Outer Limits 4x4 Board

I am thinking of changing my front stock set up in BOB to a 3 link + panhard. 2 lowers and 1 fairly centred upper.

I have been reading on Pirate about the many benefits off-road, but I am mainly concerned about the on road handling - for a change

To me the stock set up has been awesome and I am a great believer in the inherent superiority of the Rover geometry compared to Toyo, and of course, Nissan front ends - I mean, really...the bricks in my house have more flex than a Patrol front end.

But in the quest to drive trails with ever increasing levels of difficulty, I am starting to think that a custom 3 link and panhard is the go.

May I please have the considered thoughts of the Land Rover forum to help mould my decision? Right now the stock set up is serving me just fine...but that is right now.

I know that I can search and find all the answers I need, but what I am searching for is that little voice..you know the one? The one that's like a conscious? The one that is there to remind you that you may get caught doing something wrong?...Well when it comes to modding BOB - I dont hear that voice. Thats why BOB looks like this...





And not like this...

COILOVERS


And really it does not matter what opinions are you know you will just do it anyways. You know you want to so Just order the coilovers and get on with it.























And you might aswell order some 3/4x3/4 cromo hymes from the states Oh and some t7 alloy for links and Fark double it and we will do the rear aswell (after we cut the rear off that is)

coilovers bitch!!! like nottie says, follow frankenstein? the older purple fenderish rover on mogs from pirate, sweeet rig with bucket loads!!!!!


hmm me wants to too!!

thought about SG three link but alot of mixed reviews, bu later ones seem ok....

Sam you should try driving your for once instead of thinking of mods to do.

Where are you going to put the upper central link?
Most rovers have an engine and gearbox in the way.

Where there is a will there is a way.
They dont have to run straight either.

After being stuffed around by Safari Guard for a couple of months waiting for delivery we made up our own 3 link + panhard.

The two lower arms use the original chassis mounts on the rear of the arm and the rear mounts on the diff housing for the front of the arm.

We made the upper arm with joints both ends and mounted the rear of the arm inside the chassis rail on the passenger side and made up some mounts for the front of the arm that we mounted on the passenger side of the diff parallel to the rear mount.

The only issue was modifying the extractors to clear the new upper arm.

Drives like a boat on the road, but lots of travel offroad.

Just my personal choice, but I wouldn't do it for a vehicle regularly driven on the road.

Hi, I have a 91 rangie with a S G three link front end, the on road handling is not as good as factory but i used a good adjustable shock to firm it up on road, but off road it is as good as the rear end, i have shocks 830 extended front & rear and its not enough, but where do u stop with travel. Mines nice and balanced. Cheers Gary

i think a well designed 3 link + panhard can be set up very well.... guys are running them on the KOH rigs and they do some speed.....

if you are going to the trouble of fabing all that stuff i would not restrict yourself to the stock chassis mounts...although they may be fine...but making your mounts further back may have some advantages.....

i would also read the coilover bible, that may give you some insight to some design criteria???

guys i would ask are: strange rover, bush 65, triaged, bigger valves, and bill larman if you can find him.

i think what will be very important is the panhard to drag link relation...as it is in stock form also.... you will be able to design in your front axle roll axis, your rolll center will be determind by your panhard. but you will probably just keep the existing Pan & draglink... which should be fine...

how does it handle now? one thing i have thought about when lifting rovers on the springs is the front axle roll center gets higher, while the rear does not....this then changes the vehicle roll axis.... but it doesnt seem to effect much on my 2-3 inch lift 110....massive i know lol.

PLEASE NOTE: im just a web wheeler with no engineering back ground....just enough information to make me dangerous!

