Interesting design, I hate to pick holes in it but you never know, it might be constructive. Firstly that bolt is undersized to be taking a lateral load like that. Threaded bar/bolts are designed for stress in pure tension. Sure you can use them like that but threads are horrible stress concentrators and that bolt will fatigue in time and may not show signs of it until it fractures.

Have you got any specs for those rose joints? That looks like one of the ~$20 items you get from the bolt shop and for the price I would like to know their rating because, and this is the most critical part, if ANYTHING lets go in this setup you may die! In any other standard/aftermarket setup they only rely on a spherical bearing/rubber bush to resist the shock loading and the corner weight of the car is always resting on the strut tower. If your bolt breaks or bearing craps out then the corner of the car will collapse and seize the front wheel.

I think the idea has legs but reckon you need to find a way to fail safe the design if you are going to be hitting ripple strips on the race track.

I got a huge shock when I saw the first pic of the setup. It looks so, empty.
The idea is very good but I am also worried about strength.
You must remember, in a gymkhana or any race condition, you will be loading up the outside strut considerably when going through a corner. I would almost say it would have double the stresses if compared to a car driving in a straight line.
The bolt in my eye is the weak spot in the design. If you can strengthen it then it might work. Also the plate that has the slides in it to adjust camber, you can make it much thicker to strengthen it. Maybe 10mm?
After talking to Rezlo, he informed me that we can get S13 camber plates for R800 a set (I think) and with apparently little modification fit to a 1200. Maybe that is a safer route. I don't want to be a spectator when the thing collapses in a corner. Another thing, do they do safety inspections on the cars before an event? I am worried that they might fail it due to safety issues.

well as i said before instead of nuts to adjust castor use small spacers, this would allow you to use a solid shaft with a threaded end. you will find this much stronger and your strut towers will let go before a setup like this would. you have inspired me to design something similar

Once I get the whole conversion done and know exactly what castor I need, my plan is to make my own bolts up. Like aidanel said, solid shaft with tread.

Also looking into bigger better rose joints, for the testing and mocking up phase these will have to do.

I have done a similar conversion on our Escort Mk1 race car, so far so good, it holds up, going to perfect it with the ute and then make the changes to the escort as it will be gathering dust for the next 20 months.

really seems like alot of effort when you get get S13 ones for about $100 if you look hard enough

I think its a very good start, any new design has alot of R and D and for someone actually doing something like this in a country where go fast bits are hard to find, is great. I dont know how to simulate a race scenario but try testing it in a setup that you can stand and look what happens instead of hanging onto the steeringwheel and testing like that. But I love the idea!

I know a couple of people have already said it but it's worth repeating... Absolutely do not use a threaded bolt in shear like that! The entire weight of the front of the car is on them, not to mention the cornering loads which can more than triple the force applied to that bolt. Threads cut into a bolt are like perforations in bathroom tissue, it WILL eventually break. A good airframe bolt has a shank to span the required length with 'rolled' threads at the end for clamping. Rolled threads are better than cut threads as they don't damage the hardening of the bolt. I would definitely use an airframe or ARP bolt ( or at least a Grade8, or 10.9 metric)with a long shank and collars of varying lengths to adjust the Castor. Also, that bracket looks to me like it would flex all over the place during cornering. Maybe weld some ends on it between the two verticals like a box, or gussets on the outsides of them. Just my two cents, I applaud the lateral thinking though!