What is it that limits how much the front of an 80 can flex

[BRE Fabrications LTD]

So just before Easter I checked out a few lanes in the Surrey area, write up to follow when I get round to it, and on one section of the one of the lanes I lifted the front DS wheel.

Not the first time I've done this but just wondering what it is about the 80's setup at the front that limits it's Flex ability?

The rear seems to flex out pretty well...

So is there anything that can be done to improve articulation up front without loosing road manners?

 

[Red Oktober]

Re: What is it that limits how much the front of an 80 can f

have you still got your anti roll bars ??

 

[BRE Fabrications LTD]

Re: What is it that limits how much the front of an 80 can f

have you still got your anti roll bars ??

I do.

I'd like to get a setup that would let the front flex out a bit more, but not at the expense on the road manners.

Does any one do sway bar disconnects for the 80?

 

[Red Oktober]

Re: What is it that limits how much the front of an 80 can f

softer front springs ????.... but i think anything you do to get more flex will compromise road manners

 

[Jon Wildsmith]

Re: What is it that limits how much the front of an 80 can f

Did your lift include ARB spacers? They help a little bit but best fix by far is ARB removal Also worth checking that your shocks have the extra travel or they might just be bottoming out.

 

[Paul_Humphreys]

Re: What is it that limits how much the front of an 80 can f

Paul

 

[Toby]

Re: What is it that limits how much the front of an 80 can f

Hi Ryan,

Once you've checked you've got sufficient shock and anti-roll bar travel, and your brake lines and breathers are long enough, you'll find the flex limited by the design of the leading arms. If the front axle twists much beyond that in Paul's photo, the rubber bushes that attach the arms to the axle run out of flex and start to bind. Some have experimented with removing one of the mounting bolts in front of the axle and got some extra travel at the expense of a lot of clonking and banging, and potential damage to the axle brackets. Obviously you'd be ill-advised (and illegal) to drive on a public road/row with it like that.

If you really want the front to flex as much as the rear you're looking at a 'three link' conversion - a lot of work. Especially if your truck has lockers, lifting a wheel here and there isn't really a major issue.

Have a look on IH8MUD - some of the Yanks really love flex...

All the best,
Toby
1990 HDJ80
1994 HDJ80

 

[Chris]

Re: What is it that limits how much the front of an 80 can f

Not being a Landrover expert, what is the fundamental difference in set up between one of those and an 80 that allows such incredible articulation? I see LRs with axles that move so much that they disconnect from the springs which are held captive at one end. Or is that due to the sot of modification that you mention Toby?

Chris

 

[Jon Wildsmith]

Re: What is it that limits how much the front of an 80 can f

IIRC LR's have a different attachment arrangement at the chassis end that means the control arm can twist without binding. The end of the control arm is a bit of bar with some thread on the end that goes into a bush with a big nut on the back of it.

 

[callum]

Re: What is it that limits how much the front of an 80 can f

At the front you don't get much more flex in a land rover, its a pretty similar radius arm arrangement. the bushes at the axle end of the radius arms are closer together, so the radius arm can twist in opposite directions around the axle a bit further before the limit of the flex of the bushes is hit, however the radius arms are further apart on a land rover, so that cancels it out somewhat. you can alleviate this binding somewhat by drilling the bushes or buying ones with pre made hole in them. Alternatively you can buy arms with a 3rd bush in them like these

http://www.superiorengineering.com.au/index.php?pag_id=24
explains a bit.

for the 80, you can also get one of these;

an x link by dobbin engineering. The front of your radius arms are bolted to this, which pivots about a central point of the axle. Can't find a link for the manufacturer i'm afraid. Maybe they don't make them anymore.

At the moment your flex is currently limited by the anti roll bar, as you've noted.

 

[Gav Peter]

Re: What is it that limits how much the front of an 80 can f

Now thats 'Fonda Flexibility eh???

 

[Brett]

Re: What is it that limits how much the front of an 80 can f

It's just the same for landrovers though, the rear radius arm bush doesn't really allow any extra travel, as with the cruisers all the flex is at the back (axle).

Unless as Toby correctly suggested you install a 3 link suspension at the front or an x-link as posted by callum you're not going to see a massive improvement by using longer springs, shocks etc.

The hinged radius arms & removing a bolt scenario aren't a very good idea imho although there are also recorded cases of problems with Land Rover 3-link systems where the axle folds back under the truck under braking!

 

[Chris]

Re: What is it that limits how much the front of an 80 can f

Just waiting for that to go 'Poiinng!' and flip over onto its roof!

Thanks for the explanation. I think I have seen that different attachment now I think about it. Makes sense.

Chris

 

[callum]

Re: What is it that limits how much the front of an 80 can f

here's a pirate thread to show development of some holey bushes. also lets you see a land rover radius arm. to compare with a toyota one.

http://www.pirate4x4.com/forum/showthread.php?t=61187

 

[Paul_Humphreys]

Re: What is it that limits how much the front of an 80 can f

My old 110.

