Some of suppliers of crushing machines provide, in their catalogues, all characteristics including PSD of crushed product. According to this you can approximately foresee the PSD of product.

However, it depends on material hardness (low, middle, high). Also you have to know material feed top size and size reduction ratio. Based of this it is easy to calculate product top size. The next step includes type characteristics that depend on material hardness (i.e. for middle hard ore, the type characteristic is 1.9 for R=0). Based on this you can calculate the size of crusher discharge. Please note that, type characteristics are being selected according to in advance adopted oversize R as well. In addition, there is exact value of type characteristic that corresponds to each R value.

I do hope it helps a little bit. I think there is developed excel sheet for determining PSD of crushed material. I would like to know more about that.

Also, the crusher gap is at least related to the product size P80.

The following formula: CSS = 1.25*P80 - 5.625

There are some potential predictive tools and depending on the purpose and accuracy they require different information about the breakage behaviour of the ore.

When it comes to possibilities to adjust and tune PSDs from cone crushers there are also a selection of different possibilities. 

There is transfer functions that can describe the crusher feed to product, and can be related to gap and throw. I co-wrote a paper for the IRR 3rd Annual Crushing & Grinding Conference 2001, that shows an excerpt using excel spreadsheets to relate a typical crusher transfer function very similar to the BII method described by Austin. You can develop these from manufacturer crusher curves, at known CSS/OSS.