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yep, sway bars to stiffen it up a bit or a well engineered watts link to alter/adjust the rear roll centre.

I'm going the sway bar route because it worked very well on my old coupe.

Harry is completely correct these springs are no where near a modern well set-up IRS car however over any other solution as far as a 1200 is concerned I know of no better spring. I do know some people Chris (aka Dattoman) on the club has converted the rear to a 4 link setup, however he has yet to prove it in race conditions.
Also if you go for this then the forward upper leaf spring mounting bushes need to remain stock as having nolathane in then ties the back up too much making the high speed twitch worse.
I think what myself and Harry means by mid corner twitch is that the car wants to swap ends especially when you are about to apply power this is not what you want to happen.
The rear camber did dial alot of that out and the yellow car around the same track with the same engine was considerably faster with the same rear setup...only thing different was the camber.
I dont think a sway or pahard will help much its the contact pad of the tyre which is compromised at this stage. You can see here in this photo the rear really fighting for grip in mid corner compared to the front. the sidewall is bending over itself and the contact pad is minimised.
[img]http://datsun1200.com/modules/myalbum/photo.php?lid=5882&full=1[/img]

This would be especially bad in Harrys car cause of the extra power he is carrying and speed into the corner..it would be un-nerving. However again its the best setup that i know for a 1200 at this stage...

Good to know Harry

I also have looked at little into a Satchell link - which can alter suspension geometry a bit - it's meant to be another alternative to a panhard/watts for lateral support.

I imagine a watts linkage might be easiest to adjust though.

EDIT: Here's your pic converted.



I will definitely by ordering some JTS springs - and good point about bushes converted will either get the bushes from JTS as well or chat further with you to make sure I get the right ones.

I'll be driving my CA coupe before and after JTS springs to see how much difference they make, then probably looking at getting some camber on the rear to see the difference there too.

It' great to get this info out to all of us Datto drivers, last thing we want is a car that doesn't handle corners!

there a guy in townsville name Wayne Satchell who has raced 1200's for many years and who recently bought my yellow coupe wonder if its the same person?
He told me he spent 10' of thousands developing the rear of his 1200ute and cant wait to see if my JTS coupe is better or worse...oh by the way my old coupe will be powered by an ex-works BTCC SR20 rated at 320bhp (alot more than my 180bhp SR20)

I think Satchell was an American guy - you can see what a Satchell link is halfway down this link.

http://www.carbibles.com/suspension_bible.html

Like this pic - just imagine leaf spring instead of coil spring.

Sure you didn't mean Shane Satchwell there Converted? He used to run the Killer White 1200 ute with self built independant rear suspension. Last I heard of the car before he sold it was that he wanted to convert to SR power

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 :

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?

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...

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.