vbdenny

You have to remember than even in the V-4 mode, you still have half the power which is 230hp which is more than most cars.

TPAJETSKI

I certainly could be wrong but I thought power in V4 mode was like 150hp???

Maxpowers

^^^^

Yeah - I'd guess in V4 mode your getting much less than half of the 460hp due to the drag of the other 4 cylinders.

Dif

When mine was brand new I could tell when it went from V8/V4/V8.
Around 500 miles it became hard to notice unless I'm paying close attention.
As for Eco mode, I haven't seen much difference unless driving on a Long trip with flat roads.
I'm usually in Tour or Sport and use Auto and Paddles about 50/50.
Highway driving it's in Auto and stays in V4 quite a bit over 60 mph.
At 80 mph or more, it stays in V4 even going uphill unless it needs more throttle.
Just my experience

DickieDoo

V4 mode works best when going downhill or having the wind at your back. Otherwise the improvement is not that significant... about 2 mpg.
So going downhill with the wind at your back, you would see a 5-7 mpg improvement...

R8Z51

So I pulled the fuse for the NPP exhaust system and now I can definitely hear when the car goes into V4 mode. In eco mode, it shuts off the cylinders more often than in touring mode. I can't believe how long it'll stay in V4 mode even when under load. Learn something new everyday with this car!

hisvett

The only way I know the car goes into V4 is hearing the exhaust valves snap shut and everything gets really quiet. The first couple of K miles, I would turn the **** to "Eco" thinking it would help with the mileage; now some 40K miles later I just drive it in the default Touring mode....don't notice any difference in fuel consumption.

When comparing mileage, remember the Base cars have slightly taller gears than the Z51's and GS cars.

Vette_Pilot

Wouldn't it be better if it was a V6 mode instead of V4??

drobbins

as I understand it, that won't work
has to do with balance of the engine
really doesn't balance properly in V4, worse in V6

aj98

In my 14 m7,gotta be in 3rd (or higher) and maintain a relatively constant speed for about 1/4 mile before eco kicks in. Touch the clutch, back to v8 mode you go.

Effectively, around town, eco doesn't do much.

LT1 Z51

I use ECO on the Freeway and on country roads (basically anywhere I can use cruise control).

Going 60 MPH in 6th gear I got 33 MPG.

The display for V4 Mode is on the screen which shows you instantaneous fuel economy. I keep this one up in my RPM display all the time.

tcinla

Are C7 volumes high enough that including AFM makes a difference to fuel economy requirements put on GM by Uncle Sam ?

I didn't buy a corvette with fuel economy in mind. In fact, I resigned myself to having to spend more on gas as the trade off (not knowing about AFM prior to buying) and I was OK with that.

obxchartercaptain

I agree with you about not buying a vette for fuel economy....HOWEVER, on a long trip with nothing to do but CRUISE between fuel stops/rest stops... I can't see the harm in saving fuel.

C7Joy

I don't bother much with eco, but I still does seem to work very well, smooth going to V4 and back to V8. I haven the bothered to study what my fuel savings might be but see some good numbers up on the DIC. With the terrain around here coupled with the way I drive, V4 would not show up much anyway!

felkebg

Mine goes into V4 mode in most if not all driving selections but even under cruise control it will go back to V8 climbing even moderate slopes. It will, however, maintain V4 under the right conditions even at 80 + mph

vbdenny

Just got a Range AFM device. Simple OBDII plug in. Never goes into V-4 mode. I like that.

tcinla

Have any diagnostic codes been thrown ? Some people with the Range device have reported codes.

Smooth9883

This. I notice it on my 16 A8 and on my 16 Yukon. Others have told me they can't feel a difference but I can tell when I'm paying attention.

DickieDoo

I disagree, around town, ECO is most annoying... it does that well and makes me glad i have an M7.

J Tilgh

What is up with all the noise under the hood. I know it is the ATM system doing its thing, but I understand the 2015 + do not have that weird sound/