depends. take to machine shop, they can determine what (if anything) is wrong or not.
im kind in the process of gettin some on my car...
oh, and the P heads are better, but you will have to buy headers for those heads, or have yours massaged a little.
they have raised header bolts.
oh, and the end of the heads, will have 3 or 4 bars on them...
4 bars, are gt40P heads, and 3 bars, are gt40 heads.. same as what come on the 93 94 95 cobras.