What are the differences between twist and non twist forged cranked, like what are the advantages and disadvantages of each one, I can't seem to find any info on them.

 

It's tough to explain without visual aids, but I'll try.
A twisted forging is forged flat. Meaning that the rod journals are at 180deg instead of 90deg like the typical SBC crank.
After the initial forging it's twisted at the main journals to offset the crank throws to 90deg the way it should be for a V8.
This causes the grain structure to be distorted at the main journals, weakening it slightly at those points.
A twisted crank is stronger than cast, but not as strong as non twisted.
The factory forgings are mostly twisted.
AFAIK, one of the most failure prone areas of a cast crank is at the snout, and that area is not twisted on a factory forged crank.
(I may be wrong about that last part)

 

Alright, Thanks.