3 link / radius arm suspension

[Mytqik]

Just a passing thought.

Has anyone seen / installed a 3 link-radius arm suspension into the rear of a 4x4???

Just so we are 100% clear on what I what to do, I am talking about the setup found in the front of RR, LC80/100 & GQ/GU's. That is 2 lower links which attach onto the diff housing at 2 points (see attached picture) and a panhard rod.

What would be the advantages/disadvantages of doing this. Has anyone ever run a radius arm upside down, so it attaches to the top of the housing to increase ground clearance??

I am not after massive flex, just a nice smooth ride out of my old girl. I like the radius arm idea as I am planning on having a large water tank & 3rd fuel tank under my tray & will have no room for a trianglulated 4 link.

Which has the longest radius arms GQ / LC 80 / RR?? Are one of these any stronger than the other? Does one offer a benefit that the others don't.

If this would work OK, I might contemplate doing both the front & rear at the same time. I would also have polyairs in the rear to maintain my load carrying capabilities.

The 80 series appeals, as it is close/identical to the 79 series front end & would be alot easier to get engineered than a full custom setup. As it is a factory produced item it should be easier to engineer for the rear too.

Any thoughts?? Suggestions?? (don't tell me to buy a GQ cause I dont fit in the tight arse cabs)

[RB zook]

that setup is standard in a coil sierra

i fount being in the rear it was so much easier to bend an arm i bent atleast 4 or 5 of them



also i fount the bushes would flog out fairly quick thou thay would be from to much flex for the design

[GRIMACE]

Hey as discussed on MSN, there is a custom rover (was in a recent 4wd monthly mag) thats running rover type radius arms front and rear (also has a toyo diesel donk).

I beleive the arms maybe legthened and buy the photos it seems to be a good simply setup.

Not a huge amount of flex (though with the haultech holey bushes it would be sufficient)

The better option would be the 80series radius arms as it doesnt have the pin mount used in the rover/nissan setups and should allow for a bit more flex.
EDIT: actually after thinkin bout this the 80series chassis end would bind from twist (rover and nissan wont) so flex may not be any different

Wat eva you do its gonna be better that your leaf setup as it is currently


Anthony

[bru21]

bundera standard setup too

[RoldIT]

bundera standard setup too

... and pajero. Work "OK" but nothing to rave about.

[kroozer91]

that setup is standard in a coil sierra

i fount being in the rear it was so much easier to bend an arm i bent atleast 4 or 5 of them



also i fount the bushes would flog out fairly quick thou thay would be from to much flex for the design

is that why it crabs down the highway

the front radius arms from rear bush to very front bush are about 850 long

[RB zook]

that setup is standard in a coil sierra

i fount being in the rear it was so much easier to bend an arm i bent atleast 4 or 5 of them



also i fount the bushes would flog out fairly quick thou thay would be from to much flex for the design

is that why it crabs down the highway

the front radius arms from rear bush to very front bush are about 850 long

wat u talkin bout
its rear steer

[bru21]

i would opt for another setup if you can. my bundera was outflexed by everything. but if it is just a beach or firetrail rig its all good. i just think a 5link rear is as much work and is essentially perfect

[DaveS3]

Disco 2 with a Watts linkage instead of panhard rod

[GRIMACE]

the bundera was probably lackin flex due to the shock bein to short, i know my cuz original shocks in the bundy he baught were to short (had about 1" of droop ) and we replaced them with ones that were to long.
Its still didnt flex great but was an improvement, i think the amount of flex Mytqik is after will be acheivable with the setup he is contemplating.

And if he can get as much flex out of the radius arms as i have in the front (with holey bushes) it would be morth than enough.
He has abit more weight on the front end so it should be forced to work alittle more aswell.

Either way I have seen one custom radius arm front and rear setup b4 (on that Hybrid defender thing) and i thought it was pretty impresive, and would like to see another one.

