you can run any pulley without a tune. its when you run hard ie: wide open throttle that the tune comes into play. to get the most out of a setup with cai pulleys exhaust etc. all req a tune. run a 178 without a tune and you say cool, run it with a proper tune and you say OH SH^^!!. run a 181 without a tune and you say, man thats gonna cost some money.
the concept of the c3 or 178 running without a tune is because the ecu can accomadate the inc. in boost for most of the runs. i have logged 19 psi with my c3. the ecu cant adjust to that much boost from oem without a tune

all of the pullies and cai's that are available for this car have been tried. pick whats best for your needs and then search for a tune. e/c , inmotion , oetuning, kleeman, renntech, buckhead imports all can tune your ecu. some have canned tunes some have dyno tunes and some have driving real time tunes. do all your homework, this isnt a cheap car to mod