Here's my take for what it's worth. Unless you are data logging or on a dyno of some kind, it's only a "canned" tune. Meaning info came from someone else's similar mods while being tuned on a dyno. If you want to do a tune, then you have to ask yourself where you are, and you really don't know without the above info. So, you can retune with a canned tune for a 178...but it is what it is... A canned tuned info may not even have been in the same geographical area as well. So, you get what you get. I got a great canned tune for my coupe but until I start data logging I won't know how great...and that should be soon since I am wiring it up now....good luck either way... I personally will never do crank pulleys. Just me...