Not sure how long it will take, put I sure like how it sounds. I have the same cat back. You said you were getting the whole exhaust, that is good. My car was not real loud until I got my off road H-pipe installed. That really made it sound bad a$$.
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White 1995 Mustang GT
Dynomax Cat-Back, Offroad H-pipe, K&N Filters w/o Air Silencer
My 1995 Mustang GT