Serg

I do know that within time micks car (BOB) will no longer take part in the bitumen wars of everyday driving. It will be driven round on a truck like the royal queen herself.
If i have anything to do with it ( I will ) It will loose most body parts and a whole lot of chassis and become the truggy it so longs to be.

uninformed wrote:i think a well designed 3 link + panhard can be set up very well.... guys are running them on the KOH rigs and they do some speed.....

if you are going to the trouble of fabing all that stuff i would not restrict yourself to the stock chassis mounts...although they may be fine...but making your mounts further back may have some advantages.....

i would also read the coilover bible, that may give you some insight to some design criteria???

guys i would ask are: strange rover, bush 65, triaged, bigger valves, and bill larman if you can find him.

i think what will be very important is the panhard to drag link relation...as it is in stock form also.... you will be able to design in your front axle roll axis, your rolll center will be determind by your panhard. but you will probably just keep the existing Pan & draglink... which should be fine...

how does it handle now? one thing i have thought about when lifting rovers on the springs is the front axle roll center gets higher, while the rear does not....this then changes the vehicle roll axis.... but it doesnt seem to effect much on my 2-3 inch lift 110....massive i know lol.

PLEASE NOTE: im just a web wheeler with no engineering back ground....just enough information to make me dangerous!

Serg

All god point there Serg.

Mick reads the coilover bible to his daughter every night when she goes to bed,

No need to ask Sam about the set up as Mick talks to Chuck (Sams partner in crime). And he is as cluey as Sam. But Sams input is allways very informative and educational. (even if you have to re read it to fully understand)
I think with alot of the trucks on pirate with this sort of set up it is the coilover set up that keeps them stable to an extent.

3 inch on a 110 in my opinion is about right. (just cut the guards and tube the front to fit 38s Trust me i know)

something else i have been thinking about regarding the on road characteristics....

when stock the front axle roll axis is about 0-1 degree roll oversteer...the rear about 3-5 degrees roll oversteer.... now with your lift they will be alot more than that (percentile wise). if you dial the front back down to say 0 degrees with your new 3 link i wonder how that will play out with the rear being about 10-15 degrees????

also that in conjunction with the vehicle roll axis being changed as the front has risen and the rear has not....

i think that maybe the constant 4wd helps a bit... but when have asked on pirate i never got any responses.....

just thinking out loud

Now thats the question Strange should chyme in to answer Serg.

I have just re read the 4 link 4 dummies thread on pirate and my head really hurts.

more thinking...........

if the front axle roll center is higher because of the lift (panhard disecting chassis center line) im thinking the "roll stiffness" will also increase to some degree...

am i correct in thinking the higher the roll center the more the body has to move during articulation... so it would give some restrcition to roll and be more stable on side slopes compared to a low roll center??

be good to hear some more discussion on this

Serg

uninformed wrote:more thinking...........

if the front axle roll center is higher because of the lift (panhard disecting chassis center line) im thinking the "roll stiffness" will also increase to some degree...

am i correct in thinking the higher the roll center the more the body has to move during articulation... so it would give some restrcition to roll and be more stable on side slopes compared to a low roll center??

be good to hear some more discussion on this

Serg

Roll stiffness is only influenced by springs and bushings. A 3 link has far less roll stiffness than a radius arm front end so will body roll much easier.
Because the roll centres are moving further from the centre of gravity, you're going to get more body roll.
The rest sounds about right.

KiwiBacon wrote:

uninformed wrote:more thinking...........

if the front axle roll center is higher because of the lift (panhard disecting chassis center line) im thinking the "roll stiffness" will also increase to some degree...

am i correct in thinking the higher the roll center the more the body has to move during articulation... so it would give some restrcition to roll and be more stable on side slopes compared to a low roll center??

be good to hear some more discussion on this

Serg

Roll stiffness is only influenced by springs and bushings. A 3 link has far less roll stiffness than a radius arm front end so will body roll much easier.
Because the roll centres are moving further from the centre of gravity, you're going to get more body roll.
The rest sounds about right.

i was just thinking that maybe the higher roll center would make the body roll a little less than a low roll center with the same 3 link set up..... maybe not enough to measure though through the seat of your pants so to speak....

i was aware about the differences between RA and there stiffness and 3 links..


Serg

uninformed wrote: i was just thinking that maybe the higher roll center would make the body roll a little less than a low roll center with the same 3 link set up..... maybe not enough to measure though through the seat of your pants so to speak....

i was aware about the differences between RA and there stiffness and 3 links..


