http://page9.auctions.yahoo.co.jp/jp/auction/k121409244

It seems to say this is a Stage 3 rear spring.

The English language shop manual calls this a "leaf spring".
Triumph owners call it a camber compensator.
I think I remember some kind of aftermarket shackle assembly for early VW Beetle suspension.

For those unfamiliar: On swing axle cars, the rear end can lift in cornering and allow the rear suspension to droop. It's called Jacking or Crabbing in different circles.

The spring puts some upward force on the rear suspension arms and prevents them from drooping when the tail gets light.

Belletts came with one of these leaf springs as original equipment to prevent this from happening.
Triumph went back and added one of these springs to their design.

I have seen larger versions of this leaf spring described as performance upgrades. This auction adds a little more detail, they were apparently sold in different grades to match the need of the user. I have also seen some descriptions of adding or removing spacers from the end links to change the action of the spring on the arms.

We have a big leaf spring company in town, and I had planned on looking into making one of these things in a larger size just to see what it would do. This one looks like it has four leafs. The originals that I have seen have a single leaf.

Does anyone know any spring rates for either the originals or the performance versions?

We use a second leaf out of a parts car stiffens them up.

we make our own from units out of other cars too.
race car has 2 and a half under it.

Doesn't every one have a works stage three 4 leaf under their car, used to be available x Japan $106.00 landed

Currently negotiating, researching getting several different versions made.

Cheers
Rob

Has anyone tried to find replacement rubber/nolethane bushes that fit?? or can be adapted.

the centre rubber bushes no off the shelf nolathane that i can find yet, still working on matching up the outer round rubbers in nolathane style bushes.

Mine runs with a single leaf 9mm thick. It was developed by Arthur and a suspension crowd in northen subs of Melbourne. I can't think of the names. (help Brett) But coils are also stock height and around 420lbs rating. And adjustable Konis.

Peter

Thanks Peter, we were going to try a 6mm and an 8mm leaf with just about zero arch.

Cheers
Rob

centreline suspension. glen reid (who owns/runs the company) was a well known bellett racer back in the day around melbourne. had a waaaaaaaaaaaaaay modified, and very fast GT. was/is a PR90. car went to arthur, thru another owner, then to a current BCCV member (not a user on here tho) who also has a PR91, tho the 90 is a major resto job now. has been chopped about, hit, bashed, half ass repaired a thousand times, etc. it will all be done one day tho!
actually, some of the front suspension parts in my race car started out as stuff from this GT. very modified arms, bucket mounts, a few other odds and sods.....
these days tho, with respect to centreline's and belletts.............. don't bother asking. they're just not interested. some of us have tried, but get the cold shoulder.
shame really, as they are a clever group of guys.

mine runs a 4 leaf spring but im not sure on what the rates are...all i know is that its super low!

They discuss this camber compensator in the "Victor Memorial Car Series Volume 4; Bellett 1600GTR" video (1998). It looks like the video was done with the Bellett Club of Tochigi. I have not heard of them before, but Tochigi is the Isuzu distributor whose website has the big Bellett GTR information section.

The video shows an orange GTR running gymkhana and the dialog mentions "Stage 3" numerous times, and a couple mentions of "Stage 2". Some comparison of the two going on in the dialog. There are some specific detail shots of the leaf spring assembly with different numbers black plastic spacers stacked in the end shackles. There is even video of the rear suspension arm while the car is in motion, showing the suspension travel and the front tire in the background counter steering both directions. The car running the gymkhana has the ability to throttle oversteer with the front inside tire almost totally in a fixed position, making one of those tight drift turns arount a pylon for a 270 or 360 degree turn. On hard braking turns, the inside rear tire will actually lift off the ground. It looks a lot like a VW Golf lifting the inside rear tire. It sounds like there is also some mention of the differential in connection with the Stage 3 leaf spring assembly.

It looks like the Stage 3 might be set up for gymkhana and autocross, and the Stage 2 might be better suited for a hot street or road race upgrade where a little less oversteer might be desired.