This one was particularly challenging as that Viper V10 was quite obviously not originally intended for the rusty and upright engine bay it currently rests in. The perceptive among you would have noted the shape of the firewall, location of the wiper motor, the fresh air intake and the dual hinge links and maybe, just maybe, if you've got the skill you'd have put it together and guessed correctly, a 1956 Ford F-100 pickup — the sleepiest sleeper we've seen since the Oklahoma Farm Truck.

[The Real JDM, (ironically)]

Today's question comes to us courtesy of master commenter JayP71. And that's all he had to say. We know there are better answers out there, but we'll play it safe and go with an old favorite. A few years back, the neighbors across the street had their house on the market. I was upstairs when I heard a burble. I peaked out my window and parked in their driveway was a bright red E39 M5. My jaw dropped. Just a thing of monstrous beauty. Especially because painted Clinique red the über-sleeper really looked like just another luxury-first BMW. But if you knew what to look for – those tailpipes and fatty meats – the big red car was simply mesmerizing. I quickly ran down and talked the guy's ear off until he let me take it for a spin. And no, he didn't like the house. You? – Jonny Lieberman

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Related:
How Many Of The Pope's Driving Commandments Have You Broken?; What's The Most Fun You've Ever Had In A Car?; The Jalopnik Question of the Day [Internal]

J-Lop all star Bumblebee proposed this one, apparently after getting spanked by a hopped-up CJ-7. Bumblebee isn't alone, as we got spanked by a sleeper recently. Pulling up a red light we notice a Caddy CTS in the next lane. It had but one tailpipe, meaning the car was not the awesome CTS-V. The guy starts gasing the car like like crazy, indicating that he's ready to go. We reel off the numbers in our head. We can hit 60 mph in about 5.5 seconds in the WRX, assuming we get lucky with the clutch. He's looking at 7 seconds, easy. This one is a no-brainer. We rev back at him. Light goes green and... turns out (after we tracked him down at the next light) that he had dropped a turbocharged LS1 from a wrecked Callaway into his Caddy. He was claiming 4 seconds flat to 60 mph. We have no reason to doubt him. Our ultimate sleeper would consist of that engine in some sort of wagon. Preferably our old brown on brown 1985 Pontiac Parisienne Safari Station Wagon. And we realize that's just us. So how about it? Describe your ultimate Q-ship.– Jonny Lieberman

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Related:
Sleeper of the Day: Plymouth Reliant; The Jalopnik Question of the Day [Internal]