You can just make it out but it's not actually attached to the LCA's yet. It actually gives me more clearance than the old swaybar( which I must add was horrible). I can now get my jack under the crossmember from the front!

I've got some 225lb springs and some 250's. It does seem like overkill but the old datsun suspension manual reckons they should be even thicker! - I also happened to have this swaybar sitting around in the garage so the experiment sort of turned into the final product.

The manual wasn't referring to hollow tubing by chance was it? 25mm does seem mighty thick.
I run a 22mm bar and that may be a bit to stiff.

I think the cars in the old competition suspension manual may have been restricted to using standard or optional coils. your coils will be at least double what they were running.

although there is a bit of a trend towards a soft spring, big sway bar setup returning in touring cars, but you need specialised shock valving to really do it properly.

They definitely specify a 1 inch solid bar of stressproof steel. I have a feeling they were using Z car rear springs which are probably around the 150lb mark.

Mine isn't a very efficient design shape so won't be as rigid in torsion than the standard bar shape.

People forget that the shape influences its performance, not just the bar thickness.

the comp manual says they used 110lb/in front springs.

i use a 25mm front bar on the front of my 1600. although non adjustable it seems about right for my setup. i also run a rear bar which many people say is unnecessary but i have found it to help.

the car did seem to have plenty of body roll issues in your pics so playing with stiffer swaybars would seem a logical step. i have found a lot of improvement in the cars corner speed as well as powering out of corners can be found in fine tuning swaybars. good luck