If you are using our curve for this media, the amount of WN 1 black ink is very narrow in the tonal scale and can not affect anything lighter than 95% gray. Examine the curve in QTR Curve View.
However, Carbon shade 2 is very warm and is mostly responsible for the 80 - 100% range.
And Shade 3 which is 75% carbon / 25% Selenium is responsible mostly for 60-80% range.
And Shade 4 is 50/50 carbon/selenium and carries some of this warmth to about 45%, though modulated by then.
Where are you seeing the warmth?
Is this the first time that you have used this paper? Is less warm on cooler paper such as EEF?
I would think however, that your prints have very warm 50-100%.
To cool off the inks - you need to replace the Carbon.
Shade 2 and 3 can be replaced with Warm Neutral to soften the warmth.
Shades 2, 3, 4 can be replaced with Selenium to make the prints cooler (like Selenium)
The ink set can be totally replaced to either Warm Neutral (less warm), Selenium (cold), or Neutral (quite cool in comparison).
Or shift to a cooler media like EEF and see if it is acceptable.
What do you think will work with your intentions?