Digital BW, The Print

I recently installed a Niagara III CIS with MIS pigment inks.
I had a tough time getting it going with lots and lots of bad nozzle 
checks and cleanings...before I learned I just had to let the thing 
rest overnight to settle down.

I find that if I don't print for a few days the nozzle checks are 
really bad and I have to do two cleanings, then run a test print to 
get the thing going.

My question is...the images from my Canon A80 routinely show as 180ppi 
when shown full size in Photoshop.  I would like to print them at a 
higher resolution, but same number of inches.  Does it do any good to 
resample for higher resolution?

Isabel