If this helps you any I have a 95 GT making about 275RWHP and its never been drag raced, 53k miles, and 3rd an 4th are starting to go on it. Not TERRIBLE, but after some more seat time and some more bolt ons it will be done for.
Now this isn't to say the previous owner maybe had poor driving skills and contributed to this condition, but I just thought I would toss it out there.