Parabolic springs...

[DaveS3]

Parabolic springs..Where can i get them in Vic????

I know of one place but are there any others???

Also, Has anyone used these? Are they worth it?

Will be fabbing custom shock mounts, longer shackes as well

Thanks!
Dave

[modman]

you tried anthony at british 4x4?
if you make custom spring hangers then use hilux parabolics, they are longer therefore more flex
david
(sorry enforcer maybe)

[ISUZUROVER]

From what I have seen (and researched) parabolics give a smoother ride, and more "coil like" travel over a short distance, but due to the thickness of the leaves, the overall wheel travel is no better or even worse than properly designed semi elliptic springs. So it depends on what you want most - comfort or wheel travel.

I designed my own springs based on the original leaf semi elliptic leaf packs - I now get about 15" of front and rear travel (30" total) with std military shocks on the front and RR shocks on the rear and stock shock mount and spring locations.

[DaveS3]

you tried anthony at british 4x4?
if you make custom spring hangers then use hilux parabolics, they are longer therefore more flex
david
(sorry enforcer maybe)

Thats who i knew had them!

[DaveS3]

Ben,

Can you post some info on how you designed your leaves...?

i want more travel, and the ride wont get any worse, so i dont really care about that!

The truck gets reasonable travel know, but the shocks limit it terribly, and i thought that parabolics and longer shocks would make a difference, but if there are more options like modded spings, i would like to find out about this and do this mod once, properly.

Dave

[ISUZUROVER]

Ben,

Can you post some info on how you designed your leaves...?

i want more travel, and the ride wont get any worse, so i dont really care about that!

The truck gets reasonable travel know, but the shocks limit it terribly, and i thought that parabolics and longer shocks would make a difference, but if there are more options like modded spings, i would like to find out about this and do this mod once, properly.

Dave

Do you have a LWB or SWB SIII? Civilian or military?

Front.
The best front springs are the std 9leaf SWB petrol springs (200lb/in) - these have one 4.4mm main leaf and 8 4.2mm leaves - it is hard to find a good second hand set. They will work on all LR's except a 3.9 ISUZU. If you have these springs just cut a taper in the leaves, smooth up the edges and that is all. I didn't have these so I bought after market SWB petrol spings that have 9x5mm leaves so the rate is 315lb/in!!! - I removed 3 leaves (so now 6), tapered and smoothed the edges and had them reset to about 11" free camber (drivers) and 10.5" passenger. If you have a military LR, remove the bump stop spacer but retain the std shock. If you have a civilian LR, you can usually get a lot more up-travel than the bump stop will allow. I know people who have cut the bump stop in half, but you can also relocate the shock mount higher and fit longer shocks.

Rear.
For a SWB - again the std factory leaves are best - should be 11x4.4 (longer leaves have a lower spring rate) with a rate of 160lb/in. Again if you have these, taper the leaves.
For a LWB - you want a rate of about 270lb/in. I had std military 8x7.1mm springs, which are 400lb/in. (S3 9x7.1mm are 500lb/in!!!). I removed 3 leaves (now 5), cut the rest down to an even spacing and tapered them. And had them reset to about 14" drivers side and 12" passenger. All it cost me was $60 a pair to reset - make sure they temper them after resetting. They will settle a bit after you have them on the truck, that is why the free camber is so high. You could go a bit softer but 270lb/in still lets me carry a decent load as well.
For a military truck, leave the rear bump stop spacer in and fit Range Rover rear shocks. For a civilian, RR shocks would work as well but you need to raise the shock mount (and have to cut a hole in the floor for space).

You will get increased on road comfort with this setup, and more body roll, but the truck is just as stable when cornering, and you get used to the body roll. If you have an engineering background, grab a book called the "leaf spring design manual" by the SAE. It is what I used. But if you just follow the steps above you won't need it.

[DaveS3]

thanks Ben...

I have a SWB civillian, but i think with some military stuff on it!

Have you looked at changing to other model springs???

[ISUZUROVER]

There are quite a few guys in the US that have fitted longer front springs (Chevy usually) - have a search on Pirate.

Longer front springs will help, but decrease your approach angle unless you are fitting biger wheels at the same time. The back springs on a Landie are long enough.

Most of the "off the shelf" springs available are too stiff. I rang around a lot of spring places 5 years ago when I did mine and they all tried to sell me heavy duty springs.

If your welding is OK it would be worth fitting military hangers and shackles and longer shocks.

[DaveS3]

i plan on fitting military shackles, but not lowering the hanger just yet.

I will put longer shocks on and extend the mounts, and probably dish the front crossmember, look at shafts as well.

All in time i guess...just trying to do some research now as i get loooooong uni holidays soon!

Thanks
Dave

[ISUZUROVER]

Don't put military hangers on the front without the extended dumb irons. Your front propshaft and uni's won't like it.

Check to se that you have 9x4.2-4.4mm front springs (not 9x5mm), and 11x4.4 (not 11x5mm) rear springs. If you have heavier springs that will be the biggest thing that effects your travel.

[Slunnie]

Ben, what are the dumb irons?

