Being on the Corvette forums for years, Corvettes are noted by all for having great gas mileage. The LS1 is a larger displacement engine with HUGE low end torque. I would cruise at 70-75 mph and be turning 1100 -1200 rpms with the 3.43 gearset and 6 speed manual trans.
The Coyote/Roadrunner just doesn't work that way, they have to spin to make power, that uses gas. And as stated the C-5 Corvette was a very slick car aerodynamically. Great "economy" car but the build quality of those premium GM cars will get you sick, Cavalier quality, with a Cadillac price. My Mustang is 5 times better built than the Corvette, and it is relatively speaking a less expensive car.
I'm in total agreement about the mileage although I am shocked to read that Corvettes are not that well built. I wouldn't know, I haven't been in one since my older brother had a new 1984 Corvette when I was 15. I figured with them being practically hand built in Bowling Green that they would have been of higher quality than a garden variety GM offering-guess I figured wrong.
I guess it has always been that way with GM vs Ford engines when it comes to brute, low end torque, and never more so since Ford went the OHC route with the modular V8's back in the early 90's.
I remember that my dads 86 Caprice Classic (305 4bbl Rochester carb) seemed like it snapped my neck more out of the hole than my buddy's 89 LX 5.0, even though he had both a huge weight advantage and 60 more horsepower. I'm sure the stopwatch would have told a much different tale than my butt dyno, but the feeling was there.
I do know that my other buddy's 87 Trans-AM (305 also) did beat my friends 5.0 to the top of first gear and a good bit through 2nd before the Mustang came roaring back past at about the point the TA was hitting 3rd (several runs at the strip, good fun back in the day, I need to get back to doing that).
What I love about our current Coyotes is that what we give up at the low end of the power band we get back in spades at the middle to top of the rpm range, and I am sure its even more of a hoot in your Boss :worship
Yet, even for all of that, we still get decent gas mileage if we drive them like normal human beings, even though we are pushing bricks through the air (relatively speaking when compared to a more areodynamic Corvette).