So, I'm almost ready to begin uber-smithing my chosen low-level items to be the equivalent of their Dragon counterparts, or as near to this as I can manage. I don't want to go over, or be under, by too much, so I am wondering if there is a way I can determine just how strong of a Fortify Smithing potion to make and/or just how strong of a Fortify Smithing enchantment I need to have?

As an example, a Stormcloak cuirass has a base AR of, I believe, 21. A Dragonscale cuirass has a base AR of 41--20 points higher. I'd like the Stormcloak cuirass to ideally be at 41, but a point or two more or less isn't a big deal.

Now, since my light armor skill will affect the displayed base AR, and there is no leather smithing perk with which I can double the improvement on leather-type armor, is there a way I can determine what I need? I don't want super-uber-duper armor, nor to I want something that is too weak.

I'd also like to do the same with weapons, so I imagine an answer to the above will help me understand how to precision smith weapons to Dragon equivalency... but bear in mind that mathematically, I'm a bit of a dullard; I can understand things, but the teacher might have to pretend I'm a first-grader in order to get there.

Since I don't have much time to sit down and play as a general rule, I really don't have the freedom to experiment as much as I'd like...

I've struggled with predicting the outcome of tempering an item. Here's an old thread where some of us kind of figured it out: http://www.gamesas.com/topic/1469973-not-smithing-at-flawless-but-should-be/

Hopefully, a developer will respond to you with the correct formula, but if that doesn't happen, I'd suggest you take a systematic approach. Try increasing your smithing skill and seeing if that gets you the AC you want. I'd hold off on mixing in a potion or an enchanted item as these may add too many variables. Save, try an experiment and then revert if you overshoot or come up short. I think you'll have to be patient when you want such specific characteristics in your apparel.

Good luck.