MPG question

[Count Mackula]

Just how the hell do we get such great MPG with nearly 400 hp?
I don’t get it. This car gets better MPG than all the previous cars I’ve owned.
Better than NA V6, I4, turbo I4, V8s, etc, and quite possibly better than any car I have rented/driven.
Back in late June, I was driving back from Vegas and decided and to measure my trip mpg and try to get the best MPG possible. I reset it RIGHT AFTER Henderson (it’s right next to Vegas for those that don’t know).

I left around midnight because there’s not much traffic and cruised at approximately 70 MPH. I probably depressed either pedal once or twice and the AC on 70 degrees.

When I arrived in Barstow, I stopped measuring the MPG and snapped a picture of the screen and got around 42 MPG. I was stunned.
I thought it was a fluke and tried it again the next week and the best I got was around 38 (but I had to punch it a few times to get passed truckers). But still… that’s better than my friends I4 when they’re just cruising.

I did this drive in various cars and never achieved gas mileage like this car does. How the hell does BMW/Toyota pull this off? What is it? Any insight. (I’ll try to attempt it again this weekend and see if I can get close to 40 MPG again)

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[freeform911]

I have NEVER came close to that...
I average 17 mph but most of my driving is in town...I also have a very difficult time with not putting my foot in the Supras ass...just sayin...

Steve

 

[digicidal]

I regularly do around 30mpg in mine when I drive out to Pahrump, which is a bit similar to your NV-CA run described (i.e. hill climb then descent... so quite a bit worse at first, then insanely high on the back side of the pass). Of course, I've also never gone as slow as 70mph (unless there's a HiPo in the area). Depending on the time of day it's 85mph or above until I hit town and I still see 28-30 mpg on that run.

It definitely does get great highway mileage... but in town it's worse than any I4 I've ever owned (all Honda's). Probably could get as high as 20mpg if I never put my foot in it... but I find 18-19 mpg in town is my average.

In answer to the OP question... it's because you're only using 5-10% of that HP... try doing that same run at 140mph and you'll be lucky to get 10mpg.

 

[Count Mackula]

Oh yeah, mpg in town is rather shitty for me too. Since I tend to have a lead foot around town. But Highway miles is fantastic!

I forgot to mention that the Vegas-Barstow drive has an elevation change of 120 feet I think. So it’s pretty flat with hills here and there.
But still… I don’t think I did 35+ mpg in any car before.

 

[Deleted member 4362]

44 on the run back home from Goodwood for me. I get 28-33 in the week on a 10 mile commute.

My 718 would get around 42 on a similar run.
FK2 Type R once got 48.
Wife’s Civic Turbo would do 56. Her i30N does about 38.

On a consistent cruise, modern engines are incredibly efficient. Obviously helped by the advances in manufacturing tolerances, materials, tribology, and oils.

 

[digicidal]

I haven't in any car that was fun... but in my '92 Civic with the 1.5L I4 I could hit 50mpg on highway runs to CA and was regularly in the low 30's in town. That was with a 5spd manual... if I'd had a 6th gear it would have been even better highway.

 

[Escapist]

BMW engines are highly efficient. This car is also neutered from all hell from factory. Which is why you can make such big power from simple bolt-ons and a tune. Funny enough, my mpg's actually went up with my tune, disabling the burbles helped with that.

 

[Drakov]

Drove from Bay Area CA to LA area and got 33mpg. With Avg speed of 67mph according to the trip info.. combined hwy and city I avg 27 mpg.

 

[puzzled]

Wow.. I can only get like 28.7mpg during my weekend drives with several launches and several more launches..

 

[SuupYota]

Yeaaaaa, I get about 12...hahaha

 

[Count Mackula]

Good to know I’m not the only one getting great fuel economy. I was thinking perhaps my mpg gauge is busted or just some weird variable I wasn’t aware of.

Guess I haven’t driven many newer cars. ? This is my first BMW car, so I was thinking perhaps this is something BMW inherently does.
Thanks for the feedback again guys.

 

[Zupra1776]

It's pretty good for the power range. My STI was absolutely abysmal. I got 19mpg best case scenario and realistically about 17mpg with a heavy foot...and that was slow AF in comparison. Even in spirited sport mod I get 23+ mpg in the Supra, and have easily gotten 27+ when in comfort.

 

[zrk]

I live in Chicago and typically get around 15-17. When I take it out for longer drives it’s more like 25.

cruise days it’s more like 8.

 

[type-964]

I’m amazed at the restraint some of you can show. 30MPG…I’m either doing something very wrong or very right. I’ve never really checked but I bet my norm is 12-16MPG.

 

[freeform911]

I’m amazed at the restraint some of you can show. 30MPG…I’m either doing something very wrong or very right. I’ve never really checked but I bet my norm is 12-16MPG.

You're driving it they way you're supposed to?..
Definitely doing nothing wrong...

Steve

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