Why is my car only getting 14.4mpg?

[NYG]

Originally Posted by jpy1980

14.5 is pretty good if you track. My last track day I got about 70 miles to the full tank. That was about 5mpg!

Mind you this was a full track day with autocross as well.

I get 5 mpg on the track tops.

[2011zx10R]

Originally Posted by jpy1980

Haha nice!

The lower the number, the better it is! It is a badge of honor! Means I'm driving the car the way it was supposed to be.

When it's low, just fill 'er up!

Originally Posted by jpy1980

Haha nice!

The lower the number, the better it is! It is a badge of honor! Means I'm driving the car the way it was supposed to be.

When it's low, just fill 'er up!

Badge of honor; I like that hahahah

[Paisano]

Originally Posted by NYG

I get 5 mpg on the track tops.

5 MPG on track is impressive...I got down to 3.9 / 4.1.

All jokes aside, I'm averaging 17.8 to 18 MPG with a 6-speed on my M4 and driving it like it's stolen. 80% city 20% highway and currently at 17,500 km.

Curious as to how people are averaging 14-15 MPG?

[jpy1980]

Originally Posted by 2011zx10R

Badge of honor; I like that hahahah

Haha it is! Visa and MasterCard will thank you!

[jpy1980]

Originally Posted by Paisano

5 MPG on track is impressive...I got down to 3.9 / 4.1.

All jokes aside, I'm averaging 17.8 to 18 MPG with a 6-speed on my M4 and driving it like it's stolen. 80% city 20% highway and currently at 17,500 km.

Curious as to how people are averaging 14-15 MPG?

This is probably due to tire pressures being off, maintenance schedule, braking habits, city vs freeway driving, etc.

Honestly MPg isn’t a real metric for me. It’s SPg hahaha smiles per gallon.

[Paisano]

Originally Posted by jpy1980

This is probably due to tire pressures being off, maintenance schedule, braking habits, city vs freeway driving, etc.

Honestly MPg isn’t a real metric for me. It’s SPg hahaha smiles per gallon.

Sir, I will be commandeering SPg thank you very much for the introduction to this new concept.

[Matteo88]

i average 25-26mpg pretty consistently but i do a lot of highway.

also should note i'm a huge nerd and have tracked my own fuel mileage on every fill up over the past 11 years (about 500 fill ups) and note that the F8X is pretty honest in what the computer reports back. on average it is 0.25L/100km "optimistic" which means it's reading 0.25L/100km better than what i am calculating upon fill ups. this translates into only 2.7% which is pretty close.

i'm thoroughly impressed with the efficiency of this engine given the performance. i'm getting better fuel mileage than i did with my genesis 3.8GT with far better performance (and 3x the price lol). and i often drive like an asshole but usually efficiently in the sense that i won't boot it to a red light only to hammer the brakes.

14.4 seems really low. try driving like a grandma for a few tanks and see if you can do better. put it into the most efficient mode and let the transmission change all your gears.

[jbed]

Per a avg calc in dash:

14-14.5 in sport plus responsiveness w gear change in position 2 for dct

17-18 in sport and position 1 for dct

20ish at slow highway speeds (under 70 mph) using 7th gear in dct.

So 14ish is totally possible if you aren't shifting like a bus driver

[EricSMG]

I just picked up my second F8X. This time an M4 ZCP DCT (coming from an M3 ZCP 6MT) and I'm averaging 15 in the city with a heavy foot and Sport+ exclusively. It may rise a little but not much.

So yeah, I don't think 14.4 is really that bad assuming you drive the car hard in Sport+.

[agentrnge]

Originally Posted by Matteo88

i average 25-26mpg pretty consistently but i do a lot of highway.
...
and i often drive like an asshole but usually efficiently in the sense that i won't boot it to a red light only to hammer the brakes.

+1 I drive like an asshole when possible, but efficiently as possible.
I get like 21 mpg avg driving moderately hard most of the time, 50% commute putzing around. 5-15% really open road blasts.

14 sound problematically low, even with bad traffic. Fuel consumption at idle is probably very low in modern cars. Not sure about the S55, but the v8 in the G30 M550i uses not quite a liter per hour at idle according to this post:
https://www.bimmerfest.com/forums/sh....php?t=1301065
Dunno about other environmental effects such as blasting AC, and every radiator fan going full tilt while sitting in a 120F road, vs windows down on a nice 60F day.

