I'm glad I started reading this thread! Very very interesting, and far superior to what I did on my last project which was to use a relay to override and run the fans with pressure monitoring via a trinary switch.
Just to clarify (for me, anyway
) : the E67 in the LSA crate motor offering from GM (pn 19259293) can monitor the A/C line pressure and turn on the fans? Does it do that with PWM support (just running the fan enough to keep the high side pressure to certain number)? Or does it do that by running the fans full speed until the high side pressure drops below a threshold?
And all the while, it's keeping track of the coolant temp and running the fans appropriately for that too?
Sweet!