The BISS is used to get the ISC in it's operating range. Think of the ISC as a master and the BISS a slave. Blindly adjusting the BISS isn't really in your best interest, especially if you have DSMLink.
The FIAV, as I understand it, is for initially starting a cold engine. It's a chamber of wax that's hard when cold and slowly melted by the coolant going to the throttle body. As the coolant heats up and melts the wax, less air is let past the throttle body and the idle is lower. Many people run ISC and no FIAV.
As for the 4 nipples on the throttle body, just cap all 4 individually. I honestly forget which do what, but some are boost only, vacuum/boost, etc. Over the years I've realized that capping them individually is best.
Thumb through these sites for setting your ignition timing and fixing your boost leaks:
vfaq.com
plymouthlaser.com
The FIAV, as I understand it, is for initially starting a cold engine. It's a chamber of wax that's hard when cold and slowly melted by the coolant going to the throttle body. As the coolant heats up and melts the wax, less air is let past the throttle body and the idle is lower. Many people run ISC and no FIAV.
As for the 4 nipples on the throttle body, just cap all 4 individually. I honestly forget which do what, but some are boost only, vacuum/boost, etc. Over the years I've realized that capping them individually is best.
Thumb through these sites for setting your ignition timing and fixing your boost leaks:
vfaq.com
plymouthlaser.com