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rimrock
05-07-2007, 08:38 AM
Does anyone have on-the-ground experience with the fuel economy for the 535i? I'm wondering if it's really all that frugal versus a 550i, especially with a heavy foot. Any replies would be greatlyl appreciated.

maug1
05-07-2007, 08:52 AM
I drove the car about 800 miles while doing ED (awaiting redelivery) and averaging about 85 mph I got 25.5 mpg per the cars computer. About the same as my '04 530.

SteVTEC
05-07-2007, 10:05 AM
If you're making more power, you'll be burning more fuel, regardless of engine size. All the elements are there on the 535i for it being reasonably more efficient than a 550i. It's lighter, the 3.0L I-6 has less friction, it still has a high compression ratio (thanks to direct injection) and with the turbos it'll have a higher average BMEP than the 4.8L V-8 when making the same amount of power which is also good for efficiency. And the turbos have special materials to allow them to handle extremely high exhaust gas temps which lets BMW run a leaner air-fuel mixture as opposed to a lot of other turbo engines that tend to run very rich (less efficient) with cooler EGTs in the name of turbo reliability and engine longevity.

lawbuz
05-07-2007, 02:44 PM
Just picked up my 2008 535i last week. I hit emply after about 315 miles. I don't know the tank capacity, so please compute gas mileage -- does not sound that great. I've driven on both highway and city.

chonko
05-07-2007, 04:27 PM
Just picked up my 2008 535i last week. I hit emply after about 315 miles. I don't know the tank capacity, so please compute gas mileage -- does not sound that great. I've driven on both highway and city.

16 gallons.
315(19.6 mpg) miles- that seems really low unless you were stuck in traffic most of the time.
What was you average speed?

Spyder
05-07-2007, 05:38 PM
Also consider that lawbuz' 535 is only a week old. My 650's mileage improved significantly over the first 2k mi, ie, the breakin period. In addition to reduced engine friction, I beleive the tranny s/w goes through a "learning" period which may increase efficiency of shift points with time.

Spyder
05-07-2007, 05:43 PM
If you're making more power....

SteVTEC, That was a knowledgeable and informative post, especially interesting to me since I ordered an ED 535 last week (delivery is 22 June).

Judging from your handle, you may be interested to know that I pruchased new, and still own, the first VTEC car made, a '91 NSX:angel:

nahugry
05-08-2007, 08:17 AM
you may be interested to know that I pruchased new, and still own, the first VTEC car made, a '91 NSX:angel:

Smart man..... and a man who can be respected for his wiseness...:thumbup:
I love the car

Spyder
05-08-2007, 08:45 AM
Smart man..... and a man who can be respected for his wiseness...:thumbup:
I love the car

Thanks. It has about 60k mi on it now, is in pristine condition, and I've done almost all the maintenance on it over the 16 yrs I've owned it.

flexstar
05-08-2007, 10:20 AM
If you're making more power, you'll be burning more fuel, regardless of engine size. All the elements are there on the 535i for it being reasonably more efficient than a 550i. It's lighter, the 3.0L I-6 has less friction, it still has a high compression ratio (thanks to direct injection) and with the turbos it'll have a higher average BMEP than the 4.8L V-8 when making the same amount of power which is also good for efficiency. And the turbos have special materials to allow them to handle extremely high exhaust gas temps which lets BMW run a leaner air-fuel mixture as opposed to a lot of other turbo engines that tend to run very rich (less efficient) with cooler EGTs in the name of turbo reliability and engine longevity.

What is BMEP? Other than that I get your point.

SteVTEC
05-08-2007, 02:09 PM
SteVTEC, That was a knowledgeable and informative post, especially interesting to me since I ordered an ED 535 last week (delivery is 22 June).

Judging from your handle, you may be interested to know that I pruchased new, and still own, the first VTEC car made, a '91 NSX:angel:SWEET! :thumbup:

Congrats on owning a classic and also a piece of history. I still love those cars, although technically the first VTEC cars were '89-ish Integras sold in Japan, with a B16A1. The NSX was the first car to get VTEC in the US a few years later in '91. ;) Back then the car was revolutionary, created a lot of hype, embarassed Detroit V8's with liters more displacement, and also won Honda legions of loyal fans. I think they've gotten lazy since then though, which is unfortunate. I thought Honda would have been the one sporting Valvetronic, but instead their $50k RL flagship has the same SOHC VTEC as a 1993 Civic. :tsk:

Anyways, that's for another discussion on another day. :)

SteVTEC
05-08-2007, 02:16 PM
What is BMEP? Other than that I get your point.BMEP = Brake Mean Effective Pressure

Spyder
05-08-2007, 08:20 PM
SWEET! :thumbup:

Congrats on owning a classic and also a piece of history. I still love those cars, although technically the first VTEC cars were '89-ish Integras sold in Japan, with a B16A1. The NSX was the first car to get VTEC in the US a few years later in '91. ;) Back then the car was revolutionary, created a lot of hype, embarassed Detroit V8's with liters more displacement, and also won Honda legions of loyal fans...

Thanks! I should have wrote the first VTEC car in the US...

It never fails to amaze me how much attention my 16 yr old car commands, and even though it's now far from state-of-the-art performance-wise, it still has great balance, and is a blast to drive fast, which, living in the Santa Monica mountains, I get to do every time I leave my garage:drive:

lawbuz
05-08-2007, 09:33 PM
Originally Posted by lawbuz
Just picked up my 2008 535i last week. I hit emply after about 315 miles. I don't know the tank capacity, so please compute gas mileage -- does not sound that great. I've driven on both highway and city.

Response:
16 gallons.
315(19.6 mpg) miles- that seems really low unless you were stuck in traffic most of the time.
What was you average speed?

Reply: It was a combination of highway and city rush hour driving, with me pushing it hard a few times (it was new and wanted to see what it had).

Question - Assuming I test mpg for the next couple of times I refill and it gives me a low mpg reading for city and highway driving (say, at less than 22mpg), what can I do to investigate a possible problem? Could pushing the car a little hard during the initial break-in period cause immediate adverse effect on mpg?

jacksonhunter31
05-09-2007, 06:55 PM
drove 1300 miles during ED, averaged around 22 mph, drove the car hard over mountains and averaged 100 plus mph on the highway...my guess would be that regular US driving with a 50/50 mix of highway and town will result in about 24-25 mph..

Bikie
05-10-2007, 11:12 AM
Picked up our 535i last week in Munich 635 milesso far split between 100+ on Autobahn and slow villiage and City traffic averaging 22mpg by trip computer.

kimbo1
05-11-2007, 12:17 PM
I would be skeptical of trip computer mileage computations. My 1998 E39 549, picked up on an ED, gave fabulous TC mileage results. However, in keeping a log and doing computation the old fashioned way (paper, pencil, calculator), I found the TC mileage to be ~25% optimistic. Once the car was redelivered in Seattle, I had it back to the dealer 2-3 times to reprogram the scale factors the TC uses. Finally got the TC to match reality within 1-2%. Trust, but verify!

Next month I will be doing another 5 Series ED, this time for a 535Xi. And I already have my fuel log book ready to go. BTW, there are a couple of PDA programs, such as CarCare, that can track mileage, too.