Yes, the C7 is capable of 40+ MPG going 70mph! Proof!
08-21-2013, 09:47 PM
#41
Team Owner
The Highway EPA rating in Eco mode is 30mpg. Here's what the car has to do for the Highway cycle:
That's a fair amount of speed variation. Certain states that combine flat roads with low traffic might be able to get highway conditions that are much closer to a steady state 70mph.
If the car was traveling on the interstate on fairly level ground for the 26 miles and was able to maintain constant speed close to the average with minimal acceleration, the 40.5 isn't too far fetched.
In most cars it's also possible to "game" the gauge somewhat by resetting the gauge at an opportune time. In my C5 I'm pretty sure I can reset the average speed and average fuel economy counts separately, leading to the possibility of me driving in a fashion to average 70 mph, then reset fuel economy average gauge, let off the gas for 2 seconds and coast bringing the average way up, then taking the pic. Not saying they gamed the gauges, just pointing out it's a possibility.
Either way it's pretty impressive.
That's a fair amount of speed variation. Certain states that combine flat roads with low traffic might be able to get highway conditions that are much closer to a steady state 70mph.
If the car was traveling on the interstate on fairly level ground for the 26 miles and was able to maintain constant speed close to the average with minimal acceleration, the 40.5 isn't too far fetched.
In most cars it's also possible to "game" the gauge somewhat by resetting the gauge at an opportune time. In my C5 I'm pretty sure I can reset the average speed and average fuel economy counts separately, leading to the possibility of me driving in a fashion to average 70 mph, then reset fuel economy average gauge, let off the gas for 2 seconds and coast bringing the average way up, then taking the pic. Not saying they gamed the gauges, just pointing out it's a possibility.
Either way it's pretty impressive.
So, that means if I get 29 MPG on the highway I'm within the EPA Fuel Economy Estimates for my Z06.
08-21-2013, 09:51 PM
#42
Racer
08-21-2013, 09:58 PM
#43
Many of us do. These cars are amazing road trip vehicles due to their extreme versatility. The new features on the C7 have taken that versatility to the next level. With the Z51 package and MSRC I can have a truly track-capable car that I can then, with the turn of a ****, daily drive in comfort and get 35+ mpg on the highway. That's truly amazing. Gone are the days of having to sacrifice drivability for performance.
08-21-2013, 10:02 PM
#44
mileage
Two years ago in my 2002 vet coupe loaded with luggage and wife took a7400 mile month long trip across the U.S. From the time I left the driveway to the time I got back we averaged 30.0 mpg. Spending one week in Seattle and one week in the smokies. both very congested. Drove 70-75 most of the way. At one point going to Roswell ave 34mph at 80 mph with the tires going into the 40"s due to the heat. Never on cruse, Keep your foot completely off the gas on downhill grades,
08-21-2013, 10:08 PM
#45
Team Owner
I did spend a little over three years stationed in Wichita in a nice cool 60 degree missile silo.
Last edited by JoesC5; 08-21-2013 at 10:11 PM.
08-21-2013, 10:10 PM
#46
Many of us do. These cars are amazing road trip vehicles due to their extreme versatility. The new features on the C7 have taken that versatility to the next level. With the Z51 package and MSRC I can have a truly track-capable car that I can then, with the turn of a ****, daily drive in comfort and get 35+ mpg on the highway. That's truly amazing. Gone are the days of having to sacrifice drivability for performance.
Like most, I did not buy my Corvette because of its excellent fuel mileage but, like most who take theirs for multi-day road trips (I've done two 4,000 mile trips), I appreciate its highway cruising efficiency.
08-21-2013, 10:17 PM
#47
Team Owner
Many of us do. These cars are amazing road trip vehicles due to their extreme versatility. The new features on the C7 have taken that versatility to the next level. With the Z51 package and MSRC I can have a truly track-capable car that I can then, with the turn of a ****, daily drive in comfort and get 35+ mpg on the highway. That's truly amazing. Gone are the days of having to sacrifice drivability for performance.
08-21-2013, 10:20 PM
#48
Intermediate
Member Since: Jul 2013
Posts: 43
Likes: 0
Received 0 Likes
on
0 Posts
The EPA fuel Economy Estimates on the window sticker are not "cast in stone" numbers. On my 09 Z06 in BIG numbers is says Highway MPG 24, Then in small numbers it says Expected range for most drivers 19 to 29 MPG
So, that means if I get 29 MPG on the highway I'm within the EPA Fuel Economy Estimates for my Z06.
So, that means if I get 29 MPG on the highway I'm within the EPA Fuel Economy Estimates for my Z06.
