's why I jumped at Steve's Kings - I'm hoping the extra free length of the variable spring will extend the droop a little more while articulating, help to keep the wheel on the ground a little longer.

No problems NJ. If I am available when you want to change them over and if you are doing it yourself I might just make the pilgrimage across town, drink your beer and watch you change them over, also provide some friendly advice retrospectively!

OJ.

[nj swb]

... drink your beer and watch you change them over, also provide some friendly advice retrospectively!

OJ.

Coopers Mild, or would you insist that I buy something Light?

[old Jack]

Coopers Mild, or would you insist that I buy something Light?

If someone else is paying and as long as it is Coopers then Sparkling, Pale, Mid or Light does not matter. Light is cheaper but requires more before I need a sleep!

OJ.

[jalvesan]

My Friends,

you are doing public service here.

Many, many THANKS!

I am leaning towards Kings KCFR-34HD for the front and KCRS-35 for the rear.

Koni Heavy track for the shocks.

Again, thanks to all the contributors to this thread.

[Amok]

What's everyone's thoughts on fitment places?

I am getting an ARB bullbar soon and since they are an expensive place to buy from, I thought I'd shop around for springs/shocks afterwards. I'll see how the standard suspension holds up before deciding (just bullbar, no winch, no dual batteries).

I spose I could just buy a kit from Bushskinz for example and fit myself but don't really have the time or workspace at the moment.

[smwhiskey]

Amok

Something to consider. With me being a mechanical numpty, I've had ARB do a fair bit of work on my Pajero and havn't had a problem with the quality of the product or the workmanship done. (can't say the same for every place I've taken the Pajero). When I did the build I got plenty of good advice about the suspension and the dual battery system.

Yes they may be more expensive than other places but to me its been worth it.

Simon

[Amok]

Hi Simon, yes fair point and I completely agree. fortunately i am a qualified mechanic so i can do most things myself. Its finding the time and space to do it that is hard, as I'm now an office type dude and have the worlds smallest carspace.

[jalvesan]

With the bad experience I got with the OME springs, I am now seriously considering the use of spacers to increase the height of my SWB Pajero.

[BlackAngels]

In the last month I completed a +50mm lift in my 05 NP GLX Pajero and I noticed a physical difference in height for the rear springs. I used Lovells medium duty springs front and rear and the Bilsteins shocks. Although I was told I would get a 50mm lift allround what I found was correct for the front but got an increase of about 70 - 80mm in the rear
(I don't carry any load normally).

One other an more important thing to consider regarding lift kits, is that for my Pajero and many others there is a problem with a vibration being induced in the rear of the vehicle. I have been through many possible reasons and have also removed the vibration blocks off both the transmission as well as the one mounted on the diff, this has made only a small difference. The best and most probable cause will be the rear CV shafts with there increased change of angle causing the vibration. Once the lift kit has been fitted and "if" you are unfortunate enough to have this problem then try putting 100-200kgs of sand bags in the back(assuming your not carrying any load already) as this will help to realign the CV's back to there original position and you will then have a better understanding as to what may have caused the problem.

[C&S Evo7]

the position change of the bearings inside the cv can cause the vibration , ive seen this numerous times with Honda s2000 track cars ive been involved with, when they are run low the cvs change position and can vibrate, we fit 8mm spacers between the diff and shafts to allow for the realignment , it works a treat, not sure if it would work the opposite way for a lift , but i dont see why not, the other thing to watch is the increase in rear toe which can wear the tyres pretty quickly.

[Waitforme]

I have Lovells with Bilstein shocks on my LWB NM and the ride is veryy compliant. Not harsh.