How do we pull 100,000+ Tokens from RAG?

I have a knowledge base with millions of tokens of context in it. Pickaxe does a great job of presenting the best 20k or so tokens to the model. But I can’t for the life of me find a way to get the model to pull more than about 20k tokens from the knowledge base.

I know there used to be a hard cap of 20k tokens. Is this cap still lurking behind the scenes?

Is there a way to set a minimum number of tokens the RAG engine sends to the model?