You mean the water delta? It's depends on more factors. What water delta you're aiming for, what rpm you're willing to run your fans, what rad you're planning on using, how many watts of heat you're trying to dissipate.
According to MartinsLiquidLab's testing, a thick 3x120 rad like the UT60 can dissipate 210W of heat with 1400rpm fans and water deltaT of 10 degrees. There is not much info on 3x140 rads but you could search this for the rad you plan on using.
A 3x140 has 36% more rad surface area vs a 3x120. Provided we're talking about rads with the same thickness. You're looking at 285W-300W of heat dissipation give or take in the case of the UT60.
The water delta is pretty much the same thing, yeah.
The point I was making is that if you're already able to run the fans slowly and dissipate the heat you're generating effectively that 36% more surface area becomes academic.