Corvettes?

[bluetwo]

Originally Posted by jamesqf

This of course depends on your standards for pretty good fuel economy. To me, 30 mpg or so highway seems pretty darned bad.



But the Corvettes aren't all that aerodynamic, with Cd values over 0.3 (depending on model). The aerodynamic engineering (as opposed to styling) that does go into the design is probably aimed more at creating downforce at speed, rather than reducing drag. They do get some advantage from having a fairly small cross-section area, so CdA is probably lower than most cars. But they're also pretty heavy.

If you want something similar, I'd start with a CRX (I got over 40 mpg with mine even the way I drove it :-)) or del Sol, a Miata, MR2...

All very true, and I know all that, as do most here on this site I think. There are still people who think the Corvette is much like the common muscle car where it just drinks gas and has no aerodynamic benefit, so thankfully that's not the case. For a BIG V8 Vettes can get really good mileage, of course if you're comparing a CRX it's not really too good at all.

[jamesqf]

I've occasionally thought that a Corvette might make a decent candidate for an EV conversion. If a lot of the excess weight is in the engine & transmission rather than the basic body structure, then you wouldn't be adding so much extra in batteries.

[MadisonMPG]

Originally Posted by jamesqf

I've occasionally thought that a Corvette might make a decent candidate for an EV conversion. If a lot of the excess weight is in the engine & transmission rather than the basic body structure, then you wouldn't be adding so much extra in batteries.

The LS motors are one of the lightest V8's.

[evolutionmovement]

Yeah, there are heavier I4s than the LSx. The Miata also doesn't get very good mileage, I've heard of people with C5 Corvettes getting closer to 40 (supposedly) while the few people with 1st generation Miata (1.8s) I've known only got in the high 20's—the gearing sucks and the aero is worse than the Corvette. Weight doesn't matter as much once at speed. That said, I'm sure a Miata could get into the 30's if driven like an old lady, but that's not impressive whereas a 5.7 liter engine doing that is. On the other hand, there's probably not much more to gain from a Corvette without changing the drivetrain out, while a Miata with RX-7 gears and a drastically reduced CDa could get into the 70s by my calculations (though my design would then be a single seater).

[evolutionmovement]

Annoyingly double-posted...

[Big Dave]

You gotta be kidding me. A 6-speed 'Vette drivetrain is optimal as is. Simply swap in a diesel and bingo! Big MPG.

[MadisonMPG]

Originally Posted by Big Dave

You gotta be kidding me. A 6-speed 'Vette drivetrain is optimal as is. Simply swap in a diesel and bingo! Big MPG.

ARGHHHHH Diesel Dave has shown his soot covered face once again.

A better gear ratio for the 6 speed would get better mpg.

[Big Dave]

quote:
"Diesel Dave shows his soot-covered face again.

Dave says:

You're durn tootin'. The whole point of the site is fuel economy. Says so on the home page. Do you think I'm gonna ignore an engine that is 50% more efficient? Do you think I'm gonna ignore an engine that does not have to be made less efficient to modulate power? Do you think I'm gonna ignore an engine that can run a wide variety of fuels? No, no, and no.

As for the Corvette, a manual 'Vette gets a 3.42 gear. One with an automatic gets a 2.73 gear. Put the automatic R&P behind the T-56 and now your top gear is a combined 1.36:1. You toodle down the superslab 70 MPH @ 1000 RPM. BTW, what but a diesel can make that kind of torque at a paltry 1000RPM? A 4BT3.9 Cummins does so easily.

[jamesqf]

Originally Posted by MadisonMPG

The LS motors are one of the lightest V8's.

Maybe so, but then I suppose there must be a lightest sumo wrestler, too :-)

But seriously, if all that excess weight - 3100+ lbs - isn't in the drivetrain, where is it? Lotus can bring the (European version) Elise in at around half that weight...

[Big Dave]

European Lotuses do not have to pass US crash tests.