The Mercury Marauder (newer) it is a car (essentially a Crown Victoria with a little extra oomph) and brand that most people associate with the elderly, but it uses a power plant most often seen in performance packaged mustangs (the quad cam Mach1).
Think Transformers: "more than meets the eye"
If you're in Florida don't be in too much of hurry to race a Mercury Marauder. The highway patrol has some as unmarked cars. And they're not stock either.
http://www.fordforums.com/f102/florida-highway-patrol-taps-reinhart-automotive-high-performance-modifications-102186/
The FHP always liked to have something faster than the average police car. They still have at least one '93 Mustang 5.0 in my area. There used to be some unmarked Mustangs too, painted dark gray with black wheels and dark tint. Those were sleepers!
My best sleeper was a '69 Ford Fairlane Cobra. It had a 428 Cobra Jet motor with ram-air and a 4-speed. It looked innocent with black steel wheels and a vinyl top and quiet with the stock dual exhaust. The only clues were the small hoodscoop with 428 Cobra Jet emblems on them and the little chrome cobra emblems on the fenders, but back then people stuck those cobra emblems on their fords.
One weekend I was driving at the local cruising spot and two guys in a '67 GTO come up next to me like they want to race. We were just going around 10 MPH in first gear when when the guy yells to me "were'd you get the hood!", in reference to the 428 emblems. I just smiled and floored it and lit up the tires from a roll for a good distance down the street. Mr. GTO seemed to loose interest in a race after that.
In that car I only lost one race to a car that was an even better sleeper in a way. At the time the black "smokey and the bandit" style Firebird Trans-Ams were popular and their owners seemed to think they were pretty fast. I however, was off a different opinion. My favorite game was to stay even with them at first, then drop back a little, floor it, and pull away from them.
Then one time I came across a perfectly stock looking and sounding Trans-Am on a highway that wanted to run me, so I did. We started at 40 MPH and he beat me so bad it wasn't funny to 100+ MPH. At the time nitrous wasn't really being used yet, so it most likely had a custom made turbocharger system. It would have been hard to keep a normal, healthy big-block Pontiac or Chevy engine that quiet.
The car I had before that was a '70 Ford Torino GT with a 351 engine. That was until the transmission went, which gave me an excuse to buy a 429 Cobra Jet engine with a C6 trans that I knew a local junkyard had. Of course with my sense of humor, I had to leave the 351 emblems on the fenders!