Super old thread but are these springs still available and can you get them for a ute?

There was one guy on here who put a "Satchell Link" into his coupe (attaching bars from the axle housing to the chassis of the car like this /|\ (bottom of font is rear of car) - the two bars end up either side of the tailshaft tunnel - apparently their location can be optimised to prevent squat to help with I assume the location of the rear roll centre.

Maybe this could help when using JTS leaves, and possibly a rear sway bar.

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exactly - the inside front is lifted because the outside rear is too soft and too much weight has transferred there.

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on the 1200 you actually need the front control arms to be almost level to achieve a good roll axis inclination with a standard leaf spring rear end.

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well, excessive front roll stiffness is just another way of saying the rear is too soft... in my case the excess front 'stiffness' is caused by the front roll couple.

a well setup rwd car will lift the inside front a little anyway.

This is great stuff guys - keep it coming.

A couple of other things to keep in mind or consider:

One. Even though we talk about front and rear ends, it always has to be remebered that both ends of the car happen to be linked by a supposededly solid structure ie the chassis! Anything done to either end affects the opposite end.
Two. Further to the comments about roll centre heights, it is very easy to end up with a low front roll centre when lowering excessivley without some type of correction. Once the outer end of the control arms are level or higher than the inners, its time to do some research. This combined with the relatively high rear roll centre of a leaf-sprung rear end (with no additional lateral location devices) can result in a roll axis making a dive toweards the front of the car.
Three. Excessive front roll stiffness can cause the inside wheel lifting scenario (worse if the bar doesn't have enough droop travel as noted in a previous post). However, this is a compromise sometimes needed if competing with an open diff, to try and keep the inside rear on the ground & yet still try to limit the over-all roll to an acceptable limit.

Here is a comparison photo. Left hander at the top of the hill at Wakefield Park. JTS rear springs and a 16mm rear sway bar.
Note the Alpha behind has quite a bit of roll even on turn it.

adjusting the shocks won't do anything to fix this problem. Shocks affect transitional movements, but by the middle of a corner (like all the pics above) you are relying on the spring rate. besides that, the konis JTS does in their kit are only adjustable in rebound.

there are 2 main causes for the inside front coming off the ground. the simple one is excessively soft rear spring rate. which both white cars have IMO.

the inside front wheel coming off the ground is basically caused by excessive softness at the outside rear.both of those white coupes have alot more body roll than the red coupe to start with, and when you get on the power coming out of the corner (as in all these photos) you trasfer even more weight to the rear thanks to those soft springs. And when the rear goes down, the front comes up. The inside front was basicaly at full dynamic droop anyway (the amount of droop allowed by the swaybar) because of all the body roll, so when you get on the power and it squats at the rear and lifts the front the inside wheel comes off the ground. You also have less weight on the outside front thanks to the excessive squat.

the second cause for wheel lifting can be a declining roll axis. basically if the front roll centre is higher than the rear roll centre the car won't lean evenly front and rear. The roll centre is the point at which the body rotates around the suspension during body roll when cornering. if the front roll centre is higher than the rear, you get exactly what you see in the photo of my white coupe. the outside front doesn't compress as much as the rear because the body's pivot point (roll centre) is too high. anyone who runs those commercially available "roll centre adjusters" or "Bump steer correctors" has probably got the front roll centre far too high.

The red car doesn't have JTS leaf springs, it has a set I made from 1200 and 120Y leaves, and a 16mm rear swaybar. Its also much stiffer in the front, both in springs and swaybar (20mm 120Y bar). The roll axis is slightly inclined - the front RC is lower than the rear. The combined effect is it sits alot flatter and has lifted the inside front basically because its generating so much lateral grip. Its not beacuse of excessive roll or excessive squat, its just transferred all the load to the outside front because of the amount of mechanical grip it generates.

Cool - I understand more what you mean, the soft rear end causes the front to lift.

Creating some neg camber on the rear and dialing in the shocks will sort most of the problems....

Mine is also an out and out circuit car, cage, no sound deadener, floor coverings, etc....really a cheap copy of Andrew's (now Harry's) coupe. (His car was the inspiration for mine).

Sounds like with the JTS setup, a bit of camber and the right shocks that I can live without a panahard etc.... and that's what I'll do to begin with and we can see what happens from there.

I think I'll have about half the power of the 'ca18det_man' coupe to begin with.

Mildman as you can see the front wheel is lifting in all 3 cars. I agree with harry the car is soft, probably needed a couple of turns on the shocks to stiffen them up a bit. The front wheel lifting is not ideal and you can see how important it is keeping as much contact patch on the rear wheels as possible. Cause at this stage its really easy to oversteer...fun but very slow.
You need to run about 1 to 1.5 degrees on the rear end to counter this.
but if we are all talking about a street car, you will never bother about all this at all...the car will never be drivien to the limits like this...

Am I interpreting these photos right if I say the top shot (white coupe) front wheel has lifted but rear wheel hasn't - does this mean the rear of the car body is rolling but not the suspension?

Whereas in the second pic there is less roll in the front of the car....is this a reaction to a better setup rear end?

the JTS springs work weli, its just too soft. My old coupe always had resonably soft leaves (my own setup) to help get power down and a swaybar to control roll. I think a swaybar upgrade on my current Datto will make it really good. I have one for it and it would be on by now if i didn't think it was a bit too big.

JTS setup:



what I want it to handle like :