From Wiki
It looks like 2004 the police interceptor got a boost but prior to that I see no evidence of the engine being differnt than the civilian model. I personaly think the 3 valve would be a better engine for the application(gobs more power)
http://en.wikipedia.org/wiki/Ford_Modular_engine
[edit] 2-valve
Vehicles equipped with the 16-valve SOHC 4.6 include the following:
1991–1993 Lincoln Town Car, 190 hp (142 kW) and 260 lb·ft (353 N·m)
1992–1997 Ford Crown Victoria/Mercury Grand Marquis, 210 hp (157 kW) and 270 lb·ft (366 N·m) with dual exhaust option
1998–2000 Ford Crown Victoria/Mercury Grand Marquis, 215 hp (160 kW) and 270 lb·ft (366 N·m) with dual exhaust option
2001–2002 Ford Crown Victoria/Mercury Grand Marquis, 235 hp (175 kW) and 275 lb·ft (373 N·m) with dual exhaust option
2003–2004 Ford Crown Victoria/Mercury Grand Marquis, 239 hp (178 kW) and 282 lb·ft (382 N·m) with dual exhaust option
2004–present Ford Crown Victoria Police Interceptor, 250 hp (186 kW) and 297 lb·ft (403 N·m)
1994–1997 Lincoln Town Car, 210 hp (157 kW)
1994–1995 Ford Thunderbird, 205 hp (153 kW) and 265 lb·ft (359 N·m)
1996–1997 Ford Thunderbird, 205 hp (153 kW) and 280 lb·ft (380 N·m)
1994–1995 Mercury Cougar, 205 hp (153 kW) and 265 lb·ft (359 N·m)
1996–1997 Mercury Cougar, 205 hp (153 kW) and 280 lb·ft (380 N·m)
1998–2000 Lincoln Town Car, 205 hp (153 kW)
2001–2002 Lincoln Town Car, 235 hp (175 kW)
2003–2004 Lincoln Town Car, 239 hp (178 kW)
2002–2005 Ford Explorer, 239 hp (178 kW) and 282 lb·ft (382 N·m)
1996–1997 Ford Mustang, 215 hp (160 kW) and 285 lb·ft (386 N·m)
1998 Ford Mustang, 225 hp (168 kW) and 290 lb·ft (393 N·m)
1999–2004 Ford Mustang, 260 hp (194 kW) and 302 lb·ft (409 N·m)
2003–2005 Rover 75, 260 hp (194 kW) and 302 lb·ft (409 N·m)
1997–present Ford F-Series, 258 hp (192 kW) and 294 lb·ft (399 N·m) ratings for 2007 and later model year F-Series
1997–present Ford E-Series, 225 hp (168 kW) and 286 lb·ft (388 N·m) ratings for 2001 and later model year E-Series