3 Link front ends

[will_warne]

Will.Unless you were playing with a series 2 Disco why would you feel the need to over complicate the rear end by replacing the excellant A frame plus two lowers with hockey sticks and an X link ?

Simon. although I have built two vehicles with Watts link front ends, and the bump steer issue was nowhere near as serious as some think, these and upper wishbone 3 link style front ends are probably really more suited to full hydro steering.

Bill.

Bill, no DII axles at the moment and I am staying A-frame on the back end - quite an interesting idea, though. However, loosing the A-frame could have advantages like saving weight (probably negatated by the time cross links are added) and freeing up more potential storage space.

[Daan]

Bill, no DII axles at the moment and I am staying A-frame on the back end - quite an interesting idea, though. However, loosing the A-frame could have advantages like saving weight (probably negatated by the time cross links are added) and freeing up more potential storage space.

Wonder were you got that idea?

[will_warne]

Wonder were you got that idea?

[plasticbadger]

To chuck in my three pence worth, I'm nothing but impressed with my own 3 link front end (centre top link). I've done about 300 road miles, 3 play days and 1 weekend at Seven Sisters so far and found the following:

The cheap 3/4" rod ends are showing no signs of damage (yet) and I've put enough load on the front end to shear the end off a standard LR stearing ball joint and I've bent one of the lower arms, but no rod end breakage

It drives ok on the road (for a 7" lifted Discovery) - in fact my wife prefers driving it now than before 3 link!

It was cheap - it cost me about £150 and 3 weekends work to build!

The articulation is DRAMATICALLY better than the standard hockey stick setup, it flexes smoother and dislocates more than the rear.

[roguevogue]

[simonr]

No wonder those arms are Orange(ish) - you've copied that design from Will!

Si

[will_warne]

Step away from the spoon Si!!!

[Warthog]

Nice work undertaken. I was still thinking very similiar set-up. But had been "put off" with the comments in the thread. Such like the third link joint strength and the axle actual strength to take the forces applied.

Be good to see how it performs..........

[roguevogue]

Be good to see how it performs..........

It worked very well, I changed to 1 link when I fitted the Toyota axles. Someone else has just fitted this kit to his 90. The predecessor was bolt on and used an A frame ball joint on the third link, it is still going strong on a RR.

[bill van snorkle]

It worked very well, I changed to 1 link when I fitted the Toyota axles. Someone else has just fitted this kit to his 90. The predecessor was bolt on and used an A frame ball joint on the third link, it is still going strong on a RR.

Now we are getting somewhere. The fab work on your 3 link looked neat and well executed, but I didn't like the plow hanging down below the already too low standard trackrod. Now that you have a one link you are probably well qualified to comment on the pros and cons of each system.

Bill.

[landroversforever]

i take it theres a panard rod with the 1 link, to keep side-side in check?

[muddy]

Yes it does/has.

[roguevogue]

The fab work on your 3 link looked neat and well executed, but I didn't like the plow hanging down below the already too low standard trackrod.

True, it does hang down but no further than the bottom of the diff. The seperation of the mounting points seems to be the most common cause of failure, i,ve seen more than one conversion turn itself inside out.

My current setup seems to be working rather well, I would have used an X-joint if they were available at the time but I used an M30 thread instead.

[bill van snorkle]

True, it does hang down but no further than the bottom of the diff. The seperation of the mounting points seems to be the most common cause of failure, i,ve seen more than one conversion turn itself inside out.

My current setup seems to be working rather well, I would have used an X-joint if they were available at the time but I used an M30 thread instead.

Nick,looking at the side view of your 3 link I can visualise how such a design with even slightly less separation could turn itself inside out, particularly in reverse gear.It would depend on the total compliance of all the bushings, Most of the separation on some designs appears to be more horizontal than vertical.

Do you pivot your one link wishbone from a relocated (moved back) crossmember to replicate the antisquat/ antidive geometry of the old hockeysticks ?If not is the greater variation in pinion angle and castor as the suspension cycles a cause for any concern ?

Bill.

[dirtydiesel]

Nice work undertaken. I was still thinking very similiar set-up. But had been "put off" with the comments in the thread. Such like the third link joint strength and the axle actual strength to take the forces applied.

Be good to see how it performs..........

I'd be very concerned about the rover case bending.

I've bent a g wagon case using a similar setut to nick, and a freind of mine bent several rover cases before building something HFH would be proud of by heavily webbing a heavy wall box section out from the axle that enclosed the trackrod then mounting the lower link off that.

[Daan]

Nick, I see with both setups, you have built up some sort of tower that hit the bumpstop on compression, presumably to limit uptravel. Is there any specific reason for this?

daan

[landroversforever]

as far as i know, it saves having really long bumpstops which could get ripped off.

[roguevogue]

Nick, I see with both setups, you have built up some sort of tower that hit the bumpstop on compression, presumably to limit uptravel. Is there any specific reason for this?

This is to prevent body/tyre interaction nothing to do with the suspension directly.

DD, I haven't bent a Rover casing yet but then I don't really do off-roading to any great extent.

Bill, the mount is on the front of a tubular replacement cross member in the same position as the original, the pivot is in front of the output flange and as a result the prop gets close to the arms on full drop but the lack of clearance is down to me trying to keep the arms up out of the way.

[dirtydiesel]

DD, I haven't bent a Rover casing yet but then I don't really do off-roading to any great extent.

It's quite suprising how little it takes, i've an old vhs of the tuff trucks trophy from way back when, in that another friend of mine punched a bank at no more than 10 mph in his 3 linked g wagon hybrid. the impact was enough to push the tyre off the bead but looks totaly undramatic, the bend (more acurately twist) in the case was very impressive.