The flipping of the arms to be on the top of the diffs is a great idea too

[Slunnie]

Disco 2 with a Watts linkage instead of panhard rod

TD5 with ACE, I'm not sure if anything has a higher OE RTI. Radius arms front and rear. The radius arms that Rover have put into the D2 also have round bushes at the chassis instead of the common pin type.

[ebo]

[quote="Mytqik"]Just a passing thought.

I am talking about the setup found in the front of RR,
What would be the advantages/disadvantages of doing this.



lots of comp safari racers in england run range rover front suspension out back(radius arms,panhard rod)it is alot more controlled at high speed than standard set up.

[carts]

Wat eva you do its gonna be better that your leaf setup as it is currently


Anthony

I beg to differ. It may be more comfortable but my cruiser leaf front end flexs better than any 3 link setup i've seen.

[GRIMACE]

Wat eva you do its gonna be better that your leaf setup as it is currently


Anthony

I beg to differ. It may be more comfortable but my cruiser leaf front end flexs better than any 3 link setup i've seen.

yes but wat have you done to it??? Its not all about the flex either
I have no doubt a leaf sprung setup can be far superior to the front radius arm system but it wont be as smooth ride it wont be as road friendly and I know wat Mytqik is trying to achieve.
And i did mention that its gonne be better than his current setup not a custom setup

[Mytqik]

Thanks guys all good info.

Which radius arm setup should I go for??

RR cause there are a million of the things around & they date back to the early 70's so they can be picked up cheap?? How strong are these units compared to the Jap ones??

78/79/80/100/bundy cause it is a toyota part & keeps the car all toyota. May make the engineer happy as it is essentially just retrofitting the 78/79 gear into a 75.

GQ/GU: How do these compare to the others in size/strength/price/etc??

[GRIMACE]

BTW my RR cranked fronts are approx 760mm from the chassis mount centre to the closest bush (rear of front diff).

Mine are susposedly slightly longer than standard radius arms so youll prob find the standard rover ones to be around the 745mm mark.

[Tiny]

a well set up triangulated 4 ling ie 2 arms and panhard using good military spec heim joints should bw easy to set up and work well, laminate some chromloy tube and the arms should be exremely strong and if its is not for massive flex mount the arms further from the centre for beter on road manners

[GRIMACE]

a well set up triangulated 4 ling ie 2 arms and panhard using good military spec heim joints should bw easy to set up and work well, laminate some chromloy tube and the arms should be exremely strong and if its is not for massive flex mount the arms further from the centre for beter on road manners

you have lost me triangulated 4link... 2 arms???

[Tiny]

a well set up triangulated 4 ling ie 2 arms and panhard using good military spec heim joints should bw easy to set up and work well, laminate some chromloy tube and the arms should be exremely strong and if its is not for massive flex mount the arms further from the centre for beter on road manners

you have lost me triangulated 4link... 2 arms???

didnt explain real well but talking about the inner arms

[GRIMACE]

a well set up triangulated 4 ling ie 2 arms and panhard using good military spec heim joints should bw easy to set up and work well, laminate some chromloy tube and the arms should be exremely strong and if its is not for massive flex mount the arms further from the centre for beter on road manners

you have lost me triangulated 4link... 2 arms???

didnt explain real well but talking about the inner arms

hmm thats an interesting peice of kit
but different to wat Mytqik is wantin to achieve.

[Tiny]

a well set up triangulated 4 ling ie 2 arms and panhard using good military spec heim joints should bw easy to set up and work well, laminate some chromloy tube and the arms should be exremely strong and if its is not for massive flex mount the arms further from the centre for beter on road manners

you have lost me triangulated 4link... 2 arms???

didnt explain real well but talking about the inner arms

hmm thats an interesting peice of kit
but different to wat Mytqik is wantin to achieve.

yes but an option not to be ruled out if it is set up right for the job

[GRIMACE]

He wants to keep it all off the shelf stock parts and def doesnt want any a frame or triangulated design (due to clearance/space issues)
So althought its a good option (and that kit looks pretty good too) its not an option available to him ATM.

