MPG E60 vs. E90 -- What??
Thread Starter
Members
Joined: Dec 2010
Posts: 37
Likes: 0
From: Texas
My Ride: Mine: 2005 545i Sport Pkg, Black Saphire/Black, Nav, Chrome Wheels ---------- Wife's: 2007 335i Sport/Prem Pkg, White/Auburn, Nav
We took a road trip (about 3 hours) in the 545i and I was so impressed that, with the cruise set at 73 mph, I got 30 mpg! Then the following week we took another road trip but this time we went in my wife's 2007 335i and at the same speed I couldn't get it to go over 28 mpg! So what gives? I thought the E90 should've had better mpg. Is it the twin turbos?
Senior Members
Joined: Oct 2009
Posts: 1,380
Likes: 4
From: Indiana, USA
My Ride: 2007 530xi: Sport, NAV, PDC, HUD, Cold Wthr, CA, Logic 7, HD Radio, SAT, Custom NCS coded options 2008 535xi: Sport, Night Vision, NAV, PDC, HUD, Cold Wthr, CA, Logic 7, SAT, Custom NCS coded options, Rear Seat Heat Retrofit, Passport 9500ci
Model Year: 2008
Engine: N54
We took a road trip (about 3 hours) in the 545i and I was so impressed that, with the cruise set at 73 mph, I got 30 mpg! Then the following week we took another road trip but this time we went in my wife's 2007 335i and at the same speed I couldn't get it to go over 28 mpg! So what gives? I thought the E90 should've had better mpg. Is it the twin turbos?
I'm not sure the turbos are doing anything at cruising speed on the highway.
Thread Starter
Members
Joined: Dec 2010
Posts: 37
Likes: 0
From: Texas
My Ride: Mine: 2005 545i Sport Pkg, Black Saphire/Black, Nav, Chrome Wheels ---------- Wife's: 2007 335i Sport/Prem Pkg, White/Auburn, Nav
True (on the turbos) -- I was just thinking that the difference in the engine might make a difference.
Someone mentioned to me that it's the aerodynamics of the 5 Series. And that the valvetronic engine helps it in steady, state highway cruising.
Sounds like a deal to me!
Someone mentioned to me that it's the aerodynamics of the 5 Series. And that the valvetronic engine helps it in steady, state highway cruising.
Sounds like a deal to me!
Senior Members
Joined: Jul 2008
Posts: 295
Likes: 0
Non-turbo V8 Valvetronic engine at 73mph is pushing less revs on 6th gear than the straight 6 twin-turbo, no?
I don't believe the aerodynamic explanation too much - it's bigger, heavier and more bulky.
Still, 2MPG might be just a small calculation aberrancy. Pretty good mileage anyway. You can get over 43 on a diesel
I don't believe the aerodynamic explanation too much - it's bigger, heavier and more bulky.
Still, 2MPG might be just a small calculation aberrancy. Pretty good mileage anyway. You can get over 43 on a diesel
Senior Members
Joined: Feb 2008
Posts: 337
Likes: 1
From: NYC
We are talking about the same course, right? Was a little unclear in your OP.
Are there gearing differences between the two cars? All things equal the lighter car should get better gas mileage, but the valvetronic system eliminates pumping losses at low throttle openings (consistent with highway driving), so who knows - anything's possible. Normalizing driving styles is also pretty hard, and it's pretty easy to dip into that 335i's power without realizing it.
That said, I've NEVER gotten 30mpg on the highway in my car on any sustained trip. Then again, I've never driven at a flat 73mph in any sustained way, either.
Are there gearing differences between the two cars? All things equal the lighter car should get better gas mileage, but the valvetronic system eliminates pumping losses at low throttle openings (consistent with highway driving), so who knows - anything's possible. Normalizing driving styles is also pretty hard, and it's pretty easy to dip into that 335i's power without realizing it.
That said, I've NEVER gotten 30mpg on the highway in my car on any sustained trip. Then again, I've never driven at a flat 73mph in any sustained way, either.
Thread Starter
Members
Joined: Dec 2010
Posts: 37
Likes: 0
From: Texas
My Ride: Mine: 2005 545i Sport Pkg, Black Saphire/Black, Nav, Chrome Wheels ---------- Wife's: 2007 335i Sport/Prem Pkg, White/Auburn, Nav
Yes,...it was the same course, same driver, and I reset the trips when I started.
As far as the average mpg, it went between 29-30 mpg on the trip computer. I guess my thing is that I thought there would be a significant difference between the 2. I never thought that the 545i would equal it or come close to it. Now in the city,...that's a different story!
As far as the average mpg, it went between 29-30 mpg on the trip computer. I guess my thing is that I thought there would be a significant difference between the 2. I never thought that the 545i would equal it or come close to it. Now in the city,...that's a different story!
Contributors
Joined: Nov 2010
Posts: 525
Likes: 0
From: North Carolina
My Ride: 535i
