1.72 divided by 1.65 = 1.042. This multiplied by the existing cam lift gives the new lift. So: 1.042 X .625 = .6515. Whether this will work with your springs depends upon how good the person that set up your heads is. Most often we see spring problems: coil bind, retainer to stem seal clearance problems and such because the installer (usually someone in his garage,) just installed the new springs without checking/ measuring anything, and assumed that just because the springs were advertised for a certain lift that they would always work to that lift. Not so. Usually with any lift over .600 the valve guide needs to be shortened to allow for the desired lift and still have retainer to stem seal clearance. If the heads have had a valve job or two or a high lift cam is installed, the valve train geometry needs to be checked or corrected.
All of the above not withstanding, a gain of .027" is not going to be felt in "the seat of your pants," nor is it likely to be seen on a dyno. The other issue is that most heads, unless they are ported very well, will not flow hardly any more air or make any additional noticeable HP with only that amount of extra lift. IMHO the money would be better spent with porting, or more porting, or other upgrades to the throttle body or exhaust. TIMINATOR