Serg

The 3 link in the rear has the roll centre right on the ball-joint. So bigger wheels will raise it, but suspension lift won't.
On the front it's again down to suspension lift, but with the panhard it raises at half the rate you lift the body.

When suspension is lifted, the CofG becomes further above the roll centre, even though the front roll centre rises. The CofG moves vertically about as far as the chassis end of the panhard, but the roll center only half of this change.

If the roll centre is moved closer to the height of CofG due to relocating the axle end of the panhard, then body roll will be reduced. But this is not practical with the need to keep panhard and draglink parallel.

Edit: Sorry, I just read Dougal's post after writing that, and seen I have repeated what he said.

My bushie has a 3 link front suspension that was originally made by Bill Larman for someone else that I bought the front and rear axles from.

The upper (third) link is offset to the left of the engine sump. The cross member under the gearbox was modified and uses a stock chassis mount for a rear trailing arm.

The eccentric position of the upper third link can be used to counteract torque roll, which is an advantage when your left front wheel is high on a rock or ledge and application of power will roll you further to the right. Which side to offset it depends on its slope from chassis end to axle end. The optimum offset is in proportion to the diff ratio.

IMHO use a swaybar on the road with disconnects for off road.

Bush65 wrote:My bushie has a 3 link front suspension that was originally made by Bill Larman for someone else that I bought the front and rear axles from.

The upper (third) link is offset to the left of the engine sump. The cross member under the gearbox was modified and uses a stock chassis mount for a rear trailing arm.

The eccentric position of the upper third link can be used to counteract torque roll, which is an advantage when your left front wheel is high on a rock or ledge and application of power will roll you further to the right. Which side to offset it depends on its slope from chassis end to axle end. The optimum offset is in proportion to the diff ratio.

IMHO use a swaybar on the road with disconnects for off road.

Can you post some pictures of this John?
It sounds very interesting.

KiwiBacon wrote:

uninformed wrote: i was just thinking that maybe the higher roll center would make the body roll a little less than a low roll center with the same 3 link set up..... maybe not enough to measure though through the seat of your pants so to speak....

i was aware about the differences between RA and there stiffness and 3 links..


Serg

The 3 link in the rear has the roll centre right on the ball-joint. So bigger wheels will raise it, but suspension lift won't.
On the front it's again down to suspension lift, but with the panhard it raises at half the rate you lift the body.

thanks for the replys,

i did already say this in my second post, but i get where your coming from by John's post.

thanks,
Serg

KiwiBacon wrote:

Bush65 wrote:My bushie has a 3 link front suspension that was originally made by Bill Larman for someone else that I bought the front and rear axles from.

The upper (third) link is offset to the left of the engine sump. The cross member under the gearbox was modified and uses a stock chassis mount for a rear trailing arm.

The eccentric position of the upper third link can be used to counteract torque roll, which is an advantage when your left front wheel is high on a rock or ledge and application of power will roll you further to the right. Which side to offset it depends on its slope from chassis end to axle end. The optimum offset is in proportion to the diff ratio.

IMHO use a swaybar on the road with disconnects for off road.

Can you post some pictures of this John?
It sounds very interesting.

The crossmember and 3rd link were removed when I pulled the engine and gearbox to swap into my rangie.

I took some pics that show the 3rd link mounts on the axle and crossmember.

The 3rd link is the same as a rear trailing arm. The 2 lower links use the normal chassis mount and the bush at the axle end is the same as the axle end of the rear trailing arms.

Edit: Because worst case load in upper link is tension, the chassis mount is bolted to the rear of the bracket.



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Thanks for posting that pic John. Is that a modified Defender Xmember?

Slunnie wrote:Thanks for posting that pic John. Is that a modified Defender Xmember?

I don't know what it came from - the axles came with that cross member, links, and some misc brackets.

It looks the same as a rangie cross member and fitted into the rangie chassis without any changes.

BTW, I made the scollop for driveshaft clearance, the rest was done by Bill.

BTW, in the bottom left corner of this pic you can see part of the spring seat, and on the rear of the axle tube, the upper part of the bracket for left lower link.

Hi John,

Are they volvo axles? the square tubes look familiar?

Cheers
G

Yes.