Practice spinning faster in a lower gear on climbs. Lower gears at the same speed work your lungs harder and your legs less. My guess is that you might best climb at over 80 cadence with the 160 cranks. That takes practice. One can economically do a heckuva lot of deep breathing to keep the legs operational. As long as you're aerobic, there's really no cost to breathing more. Try 95 on the flat. If you have a trainer or rollers, a fun thing is to spin 120 in a very low gear for a long period. Fixes your coordination right up.