[Spectric]

Hi all

Just came across this article discussing three link systems on landys. It is something I have done some work on and in my opinion it is a good system to use if you want to improve the articulation of the front axle.

It must be stated that if modifying or fabricating any parts for your suspension then make sure you are using the correct materials and the welding is of a suitable quality, killing yourself is one thing but not some innocent bystander.

The std setup is ok & works, but it's failure is in the basic design. The two radius arms provide the dual function of fore & aft location as well as preventing axle rotation. Because of this the axle moves in a large radius around the pivot points of the radius arms & is why the castor angle changes as you increase the suspension height.

These radius arms also restrict the articulation because most of the twist occurs from their pivot points.

The three link system designed correctly will allow the axle to travel almost vertical & produce minimal changes in the castor angle, but you need the third link to prevent axle rotation, this is where any problems will arise. Not only does this link need to be strong enough to handle the braking loads but you need to get the geometry correct whilst working within the restrictions imposed by the engine sump above. The Safri Guard system was not bad considering it was designed as a bolt on kit, but if you fabricate your own plates and mounts then you can get a neater looking system.

You also will need to address the front damper mounts as these are not ideal.

During initial testing of anything you are doing something I have used in the past to find things that don't feel quiet right is a fit a small camera to allow you to watch a shaft or bush under load, ie heavy braking and sometimes this reveals something you really did not wish to see.

Roy

[uninformed]

thoughts from a carpenter:

something i dont see being addressed is the relation of the chassis mount and center of contact patch of the tyre. this only gets worse on lifted vehicles and when bigger tyres are fitted.

what do you all think of this?

looking at a stock coil rover front end, stock wheels and tyres, what effect would increasing the lenght of the radius arms by 50% and mounting the chassis end of the arm at the same height as the stock mount have on off road and on road characteristics?

Serg

[Escape]

thoughts from a carpenter:

something i dont see being addressed is the relation of the chassis mount and center of contact patch of the tyre. this only gets worse on lifted vehicles and when bigger tyres are fitted.

what do you all think of this?

looking at a stock coil rover front end, stock wheels and tyres, what effect would increasing the lenght of the radius arms by 50% and mounting the chassis end of the arm at the same height as the stock mount have on off road and on road characteristics?

Serg

Lenghtening the arms can only be beneficial, as the angles decrease and forces are transmitted more smoothly. There are a few companies out there offering this setup.

[uninformed]

anyone else? would like to here Bill and John's input.

what about anti-dive?

Serg

[bill van snorkle]

OK Serg, this is how I understand things as it would apply to a road registered Landrover that is used for regular medium to long distance touring in addition to occasional serious offroad usage.Unregistered Winch challenge or other short course vehicles can probably compromise more towards crosscountry than allround performance.

Longer front hockey sticks would of course permit greater articulation for the same size bushings. They also should give more precise directional stability over undulations and under brakes due to maintaining a more constant castor angle. Antisquat under brakes, or front end squat when climbing would be reduced a bitwith the longer arms but would still be positive compared to say a 4 link plus panhard. Generally,although there are exceptions, a 4 link with an appreciable degree of antisquat geometry will have compromised articulation capabilities due to bushing bind.

Standard length LandRover front and rear control arms are probably a compromise between on road handling and crosscountry performance. I heard or read somewhere a long tim ago that crosswind stability was also a consideration in determining the lengths and operating angles of these control arms. Apparently when the force of a crosswind pushes say against the right hand side of the body of a softly sprung RangeRover, the body roll that this produces,due to the control arm geometry pulls the r/h/s front and rear wheels slightly closer together whilst the l/h/s front and rear wheels are pushed slightly further apart causing the vehicle to steer into the wind instead of being pushed off the road or into the path of oncoming traffic in left hand drive countries.I'd imagine longer flatter front and rear control arms would reduce this crosswind stability slightly.

Bill.

[uninformed]

OK Serg, this is how I understand things as it would apply to a road registered Landrover that is used for regular medium to long distance touring in addition to occasional serious offroad usage.Unregistered Winch challenge or other short course vehicles can probably compromise more towards crosscountry than allround performance.

Longer front hockey sticks would of course permit greater articulation for the same size bushings. They also should give more precise directional stability over undulations and under brakes due to maintaining a more constant castor angle. Antisquat under brakes, or front end squat when climbing would be reduced a bitwith the longer arms but would still be positive compared to say a 4 link plus panhard. Generally,although there are exceptions, a 4 link with an appreciable degree of antisquat geometry will have compromised articulation capabilities due to bushing bind.

Standard length LandRover front and rear control arms are probably a compromise between on road handling and crosscountry performance. I heard or read somewhere a long tim ago that crosswind stability was also a consideration in determining the lengths and operating angles of these control arms. Apparently when the force of a crosswind pushes say against the right hand side of the body of a softly sprung RangeRover, the body roll that this produces,due to the control arm geometry pulls the r/h/s front and rear wheels slightly closer together whilst the l/h/s front and rear wheels are pushed slightly further apart causing the vehicle to steer into the wind instead of being pushed off the road or into the path of oncoming traffic in left hand drive countries.I'd imagine longer flatter front and rear control arms would reduce this crosswind stability slightly.

Bill.

thanks Bill, i'd love to see your libary, let alone understand half of it

with regards to the crosswind stability: wind hits side of vehicle, trys to push it, tyres have grip so body gets pushed, which results in compression on the left side as the right is raised. this compression of the suspension makes the arms travel up becoming more level, which pushes the axles away from there location.opposite is happening on the right, axle goes into down travel and gets closer(shortens the wheel base) so although the body has leaned to the left the car wants to steer to the right.

is this correct?

so as an example would you think that an arm 50% longer would be dangerous with regards to antisquat?

dont worry i wont hold you to it

Serg