Good basic info Jmac. I went 120y away bar up front with 200b cut rear springs initially and then some trimmed HD kings for stiffer low ride. Was better when went 190lb coil overs but found needed stiffer springs on track. Picked up new unused 250lb springs but I think too stiff. 225lb would be better imho.

for my style and lowered rear I found a rear away bar also smoothed out the ride. Balanced the car from under steer to neutral. (that's as the Lpg.conversion then L conversion threw out my previous balance

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ADDCO out of the USA makes a 22mm sway bar for 1200. See Anti-sway bar it has prices and contact info.

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ah good, so nothing to do with any 1200 models that came to Australia. The standard 1200 bars here are 17mm.

Your B210 bars are different too. All our B210s are A12. I've never paid any attention to what year models I've got them off, but I've bought a few B210 sway bars for my 1200s, and owned a B210 wagon, three B210 coupes and they've all been 20mm swaybars.

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your experience with the Kings Springs sounds like it was from many years ago. The current lowered spring is pretty good. Variable rate for a comfortable ride and had noticeably less body roll than standard on the 120Y I fitted them too (same Part No for 1200 & 120Y KDFL-57). Also captive on the 120Y strut. And lowered the car the 30mm they said it would.They're a great spring for what they are designed for - a legally lowered street car.

120Y 20mm sway bar is all you need for a 1200 track car with appropriate spring rates. Mine had an L series in the front, cut Gemini coils (We estimated them at around 280-300lb) and 120Y sway bar. It was a great setup. Handling was its strength, not straight-line speed. It won its class pretty much eveywhere it went - Mt Cotton Hillclimb, Qld Raceway, Morgan Park, Norwell, and even at Bathurst's Mountain Straight hillclimb and Conrod Supersprint where I'd never been before. If I were ever to build another 1200 track car (which I wouldn't because they're just not cost effective compared to 90's turbo imports) I'd be using that exact same setup again in the front.

but that's a long way off topic. For a street driven 1200, a 20mm 120Y sway bar makes a huge difference to the handling!

Hi Harry,
Thats interesting what you are saying re your set up.
Whats your thoughts on how much stiffer you needed to go in the front to compensate for the extra weight of the L series verses the A?
I'm running 175lb springs with a standard front bsr ( tweaked to allow for the extra caster/ camber )and I think the car is great, still moves around a bit but the turn in is exceptional and the exit can be fine tuned on the rear bar, and that seems a long way off 280-300lbs.
Cheers
Dave

It was somewhere around 2009/2010 at the latest,probably not earlier than 2009 I can't recall precisely. I can probably make a better call on that if I log on to ozgemini where I got the springs from, as I chased that up not long afterwards.

If anyone cares I got em from a place in melbourne near the moonee ponds/ascot vale tram depot on mt alexander road. they used to be fantastic in the late 80s/early 90s. I've had other bad experiences there more recently (and that time with a friend's early 70s ford, of which surely there's been enough development that they'd have it all worked out, but the first set raised the car 2 inches, then the next set lowered it to near the ground. I'm wondering if they are sitting on old stock or something?

Maybe the ones I got were old stock/earlier design? Hell maybe they changed them after I contacted the qld head office about it (unlikely but who knows).

I`ll back up what Harry has said. I also use the B210/120Y front bar on my circuit car and thats with an A series. I couldnt imagine running anything much heavier than that on the road.
Spring rates are usially set as a function of corner weight for the road and tire grip on the track. For example, i have gone up 100lb in spring rate as our new control tire has more lateral grip than the last(both Yokohama`s), even tho the cars weight is the same.
That being said, spring rate can be exchanged for bar rate to a point.

Dave, 175lb is a pretty soft front spring for motorsport, but its all about the overall balance and there's more than one way to skin a cat. A higher roll centre will use a softer spring better too. Mine was pretty low.
I think the rear of my Datsun was about 180lb/in. It weighed in at 850kg with cage and 1/2 tank of fuel with about 450kg over the front axle. I've never tracked an A series 1200, but I would probably start at around 250lb in the front.
The 280-300lb figure for the cut-down Gemini coils was an estimate from the suspension specialist who does my wheel alignments. They had a few very quick Gemini series cars running out of their workshop so they should have a fair idea.

Thanks Harry,
I'll get them checked for rate next time they are out just to make sure they are what I think they are in rate.
Interestingly enough just got back from a NZ Datsun play evening at Ruapuna Raceway having run the car without a lsd ( I blew 2/3rds of the teeth off the pinion 2 weeks ago at the last Classic Car Meet fortnight ago ) and haven't organised a new rear end setup yet- what a difference! The car lacked the precision of turn in that it had before, felt unsettled through the turns and of course did the old 'spin up the inside rear' on the exit. I disconnected the rear bar and hated it so promptly hooked it back up!
I am staggered that an lsd could make such a difference on the turn in and mid corner handeling.
I guess one never stops learning...
Cheers
dave

I'm running 7/8ths front 5/8ths rear Addco bars which I believe equates 22mm front 16 rear and I'm using 250lb springs front and the nisom srpings rear which I think are 110lb?? The 250lb spring is as stiff as I want to go on treaded race tires,

Dave, I suspect that with the diff now open the car was likely over rotating and once it started lack of rear grip at some level would have to effect the cars ability to squat to a small or moderate degree. We know that a fully locked rear end requires a different set-up generally the car biased toward understeer on turn in. So not to belabor the point but if you've set the car up to perform with a LSD that performs like 30% or 50% fully locked dif and you go to 0% I'd expect it to turn like a fork lift if the set-up is unchanged......throw in the lack of forward bite and using the throttle to settle the car mid corner likely is less effective. If you think of the throttle adjusting the ride height fore and aft, the inability raise the front (dial in slight understeer) as well as rear squat for forward bite it makes sense to me that the car feels wayward.......................naturally a race engineer may tell me I'm way off the mark.............but given your feedback I'm sticking to my theory.

Tom my .02