[Smeargle]

This thread is crazy, on my 6spd m3 I was getting about 18.5 mpg on a crazy flame tune daily driving about 19k miles and then I reset it when I went back to stock and now I'm getting about 19.3(after about 4K miles). I shift pretty high usually in regular driving(3-3.5) so I'm very confused how you guys are getting such low mpg.

[M3Xris]

After two weeks of ownership I'm averaging 17 mpg. I drive in S/C/C in manual mode.

[MrSlickk]

Alrighty let me give my closing statement. It's been a month of ownership now first 2 tanks were 14 mpg city driving only. The more recent ones are with moderate-hard driving 18mpg mix of city and highway. Let me just add that after a month with this car I have no complaints. It's all around perfect

[EricSMG]

Originally Posted by Smeargle

This thread is crazy, on my 6spd m3 I was getting about 18.5 mpg on a crazy flame tune daily driving about 19k miles and then I reset it when I went back to stock and now I'm getting about 19.3(after about 4K miles). I shift pretty high usually in regular driving(3-3.5) so I'm very confused how you guys are getting such low mpg.

Because you're driving it like a grandpa. If you think shifting at 3.5k rpm is "pretty high" then that essentially ends this thread. I drive with the rpms no lower than 3k rpm 95% of the time as that's where full boost comes in. The motor sucks below 3k.... may as well drive a regular car.

Plus, in my experience, most people don't know how to actually calculate real world mpg (not saying you, necessarily). For example: you can say "hey look, I sent 90 miles in the top 1/4 tank and so if I multiply that by 4....". No. There is only ONE way to calculate mpg: divide miles driven by gallons poured. Period. If everyone posting in this thread were to actually do that I guarantee many of these optimistic numbers would come down significantly.

I've been having this same discussion for 16 years starting at BimmerForums (36M days) then to M3F (46M days) then to M3P (E90M days) and now BP (F8XM Days). Same story, every time. You get realistic people and dreamers.

Originally Posted by agentrnge

+1 I drive like an asshole when possible, but efficiently as possible.
I get like 21 mpg avg driving moderately hard most of the time, 50% commute putzing around. 5-15% really open road blasts.

14 sound problematically low, even with bad traffic.

21mpg as an overall average is very hard to believe, assuming you actually keep the motor in boost often, are not cruising on the freeway heavily and don't live in Kansas (rural areas).

I'm on my second F8X and I'm getting exactly the same mpg in the second one: ~16mpg, mostly "in town" driving, heavy foot, Sport+ exclusively, frequent redlining, motor always in boost. There is nothing problematic about my numbers - they are real world for someone who uses the 444hp regularly.

[Smeargle]

Originally Posted by EricSMG

Because you're driving it like a grandpa. If you think shifting at 3.5k rpm is "pretty high" then that essentially ends this thread. I drive with the rpms no lower than 3k rpm 95% of the time as that's where full boost comes in. The motor sucks below 3k.... may as well drive a regular car.

Plus, in my experience, most people don't know how to actually calculate real world mpg (not saying you, necessarily). For example: you can say "hey look, I sent 90 miles in the top 1/4 tank and so if I multiply that by 4....". No. There is only ONE way to calculate mpg: divide miles driven by gallons poured. Period. If everyone posting in this thread were to actually do that I guarantee many of these optimistic numbers would come down significantly.

I've been having this same discussion for 16 years starting at BimmerForums (36M days) then to M3F (46M days) then to M3P (E90M days) and now BP (F8XM Days). Same story, every time. You get realistic people and dreamers.

21mpg as an overall average is very hard to believe, assuming you actually keep the motor in boost often, are not cruising on the freeway heavily and don't live in Kansas (rural areas).

I'm on my second F8X and I'm getting exactly the same mpg in the second one: ~16mpg, mostly "in town" driving, heavy foot, Sport+ exclusively, frequent redlining, motor always in boost. There is nothing problematic about my numbers - they are real world for someone who uses the 444hp regularly.

I don't think there's any realistic way to be driving in NY traffic and be riding our gears longer than 3.5, or should I say a realistic reason too. If you notice I said "in daily driving" which is different from actually getting on it lol. I find it hard to believe that wherever you go you ride out each gear to above 5k.

[djMpower]

Originally Posted by Smeargle

I don't think there's any realistic way to be driving in NY traffic and be riding our gears longer than 3.5, or should I say a realistic reason too. If you notice I said "in daily driving" which is different from actually getting on it lol. I find it hard to believe that wherever you go you ride out each gear to above 5k.

