hey guys, i did a search and noticed how great the gas mileage is on vettes. how is that so with a 5.7 and a 6.0L block? what does chevy do to make the gas mileage so good on the highway? my old 03 SSR couldnt get that good mileage LOL! i was averaging around 15.5mpg on highway and city.

i really want to get myself a vette. i love these things!

 

The folks that are getting the great mileage numbers (like me) are driving the car very gently when trying for those high numbers and will have a 6 speed transmission. Engine is going slowly, car's wind resistance is low, and your foot is out of it. On rare occasions, I can beat my mileage down to a pathetic 26 but you can't run it up to redline in each gear because you like the sound or whatever, unless you are cheerfully willing to pay the big bucks for the gas. (which I'm not because I'm cheap) I like the idea of having it there when needed but not needing to prove it to everybody.

 

Well for one thing aerodynamics, the C5 is lower, and has less wind resistance.

Then there's the trans. The autos have a 2.73. And the Mans have six speeds.

Then there's weight. Doesn't take very much power to get it moving.

 

It has to do with the weight of the car, the CD on the car,and the gearing and the way the car's fuel management system works. Life if good when you can have a car with this potential and still get 30+ mpg on the highway.

 

yeah all this time i was car hopping, i never realized the C5/C6's got great gas mileage like that. i totally forgot the aerodynamics of the car really helps with the gas. do the C5's have skip shift or is that a C6 thing right now?

 

I have a 6 speed vert with the skip shift eliminator. ($10 or so) On my 75 MPH, 777 mile trip to Bowling Green, I got 36 MPG. (top up) Around town with a 50/50 mix of open road, some strong starts, I've never seen less than 20 MPG.

 

Some guys get great mileage by upshifting at 1500RPM and always keeping their revs in the 1000-1500RPM range. I can do that too but I don't like to see the junkmobiles behind me waiting for the first opportunity to pass. My engine wakes up at 3K RPM. So, I like to rev it at least that high in every gear but 6th. When I upshift at 3K most of the time and also hit the redline a couple of times a day, my true gas mileage is in the 15-16 MPG range (mostly short suburban trips).

BTW, most of the the guys who say they get 30MPG are looking at the fuel economy average displayed in the DIC. the DIC is programmed to lie. It tells you your MPG is 5-10% higher than what you would calculate on your own if you accurately measured what you put in the tank. I've seen that in every DIC-equipped GM car I've driven. There's even a fuel economy display adjustment parameter in the PCM. It can be adjusted with EFIlive or other tuning software. I had to ask the tuner to set mine to 0.91 to display accurate MPG. It was systematically overestimating MPG by 10% prior to doing that.

 

 

I average around 17 city but i never change gears at 1500 rpm - whats the point of having a sports car if you gonna drive it like an old lady go buy a Saturn or a Honda Civic

 

So that means I'm only getting 18 mpg?

Oh well. Still beats the suburban!

 

Both of mine (see signature) have gotten 30+ mpg when cruising I-75/US-127 at 70 or 75 mph with the cruise on. Oddly, it seems I've done better at that speed than when setting the cruise at 55 or 60 mph.

As was mentioned, I have never gotten below 21 mpg for a whole tank. That lowest mpg range only comes when some vehicular spankings need to be issued.

If you ever get a performance exhaust, expect to get on the throttle more than necessary as the sound is SO sweet!

Is there any other car with the Corvette's combination of history, looks, mpg, power, sex appeal, low cost:performance ratio, mystique, etc.? If you can find one, show me!

 

I have never driven mine in cruise control. CC is boring! I enjoy too much accelerating, decelerating, doing multiple double clutch heel-toe downshifts, etc... that I wouldn't want to put the car on auto pilot. If that were the case, I might as well have gotten an automatic.

... And yes, I too can get good MPG on long highway stretches. When I drove it back from North Carolina, the DIC average showed 32.4 MPG. In reality, it was 28.5, still pretty good. Remember these cars are EPA rated at 19-28. If you get 35, you're either reading your MPG on the DIC, which is over-estimating it by about 10%, or driving like a saint, which is good for you but difficult to achieve for most mortals, or most likely a combination of both. The EPA test is already set up under unrealistic conditions. Are you driving even more unrealistically than that?

True, these cars can get decent MPG when you're very easy on the throttle, but under these conditions your acceleration won't match those of my wife's 2006 Civic, and she can get 40 real MPG (i.e. not DIC MPG) on the highway. When I have some real fun with mine, I average 12-13MPG.

 

My extremes have run from a low of 6.8 MPG - running for 2 hours at Texas Motor Speedway (full tank and only 143 miles later and it was bone dry), to a tad over 31 on the highway at 70 MPH (speed), flat interstate, no wind, good road and 35 psi in the tires.

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It's like a golf score, the lower it is, the more fun you're having.

 

Correct me if I'm wrong, but doesn't the DIC display current MPG and not average for the tank? Sure I see 30's all the time cruising the freeways and high teens, low 20's around town. Real fill up average for a long trip, miles divided by fill-up gallons, closer to 24-25 mpg. Toss in a run through the back roads or an autocross and average falls to 16-17. Last 5 fill-ups (all short runs, no long trips) 19.4, 20.5, 22.4, 20.6, 16.2 (after autocross with 2 drivers - 5 runs each). I drive fairly aggressively around about the 85-percentile. Probably will be in the high teens for the next couple of tanks since I just installed a B&B PRT exhaust system

 

The DIC provides two MPG reading. One is real time, what you are getting at that moment. It is all over the board depending upon hills, throttle, etc, etc. The other is the avg MPG that you have gotten since the last time the "Avg MPG" was reset. It has nothing to do with a tank of gas, just what has been happening since it was last reset.

tom...

 

Your individual mileage will vary greatly with use. I only get about 16mpg if I only drive to work which is 3.5 miles each way with 12 lights. Mix in a trip with a bit of highway and it will go to 22 or so. Cruise setting on an extended road trip and I can get 27-31 mpg depending on where you are in the country and direction of travel. For instance traveling east you have the wind behind you and vise versa. Also, in the west humitity is lower so the air in the chamber heats up more which improves mileage. Gearing comes into play also. Finally, I have noticed that putting on the cruise does bump up mileage a notch or two just because the computer and optimize and run a lower margin for transient response.

 

Everything that I have heard has it the other way. Under cruise the computer will maintain speed up hills, and then keep the speed steady going down hill. Without cruise you will normaly loose speed going up hills (which helps milage) and then you can glide down hill again saving gas. Cruise control will force you to maintain speed under all conditions which is not good for milage.

By the way, have an '04 conv with automatic. Last June drove from Austin TX to Las Vegas and back, about 3000 miles, and got 30.5 overall.

tom...

 

what kind of CD's do you all listen to... with AC/DC my mileage tends to drop in the single digits...

 

I pop in some Michael Bolton for that same effect.

Anything to get me to my destination faster and end my suffering. They should play his crap in ambulances.