i'm sure its just a wives tale (mith) from back in the day about them being a special head, there were "tons" of that floating around back then :-#, If you research, you'll see they were nothing more the a "police interceptor package", maybe a special cam shaft like an RV, 360 heads, exhaust (duals) & the QJ, special suspention for handling & higher rated tires for top speed & rain, The cop cars of the 80s were Diplomats, they were 318s, they handled very well & kicked butt, the cops loved them.