I'm not the guy you responded to, but I'll chime in anyway due to your last point. Yes, I'd agree with you that in NY it doesn't seem feasible. Here in LA (CA) though, I'm also like EricSMG and never keep the car below 3-3.5. Happy to make a video of my dash as I drive around if it comes to that, haha.

If you're wondering why, frankly because there's no power that low. Everyone that complains about turbo lag in these cars just doesn't know how to keep their engine in its power band. And I'll readily own up to the fact that from the outside looking in I definitely look like an asshole driver. Always significantly above the limit, always accelerating quickly, always braking hard. For context, my front pads and rotors went at 22k and I just had my rears done at about 26k. That's with 0 track days. But if you know what you're doing, even driving like that is still way below what the car can handle. I only ever give it 7-8 tenths tops.

Back to the topic at hand, when driven properly these things tend to get 15-16mpg. If you're getting above that then you're definitely grannying it. Sorry to break it to you guys. I can respect the reasoning, and I'm sure you're safer drivers for it, but it doesn't change that simple truth. All that said, I'm not here to encourage anyone to act like a lunatic on the roads. Some of us do, some of us don't. Let's just all enjoy our cars however we seem fit 'cause they're fucking awesome regardless.

[EricSMG]

Originally Posted by djMpower

I'm not the guy you responded to, but I'll chime in anyway due to your last point. Yes, I'd agree with you that in NY it doesn't seem feasible. Here in LA (CA) though, I'm also like EricSMG and never keep the car below 3-3.5. Happy to make a video of my dash as I drive around if it comes to that, haha.

If you're wondering why, frankly because there's no power that low. Everyone that complains about turbo lag in these cars just doesn't know how to keep their engine in its power band. And I'll readily own up to the fact that from the outside looking in I definitely look like an asshole driver. Always significantly above the limit, always accelerating quickly, always braking hard. For context, my front pads and rotors went at 22k and I just had my rears done at about 26k. That's with 0 track days. But if you know what you're doing, even driving like that is still way below what the car can handle. I only ever give it 7-8 tenths tops.

Back to the topic at hand, when driven properly these things tend to get 15-16mpg. If you're getting above that then you're definitely grannying it. Sorry to break it to you guys. I can respect the reasoning, and I'm sure you're safer drivers for it, but it doesn't change that simple truth. All that said, I'm not here to encourage anyone to act like a lunatic on the roads. Some of us do, some of us don't. Let's just all enjoy our cars however we seem fit 'cause they're fucking awesome regardless.

Yep. We're aligned here and enjoy our cars in the same way. The S55 is asleep <3k rpm, end of story. And don't even get me started on Efficient mode - completely ruinous to the car. Ultra laggy, no fun at all... doesn't even feel like an M car. (maybe that's how these dudes are getting such good mileage - Efficient + shifting at 3k rpm... sheesh... I'd slit my throat, haha).

And agree that no one should be reckless. There's a HUGE gap between driving this car hard and driving this car dangerously.

Originally Posted by Smeargle

I don't think there's any realistic way to be driving in NY traffic and be riding our gears longer than 3.5, or should I say a realistic reason too. If you notice I said "in daily driving" which is different from actually getting on it lol. I find it hard to believe that wherever you go you ride out each gear to above 5k.

I redline my car daily. And I am frequently in the 4-6k range in the first 4 gears.... all the time... that's where the motor is most happy and car most fun.

Sorry, but if you're shifting at 3.5k you're not experiencing the S55 - that's shifting just after you enter boost (3k). Trust me - put the throttle in Sport+ and keep the revs above 3k and you will see the light

Current mpg according to OBC = 14.9

[Smeargle]

Originally Posted by EricSMG

I redline my car daily. And I am frequently in the 4-6k range in the first 4 gears.... all the time... that's where the motor is most happy and car most fun.

Sorry, but if you're shifting at 3.5k you're not experiencing the S55 - that's shifting just after you enter boost (3k). Trust me - put the throttle in Sport+ and keep the revs above 3k and you will see the light

Current mpg according to OBC = 14.9

I feel like theres a misconception here. I drive in s+ all the time, my car was fbo stage 2 with a flame map so this mpg is literally factoring this in lol. I drive the car hard, I'm just not coasting around traffic at 4k rpm in an essencially straight piped f80. Especially in a 6spd car where 3k in 2nd is more often than not the speed of traffic.

[Bootiful_M3]

I'm seeing 22 average. I can get up to 25, and as low as 19 but I've never seen it under that.