In that thread here -
http://www.m3post.com/forums/showpos...&postcount=163 - ESS mentions +90F on non-intercooled setup, although this is running 5PSI of boost.
So I would guess 60-70F is probably more like it for 4.0PSI non-intercooled - but ESS surely have done more testing/refinement so maybe they are seeing only +50F non-intercooled @ 4PSI