My new outback's brakes are um - lacking. I understand the discs on the 01+ were bigger. Is it a simple retrofit or do calipers need to be somehow moved outward as well? Thank you!

you might want to describe lacking brakes, what is wrong exactly? is it all the time? there are many different brake set ups but most are easily interchangeable and dont' require anything but the complete caliper and bracket and rotors.

 

often a complete fluid flush (your fluid is 10+ years old now) and a quality brake job - regrease the caliper slide pins, resurface the rotors, and get something other than the cheapest pads available will vastly improve braking.

 

has your fluid ever been changed?

have all of your rotors been turned?

have all of your slides been removed, cleaned, greased, and boots replaced if needed?

 

if some of those items need attention, you might want to start there. if you do swap, a lot of your "improvements" will simply be because you're including the items above in the project, not because they're "bigger". the dual piston calipers and rear discs that your OBW should have should perform quite well when in perfect working order for daily driving duties.

 

if you still want to. when swapping to larger calipers you need to make sure your wheels will clear them. most of the cheaper and easily available larger brakes will fit under 16" wheels. if you're running any 15" wheels you may have issues, but should be fine since you probably have 16" and you already have dual piston front calipers so they obviously clear fine. some of the larger and more expensive set ups require 17" rims, but i doubt you'll be going for those anyway.

 

you'll want to read jamals brake caliper thread, i believe it's in the USRM.