yeah my friend said something about a possible cam job...i don't know much about mustangs but I'm learning. There may be some other work that I don't know about but I don't know if I would call it "stock" persay.... it runs rich..a lot of smell coming from the exhaust and the engine knocks when I get in the higher RPMs...but that may be because I ran 87 octane in it a couple times on the way up north .... the guy who sold it to me told me to change the oil with synthetic..that he used the racing synthetic... i always used 20/50 in my DSM (which I still have)..so I don't know how the synthetic will be good for the mustang..just gonna take his word for it I guess.