Paul

 

[BRE Fabrications LTD]

Re: What is it that limits how much the front of an 80 can f

Hi Ryan,

Once you've checked you've got sufficient shock and anti-roll bar travel, and your brake lines and breathers are long enough, you'll find the flex limited by the design of the leading arms. If the front axle twists much beyond that in Paul's photo, the rubber bushes that attach the arms to the axle run out of flex and start to bind.

So would you say design wise it's binding of the radius arms in the set up that limits the flex?

I have seen these ( http://www.sleeoffroad.com/products/sus ... shings.htm) available, which seems to be what the drilling out of the bushings in the pirate4x4 thread evolved into.

I've had a look on MUD, alot on there regarding flex...

Has anyone ever seen a standard raduis arm with a rose joint on the frame side? Would this help alleviate some of the binding by possibly allowing the arm to rotate a bit more? Or are the standard bushes flexible enough allow for a fair bit of rotation?

As far as I am aware I don't have any spacers on my ARB. The lift comprised of just shocks and springs, well at least according to the receipt the PO gave me... Are spacers usually fitted with a 2" lift? I though it was only when you went above 2" that it became necessary

I'm not after crazy flex, just seems I'm not getting much at all in the first pic...

The 3 link set up will have to wait until I have a designated beater.

 

[Jon Wildsmith]

Re: What is it that limits how much the front of an 80 can f

Your lift needs 2" spacer blocks on the front ARB and longer drop brackets for the rear ARB. At a minimum adding those will make it articulate more easily and it will ride over smaller bumps better. Try jacking the front up till one wheel is off the ground at max droop (so jack the chassis not the axle ) and then disconnect the shocker on that side to see if it drops any more and a longer travel shocker would help or if it still has travel to spare.

 

[Toby]

Re: What is it that limits how much the front of an 80 can f

So would you say design wise it's binding of the radius arms in the set up that limits the flex?

Yes, once you've established that your shocks/ARB/brake lines(!) aren't limiting travel.

I'd imagine that drilling the bushes would make them more flexible, and allow more rotation of the arm around the axle, though by the time you've drilled enough to make a worthwhile difference you *might* find a negative impact on on-road handling, with the axle being less firmly located, especially under heavy braking or elk test conditions. Presumably the bushes wouldn't last that long either. Slee's products are usually well-resolved so could be a better option.

I don't think a rose joint at the chassis end would make much difference as a first step - though it might help once the limits of the arms rotating around the axle have been improved.

There are two 'directions' in which the front arms can bind - the first being the relative rotation of the arms to the axle casing when one side is on full droop and the other on full compression. The second is the twist of the axle relative to the chassis, though I think this usually only presents real problems with caster correction bushes which necessarily have less travel in this respect.

I'd forgotten about the X-link - certainly gives impressive flex, though doubtless at a price.

TBH unless your wanting to win twist-off competitions I don't think it'd be worth going beyond what the stock bushings will allow - lifting a wheel here and there isn't that much of problem and you can almost always get through anyway with a little momentum or use of axle lockers.

Flex tends to be a big subject in the Landrover world as they don't come with lockers and tend to break stuff if they use too much momentum (allegedly ).

The Superior Engineering kit looks like it would improve flex - ISTR they were working on an 80 kit, though again it might give interesting handling under heavy braking on the road.

As Jon suggests, find out what is actually limiting your travel and tackle that first; judging by the photos I'm not sure you're at the limit of the bushes yet. I'd also concur with spacing the ARBs - whether they're limiting travel or not they will work better in the correct position relative to the axles.

Let us know how you get on,
Toby
1990 HDJ80
1994 HDJ80

 

[BRE Fabrications LTD]

Re: What is it that limits how much the front of an 80 can f

Well I'm not out to win any flex comps but you lot have definitely given me some homework to do. Will do some investigating as suggested and let you know how I get on

 

[mike54]

Re: What is it that limits how much the front of an 80 can f

Not being a Landrover expert, what is the fundamental difference in set up between one of those and an 80 that allows such incredible articulation? I see LRs with axles that move so much that they disconnect from the springs which are held captive at one end. Or is that due to the sot of modification that you mention Toby?

Chris

On landrovers its the springs which lose the contact from the top mount but only when the vehicle has extended travel shocks. However, it needs to have disclocation cones in the top mount to prevent the spring from just popping out (ie dislocating). Also the A bar on the back axle arrangement will drop to quite a low level and whilst that doesnt directly help the articulation, it does assist. Also the Radius arms are far closer together on a landrover than they are on an 80 so this gives more articulation than an 80 if you think about where the pivot is and how it's doing it.

On the landrover forums people will often go on about removing the anti-roll bars to improve the articulation, but to be honest, (from a landrover point of view anyway), unless you're doing challenge events etc there is really no need. a landrovers articulation with standard length shocks and springs is more than sufficient for UK green lanes etc.

On an 80, in my opinion you dont need anymore articulation since you have front and rear lockers, unlike a landrover.