[ISUZUROVER]

Ben, what are the dumb irons?

Dumb irons are the official name for the front spring hangers.

[LandyLad]

Thanks for the reply ! I've read your thread and it did help somewhat. A friend of mine put me on to a site that may be of some interest to you ! Just do a Google search for ( gon2far ) It is a company that specialises in Landrover suspension. Very impressive!!!!

thanks again ! Chad.

[DaveS3]

yeh....already know about that one!

The guy who makes it is on PBB, and said he was going to update it in a few months!

Look at pirate now, as there is a S2a lightweight with volvo's and the gon2far kit, flexes very very nicely!

Dave

[Slunnie]

Ben,

I've got a SeriesII 109 with an aluminium tray, V8 and ZF/LT230 and hoping to fit Petrol Shorty 200lb/in 9 leaf springs to the front and the 166lb/in 11 leaf rear springs. I'm looking for articulation, more so than load carrying capacity.

With the excellent spring guide above, when the springs are reset to your specifications, how does this alter the ride height? I'm assuming by the free lengths that it brings the front up by 5" and the rear by about 6" (excluding weight differences). Also, with this much free camber, I'm assuming that they need to be running the military shackles front and rear.

[ISUZUROVER]

Ben,

I've got a SeriesII 109 with an aluminium tray, V8 and ZF/LT230 and hoping to fit Petrol Shorty 200lb/in 9 leaf springs to the front and the 166lb/in 11 leaf rear springs. I'm looking for articulation, more so than load carrying capacity.

With the excellent spring guide above, when the springs are reset to your specifications, how does this alter the ride height? I'm assuming by the free lengths that it brings the front up by 5" and the rear by about 6" (excluding weight differences). Also, with this much free camber, I'm assuming that they need to be running the military shackles front and rear.

Hi Slunnie,

My springs sat 1-2" higher. Military shacles not necessary.

However - you have a lighter engine. Can you get the weights of each corner? And estimate the static camber you want? If so, I can do the calcs for your springs.

[Slunnie]

Ben,

I've got a SeriesII 109 with an aluminium tray, V8 and ZF/LT230 and hoping to fit Petrol Shorty 200lb/in 9 leaf springs to the front and the 166lb/in 11 leaf rear springs. I'm looking for articulation, more so than load carrying capacity.

With the excellent spring guide above, when the springs are reset to your specifications, how does this alter the ride height? I'm assuming by the free lengths that it brings the front up by 5" and the rear by about 6" (excluding weight differences). Also, with this much free camber, I'm assuming that they need to be running the military shackles front and rear.

Hi Slunnie,

My springs sat 1-2" higher. Military shacles not necessary.

However - you have a lighter engine. Can you get the weights of each corner? And estimate the static camber you want? If so, I can do the calcs for your springs.

Thanks for this Ben.

Is a V8/ZF/LT230 lighter than the 4banger setup?

I'm really not sure what it would weigh in that case.... perhaps an option is to also pull a leaf from the front then.

The car is at work at the moment (workshop) though I would like something between a true 2-3" static lift and full articulation. I don't want to go over 3" lift though to keep overall lift at 6". The Xmember is about to be notched to allow propshaft clearance.

[ISUZUROVER]

Ben,

I've got a SeriesII 109 with an aluminium tray, V8 and ZF/LT230 and hoping to fit Petrol Shorty 200lb/in 9 leaf springs to the front and the 166lb/in 11 leaf rear springs. I'm looking for articulation, more so than load carrying capacity.

With the excellent spring guide above, when the springs are reset to your specifications, how does this alter the ride height? I'm assuming by the free lengths that it brings the front up by 5" and the rear by about 6" (excluding weight differences). Also, with this much free camber, I'm assuming that they need to be running the military shackles front and rear.

Hi Slunnie,

My springs sat 1-2" higher. Military shacles not necessary.

However - you have a lighter engine. Can you get the weights of each corner? And estimate the static camber you want? If so, I can do the calcs for your springs.

Thanks for this Ben.

Is a V8/ZF/LT230 lighter than the 4banger setup?

I'm really not sure what it would weigh in that case.... perhaps an option is to also pull a leaf from the front then.

The car is at work at the moment (workshop) though I would like something between a true 2-3" static lift and full articulation. I don't want to go over 3" lift though to keep overall lift at 6". The Xmember is about to be notched to allow propshaft clearance.

The 4-pot is quite heavy, but to be honest I am not sure. I seem to remember the Stage 1 has a lighter front end...

You will get the best travel when the springs are almost flat at static loaded camber (ride height), so - if possible, it would be better to run military shackles (and hangers if possible), and flatter springs.

So I take it you can't weigh each corner? I can give you my best guess at spring cambers next week then if that is the case.

the SWB rears will be interesting. My rears are 250lb/in or so. With 1.1 tonne on the back the axle is a few mm off the bump stops. SWB springs will need a LOT of free camber, but should be doable if you have a reallyt light rear end. You will be the first to my knowledge.

[Slunnie]

The 4-pot is quite heavy, but to be honest I am not sure. I seem to remember the Stage 1 has a lighter front end...

