rmorin1249

Just returned from a 600 mile round trip from Hagerstown MD to Ocean City MD to attend the big Corvette show. I had my Range on for the entire trip. Most of the miles, about 500, were highway driving 60 - 80 mph. About 100 miles we're cruising around in Ocean City. I averaged 30.6 mpg for the entire trip without ever using V4 mode. I believe this exceeds the advertised highway MPG that I assume includes using V4 mode. So, I ask again who needs AFM? Not me.

owc6

It sounds like you got lost somewhere and added two hundred miles to the trip.

Where else did you go?

rmorin1249

Rehobeth, Assateague Island and Berlin.

mschuyler

Nobody needs AFM. GM needs AFM to pass the CAFE standards. It's just like the 1-4 shift. No Corvette driver needs it. The Corporation does.

owc6

Nice!

Drove my '05 on the beach on Assateague. Way back in '05.

dvilin

Don't need it and have never used it.

R50THC5

I HATE IT....

joemessman

I have never noticed any real measurable difference in my mileage after disabling AFM. At most in a couple of test runs it was about a half a mile per gallon going from Lake Havasu to Las Vegas and back, but that could have been due to wind variations, etc.

Corgidog1

Having a stick, V4 is a non issue for me.

Mike Mercury

yep. No one "needs it"

But AlGore and his cult gets-off by forcing these things on to others.

krwunlv

Same, OC MD to Frederick I was averaging 30 ish. Not bad IMO, esp with the aero mods I have on that will reduce MPG.

Hi neighbor!

Vetteman Jack

BLACKCREEK

I did a recent road trip to key west. Once you hit Largo you fall in line and can only average 45 to 50 on the run to key west. I have a manual and turned on the afm just to play. In 5th gear on dead flat sea level road with the cruise control set to 50 switching the afm off would routinely drop the readout 2 or 3 mpg. I left it on for the trip through the islands and averaged 39 mpg (with a slight tailwind) from key largo to key west. I don't use afm much around town or blasting down the freeway because it is constantly shifting in and out of v4. I was however really impressed with it on the slow drive through the keys.

PegasusCapital

You only need AFM if you want to screw-up your A8 tranny.

mschuyler

Fair enough, but it's pretty good anyway. On a 1000 mile road trip I get about 29 mpg. If I used AFM I'd get about 32 mpg. The difference in cost is about $10.00. If gas mileage is a priority for you you'd get a Prius. Nothing wrong with wanting good mileage, but I doubt anyone says, "I'm getting a Corvette because it gets such good mileage."

Highplains

In May, averaged 29.9 MPG for a 4000 mile road trip. Used the Range the entire time. 2016, A8 Stingray.

KemahGT

JerryU

Exactly! In fact folks may not need start/stop but it's coming as GM needs all the help they can get.

We'll see what engine is in the C8 but my bet is it will be a turbo small CID for the same GM reason. The current Ford GT is a 3.5 Liter V6 with dual turbo's achieving 647 hp! Not bad!

In fact would love to have the F1 KERS (Kinetic Energy Recovery System.) It weighs about 60 pounds with battery and gives 160 hp for about 10 seconds. Could be used when accelerating from a stop as that is by far the worst mpg. Even in normal street driving it could be used until you reach cruising speed as you would not need 160 hp so double the time should be possible. Then like F1, the electric motor turns into generator to recover some of the braking energy to charge the system.

On average about a 1/3 of the energy that gets to the rear wheels winds up going into braking! The internal combustion engine is very inefficient. Only about 15% of the energy in gasoline gets to the rear wheels!

Patman

Nobody really NEEDS AFM, as these engines can still get amazing mileage even without it. However, if the technology is there, why not utilize it? I certainly like the idea of saving a few bucks on gas if I'm on a long highway trip. It's doing no harm to me, I have 8700 trouble free miles on my A8 and I let it go into V4 mode all the time. I know, nobody buys a Corvette for gas mileage, bla bla bla, I've been hearing that same thing for years. But gas is pretty damn expensive up here in Canada, it's often over $1.50 PER LITER for premium gas. So that's over $100 to fill the tank. I already spend over $500 a month on the 3 cars in our household, so any savings I can get, I will take it.

Spinny

Perhaps I am just unlucky, but I have seen a 2 MPG drop since installing a Range. This has been in general "around town driving". I have not taken it on a road trip yet.