Tacet-Conundrum

I was watching Chasing Classic Cars the other day where Wayne found himself at "EASY" in Emeryville, Crap I can't believe I lived in San Pablo for 16 months and didn't even know this place existed! Any how, Wayne and the Founder of the group was talking about how the FIA published a Booklet that mentioned how to go about Prepping an 911 to put more power in it and to handle better.

Does anyone know what he is talking about, not Wayne but the founder of the Gruppe R?

Thank you

Tim G