A new way to lower jumbuck rears

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whiteseries4

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Nov 26, 2013
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melbourne
Having just bought a jumbuck I'm now in the process of lowering it, fronts are easy as putting a set of lancer coilovers in there but lowering a "axle" I use that term loosely, is a bit more involved considering it runs an offset stub axle that sits BELOW the leafs
Now I'm not really looking to awd anytime in the future no "put a real diff in there" comments plz D:

A few ideas I've come up with are

Like I've heard a few ppl do just re mount the diff above the leafs, good but you will have to cut and re weld the mount pad and shock mount for it to work. And even then your banging on your cut down bump stop since there's no room between the tube and the frame for any travel

Get a different tube axle without the offset

something I just thought about as Im writing this, the whole hub/brake assembly is connected with 4 main bolts so I could make 2 plates(1 either side) to re offset the axle to sit higher, that way all mounting points stay constant and the only thing that changed is wheel hight
Now it may have to be braced as the stock offset is but I think it might work

My best idea before that one was to move the front leaf spring pivot point more towards the rear and as high as the recess will allow you to go(you will notice the further you move that point back the higher the chassis rail raises
You will notice the rear shackle pivot will get close to some rail near the rear of the car but I guess you could get a pretty good drop that way
The only things I see that need to be addressed I'd moving the axle back to center( I'm not sure if there is a locator pin on the leaf) and that the leafs themselves don't get distorted in a way that would make it to unsafe

Any feedback or maybe a different way completely any of you guys have?

I might get some sketches of how those 2ideas will look once I'm back at my pc
And some pics of my new 2tone champagne/white jummy
 
but i also had thought about "raising" the hubs like you have said. but went with the flip cos it was easier

ill try to find a pix later 2nite if you want
 
Redo the end plates as you have suggested. That way you arent cutting into the bump stops or messing around.
Cut off the plates and remake them as you want them.

Playing with the spring perches will upset braking in ways I dont understand. Its the same as squat and lift with acceleration but in reverse.
Dont mess with it unless you know about it.
 
or ill have lowering leafs up for grabs soon too.. haha. jack how are you doing the 4 link setup? ill have to pay you a visit. im thinking about ladder bars with a panard rod in the back now
 
yeah i think plates are the way to go for me, im terrible at welding. but fabricating a plate i can do
ive got a few of these heavy steel plates and the thickness of them might work since at the same time i would like to gain a wider rear track

the lowered leafs, seeing there in perth it wont realy be worth shipping them all the way to vic

i would love to see your cut axle thou

and some pics so far




 
a few pics from the parts car and some of the metal plates
picked up the lancer for 1500 from nsw
came with brand new BC coilovers, guinuine hks front mount and piping
full 3inch from the turbo
plus it looks like its been rebuilt some time in its life since im getting like 160's psi on comp tests and what looks like a metal headgasket
its just a mock gsr so just fwd but im hoping its got a decent gearbox with a lsd
 
So are you going to swap it all into the ute?

I had a good look at mine before and thought it would be best to do the end plates.

Still looking into the 4 link, but pretty much what we looked at last time you were here.
 
the only thing i see to be a problem is if i drop the axle too much the lower shock mounts will be very close to the road, maybe a combination of that AND raising the leaf mount

yeah its all getting swapped, engine gaurds bonnet and all the skirts but i think ill keep the standard dash even thou i much prefer the lancers

i think i have a chance at even using the rear coilovers since the lower mount and the overall lenght is right, its just the upper mount is the 2 bolt pad setup. if i can change that end to a screw in rose joint i might
end up with a extra set of springs to firm up the rear, worth a try since there something that will just sit on a shelf

ever considered slapper bars instead of all the work for a 4link? im sure you have but i get the feeling that you want to keep your jummys load rating and all the extra mount points might make you hesitate putting a real load in it
 
Pins on the leaves, and holes on the axles.

The proviso of the 4 link is-
Similar suspension travel to oem,
Maintain load capacity,
Keep fuel tank in std location,
Nothing in the tray.

Thats probably it. I was talking to a fab guy and he says he just builds them to andra specs, so that would be fine to load 500kg in. It only takes it to 1600kg and thats not that heavy.
The fab guys issues were that the top of the diff will hit the tray. I must look into that bit.

Will be good the jummy conversion. There is a few around.
You should look at joining the jumbuck yahoo group. Vk2yg runs it and his 4g93t jumbuck is niiiice. Good info on there too.
 
I think you will find the rear is firm enough. Mine needs a leaf of bricks in the back to mellow it out a bit.

I have a rear cut here upside down to mock up rear ends. Even slapper bars dont do much, tramp rods (with the front tied in) are better. But neither are suitable. I think.
I thought about moving the springs upwards too, and that might be ok with slapper/tramp bars. Buy a 4 link is more adjustable.
Still thinking.
 
I've done the conversion you are thinking of undergoing. My complete interior is from an evo. You will need to swap over all looms and make a patch loom or cut and solider. For the tail lights etc and for the fuel tank. You will need to add top mount for the dash. Unless you don't mind it no being completely bolted down.

If you keep the proton interior and use the 1.8 you can get away with just changing the engine loom and doing some minor rewiring

You need to move the lower radiator mount to suit the lancer radiators, unless you change the panel completely

The skirts won't fit. You need to extend them by about 10 cm.

I've got a thread of here but not too much detail. If you jump onto evocoupe.net I've got a much more indepth thread. The first 20 odd pages don't have pixs anymore but the amount of info on there will help
 
I'll try to get some pixs of the rear axle but my computer is currently outta action, til I can get it back online
 
i had a few ppl contact me via pm about the conversion asking questions too. i know ive tried to put abit of detail into that thread and the good and bad.
 
i think ive gone thru your entire thread twice since im been thinking since before i got this jumbuck, theres some very good info there

some more work ive done, just removed the front leaf mount bolt and dropped the rear back down

now with it in position with a few spacers to give the shackles a few more mm to move im about to redrill the holes higher into the chassis, then after ill need to slide the axles forward abot 30mm
so im hoping ill be able to get another hole in the axle mounts to make that work
with that in place it looks like im down to 80mm with just the load of the body on it (down from std 140mm)

after this ill make the drop plates, and good news is the shocks will still have plenty of travel with this setup even though it will be quite low





i think ill be limited to about 40-60mm drop on the plate thou since the lower shock point is going to be low


sheds getting full
 

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