When adjusting the ITB's using the 2 set screws is there a way to check if it is done right? Can you use the vacuum ports on the top of the manifold?Thanks

yea use vacuum gauge to make sure they are all at the same level, i'd try to set them at idle and try to make sure they are the same at 2k rpm

Is there a range of vacuum it should fall in? Thank you

i have no idea