The 5 cycle method combines
FTP75 aka LA4 "city" cycle
cold FTP, similar to an FTP but performed at 20F instead of 75F
US06, the high speed cycle
SC03, the cycle with air conditioning
Highway, with drive cycle depicted above
Basically, they run all those tests and punch the numbers into a spreadsheet which spits out an adjusted number. Or the 5 cycle value can be derived by doing FTP and highway only, and using a different calculation. It's pretty complicated.
08-21-2013, 10:36 PM
#49
Team Owner
Highway fuel economy (and city for that matter) is calculated according to the 5 cycle method, not by the raw unadjusted score on the highway cycle alone. It hasn't been calculated that way for decades.
The 5 cycle method combines
FTP75 aka LA4 "city" cycle
cold FTP, similar to an FTP but performed at 20F instead of 75F
US06, the high speed cycle
SC03, the cycle with air conditioning
Highway, with drive cycle depicted above
Basically, they run all those tests and punch the numbers into a spreadsheet which spits out an adjusted number. Or the 5 cycle value can be derived by doing FTP and highway only, and using a different calculation. It's pretty complicated.
The 5 cycle method combines
FTP75 aka LA4 "city" cycle
cold FTP, similar to an FTP but performed at 20F instead of 75F
US06, the high speed cycle
SC03, the cycle with air conditioning
Highway, with drive cycle depicted above
Basically, they run all those tests and punch the numbers into a spreadsheet which spits out an adjusted number. Or the 5 cycle value can be derived by doing FTP and highway only, and using a different calculation. It's pretty complicated.
08-21-2013, 10:36 PM
#50
Burning Brakes
Member Since: Jan 2005
Location: Miami & Naples, FL
Posts: 796
Received 433 Likes
on
110 Posts
Unmodified C8 of the Year 2021 Finalist
40+ MPG is possible......with a V4 engine
Don't forget that in 7th gear with only 4 cylinders sipping fuel, you can acheive 40+ MPG.
This is great technology.
No guzzler tax for us !!!
This is great technology.
No guzzler tax for us !!!
08-21-2013, 10:38 PM
#51
Team Owner
No gas guzzler tax on my 505 HP C6 Z06. Sounds like they also had great technology back in 2005 when GM released the 2006 Z06.
08-21-2013, 10:56 PM
#52
Le Mans Master
08-21-2013, 10:59 PM
#53
Le Mans Master
08-21-2013, 11:05 PM
#54
Team Owner
Every time I take my 64 coupe(15-16 highway) on a 250 mile lunch cruise, I know that lunch is going to cost me twice as much than if I had driven my Z06.
08-21-2013, 11:13 PM
#55
My '82 Silverado with stock 350 gets, maybe, 10 mpg whether going uphill, downhill or flying off a cliff 
Still fun to drive part of the time and makes driving the Vette more fun!
Still fun to drive part of the time and makes driving the Vette more fun!
08-21-2013, 11:23 PM
#56
Le Mans Master
08-22-2013, 09:58 AM
#57
Safety Car
I certainly care about mpg. I have over 90k miles on my 07. I make many ~230 mile trips between Louisiana and Texas. I would likely see 35 mpg in the new C7 in eco mode which would be about 6 to 7 mpg more than I make now.
08-26-2013, 11:46 PM
#58
Burning Brakes
Oho! Here's a fascinating little tidbit from the newly-published Owner's Manual that helps explain high average MPG displays:
"Best Average Fuel Economy: Displays the average fuel economy, the best fuel economy over the selected distance, and a bar graph showing instantaneous fuel economy. Press p to change the selected distance."
So you can tell the system to calculate MPG over a 26-mile range (for instance) and it will continually recalculate a rolling 26-mile average, displaying the figure for the best 26-mile stretch you have hit. Much different and much more impressive than total average MPG (which is also separately available).
"Best Average Fuel Economy: Displays the average fuel economy, the best fuel economy over the selected distance, and a bar graph showing instantaneous fuel economy. Press p to change the selected distance."
So you can tell the system to calculate MPG over a 26-mile range (for instance) and it will continually recalculate a rolling 26-mile average, displaying the figure for the best 26-mile stretch you have hit. Much different and much more impressive than total average MPG (which is also separately available).
05-07-2014, 07:23 PM
#59
4th Gear
Member Since: May 2014
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
It is possible. I had my Green C7 out to Vegas to escort a friend who was towing a car back. We were following him at 60mph in traffic, LV to Baker. A mix of up hill and downhill. Just for grins, I put it in eco mode and stayed in 6th and 7th gears. Did this for 75 miles including some stop and go. I averaged 40.7mpg in that stretch - then I got bored.
