Dave,

I run an Addco 22M (7/8ths) front bar and once I fitted coil over struts, thus lowering the car even more, I noticed the bar was starting to bend the flat where the lower piece and upper box section of the chassis rail are welded together. This was in the area just below the bumper bracket mounting bolts thereabouts. Initially I flipped the bar so the sides had a downward slope. After that the front suspension was revised again and I used a short linkage/rod end set up. Note my car uses ZX struts with modified (longer) ZX lower control arms.
The orginal set up used Z car springs which were on the soft side, I use 225 fronts now, the old set up was really well balanced and easier to drive but the car is faster with the stiffer springs although 225 is still on the soft end for a track car.

As for shredding the front tire, if you can do some testing I'd see if the problem is resolved after the sway bar fix. As mentioned a cheapy infra red tool will do well enough, if after the sway bar fix it's still heating up the tire dial some camber in it. On the site we have discussed camber many times and it seems to vary wildly based on tires and car. Where as Harry ran 4.5, do to using bias ply tires I run 1.5 negative and the tire temps across the tire are very close. I also run a slight bit of toe in. I bring this up because my set up is very different but works well for me, obviously yours is different and other than cooking one tire it works for you so I would be catious about making big changes, again see what fixing the known problem does. Now if you can squeeze in a track day type event to play with springs and such it could be interesting to if there are any gains to be had.

Tom

Hi Tom,
I noticed the bar was starting to bend the flat where the lower piece and upper box section of the chassis rail are welded together. This was in the area just below the bumper bracket mounting bolts thereabouts.
Thats exactly what has been happening.
Many thanks for all the input and I'm now starting to get a much clearer picture of what has been going on and what I need to do about it.
Cheers
Dave

crossplies and radials have very different geometry requirements.

This was my old coupe with the engine out, and swaybar chassis mounts disconnected to give me room to remove the engine. Swaybar rests on the chassis left to its own devices. It had a 10mm spacer under the chassis mounts because it was fouling that outer edge of the chassis back when it was a street car. With approx 300lb springs and 20mm bar it was fine with the spacer.

Harry- you are a champ! Great picture there and a heap of negative camber.
I have wondered about putting a bigger front bar on as well but I have always been told that the sway bar should be nothing more thana fine tuning device which is pretty much what I have done at the rear ( mk2 Escort Sport - adjustable)
No spherical bearings or rod ends or am I missing something?
So if you don't mind me asking what do you do to your rear springs as far as beefing them up to balance what you had done in the front?
Cheers
Dave

yeah, that was certainly the old school of thought on sway bars. But alot of V8 Supercar teams and stuff have been running big swaybar setups with softer springs for several years now. My current 120Y has a 22mm Maddat front bar and it feels good in corners just with lowered King springs - certainly no excessive roll, but I haven't had it on a track yet... soon hopefully!

The old coupe pictured didn't have any rod ends as you noticed - Improved Production rules don't allow them. It was Stanza LCA & struts. redrilled LCA pivot to get some more camber and slotted strut tops as per the 1200 competition suspension manual. Gave about 4.5deg camber. Extra thread (rolled) on the 1200 castor arms - you can see how much is poking out the front to get the 6 or so degrees castor.

Rear springs were 1200 main leaf, 120Y 2nd leaf under that. On top of the 1200 main leaf I used a cut 120Y main leaf as a reverse half leaf. Then on top of that I used one of the other 1200 leaves upside down - I think it was the 3rd leaf out of the 1200 pack, but I'm not 100% sure now...
I also had a 17mm rear sway bar - pretty big, but it helped eliminate the understeer caused by the locked diff, and it turned in really well. Rough measurement of the combined rate of leaf spring and bar was about 180lb/in I think.

Dave / Harry for sure the bias ply tires are from a different world

For comparison front bar 22mm front 22mm rear with 225 front springs. As for the rears I think they are 119 , they are the comp springs per the suspension manual which are supposed to be 10% stiffer than stock. I am one who is in the soft springs stiffer bars camp, for me it seems to be the best mix of suspension compliance and controlling weight transfer. I am willing to give up some of that instant feedback for the extra bit of grip the softer suspension brings, that and I tend to ride the kerbs so it helps with that as well. For me this is the same trade off adding the extra tubing for chassis rigidity despite the extra weight, I only bring this up because I think the rigid chassis also allows more compliant suspension to be effective. Addtionally I run the LSD pretty loose as I prefer the way it turns in, with the lower power levels I can get away with it.

My .02 Tom

Thanks Tom,
Thanks for your input- much appreciated.
I had a quick on the Addco website and those bars that you are using look interesting. Any idea where I could get one of those?(US company set up for export )
I'm slowly getting a really good idea of what I need to be doing however step 1 tomorrow is to get the front springs that I've been using rated so I know what I am dealing with, then get some bar spacers made up to sort the fouling issue out.
There is still a question mark on the rear as the right rear tyre also took somewhat of a pounding but I suspect that this may have been a byproduct of what was going on up the front.
Lots to consider but at the end of the day I'm pretty upbeat about it all as the car was really good with all these things wrong so its going to be interesting to see what its like once I get it all sorted out.
Cheers
Dave

Well, what a morning- time to get the cheque book out!
The springs are approx 220lb so not as bad as I thought but the strut inserts are completely rooted so the pieces of a rather unpleasant jigsaw are coming together.
Come to think of it those inserts must be 20 years old!
I'm pricing up some Bilsteins and Eibach springs to match- the question is now do I go 275 or 300? Plus I'll need top hats to go into my spherical top mounts.
Then there's the bigger sway bar and rca spacers...
Cheers
Dave

Dave I feel your pain I just got done going through my struts as well, I used the MR2 rear inserts for,my 280zx struts. As for Addco bars I looked on Friday and JEGS will ship international. As for the spring rate, my first thought is why change since the you run well with your current set up but springs are relatively cheap so I would be tempted to go up to 250 first. Also what contributing factor did the worn dampers have on tire wear, possible none but before you pony up for parts can you replace the struts inserts, then test the car and see what the tire wear is like?

Tom

Hi Tom,
Thanks for the info on JEGS and the wise counsel.The strut inserts definitely have to be replaced and the sway bar dropped so it doesn't foul the lower body work but what you are saying about the rest is quite correct.I'll see what the quotes come back like on the springs as I really would like to try firming things up in the front but as you say maybe 250 would be a good place to start but much of what I do and the speed that I do it will depend on how these goodies price up.
Then get some testing done...
Cheers
Dave