[Mytqik]

For sh@ts & giggles, how much is that fancy kit you posted up worth Tiny??
Any more details on it or links to the manufacturer??

[Tiny]

For sh@ts & giggles, how much is that fancy kit you posted up worth Tiny??
Any more details on it or links to the manufacturer??

best to make one to suit, need heim joints, decent tube for arms and best to laminate as well and time and patience to sort out the geomatry, you should sort a decent set up for the under the 2g mark if you do the work your self, just tack where it needs to be and get an engineering shop to tig it up for you especially on the chromoly as if you dont get the colours right when welding you will weaken the welds to the point you may as well have used steel

[Slunnie]

Thanks guys all good info.

Which radius arm setup should I go for??

RR cause there are a million of the things around & they date back to the early 70's so they can be picked up cheap?? How strong are these units compared to the Jap ones??

78/79/80/100/bundy cause it is a toyota part & keeps the car all toyota. May make the engineer happy as it is essentially just retrofitting the 78/79 gear into a 75.

GQ/GU: How do these compare to the others in size/strength/price/etc??

Disco2 units. Big bushes and better chassis joints.

[carts]

Wat eva you do its gonna be better that your leaf setup as it is currently


Anthony

I beg to differ. It may be more comfortable but my cruiser leaf front end flexs better than any 3 link setup i've seen.

yes but wat have you done to it??? Its not all about the flex either
I have no doubt a leaf sprung setup can be far superior to the front radius arm system but it wont be as smooth ride it wont be as road friendly and I know wat Mytqik is trying to achieve.
And i did mention that its gonne be better than his current setup not a custom setup

Don't get me wrong Anthony, i am not saying my cruiser is "all that," cause it aint. The leaf setup in the front is more or less stock, except for aftermarket lifted springs and anti-inversion shakles. Leaf sprung cruisers are better known for their front flex from the leaf setup and not so good flex from the rear leaves. In the 80 series however, the tables are turned. You get relatively poor flex from the 3 link front in comparison to the good flex from the 5 link rear.

As for mytqik (i assume he has a 75 series????), converting to a 3 link in the rear probably wont change his flex all that much, because the rear leaves are rather stiff in stock form. If he changes his front to a 3 link, then in terms of flex, i would suggest he would be worse off, but better off in the comfort stakes. Either way, if he just wants to achieve a more comfortable ride, go with a simple 3 link setup. Then you will end up with a 75 series bundera.

[GRIMACE]

the 3 link front of my rover has more flex then a stock 75.
And yes i know wat you mean as 80series front dont work so well, the same as the nissan ones strugle to move more than 2 inches, but setup custom they can be improved enought to be benificial specialy in this case.

If i could find pics of that damn hybrid rover i could show you that althought the flex isnt eye opening its enough for an everyday work car that will get you places offroad and be easy to maintain and be strong and simple.

[JemmyBubbles]

This 3link radius arm design can only flex soo much. That bind up much earlier during cycling than others. But I agree with grimace they can be made to be usefull... but only so much. Get the Rear Flexing well..

My general opinion is if you are reinventing-the-wheel/fabbing why not build something that is superior in design and functionality. Put the 3 link in the front go the 4 link in the rear.

If you are paying someone to do it I honestly think price wise you could have a triangulated four link on your vehicle for around the same dollars as a radius arm 3 link. You will be more pleased on trails and also the miscellaneous flex/pissing contests we alwayz inadvertantly get into.

Rather than wishing you had a few more inches to go
8====> could be 8==============>

[J Top]

Labour wise a "3" link will be heaps cheaper.
To improve flex and retain onroad manners slot one of the front diff to arm mounting holes, slacken the bolt for more off road flex and lock the bolt for firmer road manners.
Flame suit on
J Top

[JemmyBubbles]

FLAMEd....

But still dodgy...

Just do it right... 4 link with chromoly shart...