You will get the best travel when the springs are almost flat at static loaded camber (ride height), so - if possible, it would be better to run military shackles (and hangers if possible), and flatter springs.

So I take it you can't weigh each corner? I can give you my best guess at spring cambers next week then if that is the case.

the SWB rears will be interesting. My rears are 250lb/in or so. With 1.1 tonne on the back the axle is a few mm off the bump stops. SWB springs will need a LOT of free camber, but should be doable if you have a reallyt light rear end. You will be the first to my knowledge.

Thanks for this Ben, I appreciate the effort you're putting in here.

I cant at the moment because I've just stripped it while I change the engine and gearbox. Its currently a chassis and tray with axles. IT might be a better idea then to wait until I can put it on the weighbridge and get a more accurate set of figures to work with. The rear end is quite literally just an aluminium tray though so probably weighs next to nothing. I guess my other concern is that if I used more free camber than what you have used, then the shackles wont go on or they will invert. If its not going to work though I can also weigh down the rear easily enough with tube and a roll bar and then run a spring setup which is similar to yours.

I'm not sure if the hangers are military. Actually I suspect they are civilian hangers and military shackles.

[ISUZUROVER]

There shouldn't be any worry with inversion - that seems to be just a toyota problem .

I had to use a hi-lift jack and a chain to flatten my front springs so I could bolt up the shackles. Never had a problem with inversion though.

Looks like civvie hangers and mil shackles - as you say.

[RangingRover]

There shouldn't be any worry with inversion - that seems to be just a toyota problem

Happens to Suzuki's as well, when they lose a tyre on the step out of a boghole, and get yanked out by a Rangie.....

[ISUZUROVER]

There shouldn't be any worry with inversion - that seems to be just a toyota problem

Happens to Suzuki's as well, when they lose a tyre on the step out of a boghole, and get yanked out by a Rangie.....

Interesting... Maybe having the shackles at the rear (on a landie) helps...?

At full droop on the front, my shackles are pointing at the axle housing, but as mentioned, they have never inverted.

Slunnie - if you have to go through engineering, and you will be running big wheels, it might be worth considering running rear springs up front as well.

[Slunnie]

There shouldn't be any worry with inversion - that seems to be just a toyota problem

Happens to Suzuki's as well, when they lose a tyre on the step out of a boghole, and get yanked out by a Rangie.....

Interesting... Maybe having the shackles at the rear (on a landie) helps...?

At full droop on the front, my shackles are pointing at the axle housing, but as mentioned, they have never inverted.

Slunnie - if you have to go through engineering, and you will be running big wheels, it might be worth considering running rear springs up front as well.

I had a think about this for a bit and agree with you, but if I start to reengineer the suspension then I'll more than likely link it all up instead to cure wrap problems and it lets me set the geometry. Its a weekends work to do the rear for me and I have a linked axle ready to put in, but the front is a bit more mucking around which I'm not yet ready to do. The front leaf spring length I think is a real limiting factor in these (and I tend to think that you've gotten as much out of this setup as whats going to come), but I also think that the cross member under the front prop is a limiting factor also. I'm currently putting a recess into the Xmember to give more shaft clearance for drop travel, so hopefully that will allow more suspension options a little later down the track also.... without having to pull the engine again.

[ISUZUROVER]

There shouldn't be any worry with inversion - that seems to be just a toyota problem

Happens to Suzuki's as well, when they lose a tyre on the step out of a boghole, and get yanked out by a Rangie.....

Interesting... Maybe having the shackles at the rear (on a landie) helps...?

At full droop on the front, my shackles are pointing at the axle housing, but as mentioned, they have never inverted.

Slunnie - if you have to go through engineering, and you will be running big wheels, it might be worth considering running rear springs up front as well.

I had a think about this for a bit and agree with you, but if I start to reengineer the suspension then I'll more than likely link it all up instead to cure wrap problems and it lets me set the geometry. Its a weekends work to do the rear for me and I have a linked axle ready to put in, but the front is a bit more mucking around which I'm not yet ready to do. The front leaf spring length I think is a real limiting factor in these (and I tend to think that you've gotten as much out of this setup as whats going to come), but I also think that the cross member under the front prop is a limiting factor also. I'm currently putting a recess into the Xmember to give more shaft clearance for drop travel, so hopefully that will allow more suspension options a little later down the track also.... without having to pull the engine again.

I am happy with my setup, and I think I have about 90% out of it. A link between the axle and the bumper area will apparently solve any axle tramp issues (not that these are major) - but I will probably try this in future. I could possibly also do with longer shocks and relocated upper mounts (but I have a mil chassis with the bump stop spacer removed). I have about 15" of travel front and rear. I could run softer rears like you are planning, but I like the balanced travel and ability to still carry a load.

However - if I had a SWB/MWB, and was running 36" or larger wheels, I would probably chop the front outriggers and move them forward. A few extra " of wheelbase in exchange for longer springs. This would also make the prop angle a bit better. FYI - military landies have a scalloped/clearanced front crossmember. I have never had a problem with the front, but the rear scrapes the crossmember hole on RHR full droop.