Hormazd

Any comparisons of a brand new 550i and a 545i should be made after the 545 has just had its oil changed. I think it makes a world of difference. See this post.

znod

Thanks much. For the 750i, the crudest of calculations gives: 330/360 (6) = 5.5. BMW's claim is 5.8. So, what we see is pretty much par for the course. Given the same sorts of about .3 discrepancy between BMW and the 545i, then the 550i will be exactly 5.5 - .3 = 5.2 to 60. I guess I won't do any regressions after all for 0 -60. I'll get back to you on the 1/4.
[/quote]Here's something interesting we haven't though of before. Zero to 60's for the X5 4.8 and X5 4.4 are 5.9 and 6.8--a difference of .9 in favor of the 4.8. And, the 4.8 has the higher rear end and weighs a little more. Hummm! Well, OK, then, the 550i should go to 60 in 5.2 - .9 = 4.3. So, that won't happen because that's essentially as fast as the M5 in the current test. So, I wonder what gives with the X5 figures.












The X5 weighs a whole lot more...





[/quote]





Than the 545i...
[/quote]
The comparison I made was between two X5's--the 4.4 and the 4.8.

Boy, you may be right, but I've never heard of a car needing a performance enhancing oil change every 6K miles. I think I'll get mine changed though at 6K if I develop sluggishness.

530iii

Ok vnod, must've been my thick skull.


I wonder if the upcoming all new X5 8 cyl models will have the corporate 4.8 V8 as standard...

EBMCS03

Of course!

znod

I am not sure why they would. The 4.4 is a good performer, and having 2 or more engines in a line allows differential pricing and potentially more buyers--like with the 5-Series cars.

EBMCS03

I am not sure why they would. The 4.4 is a good performer, and having 2 or more engines in a line allows differential pricing and potentially more buyers--like with the 5-Series cars.
[/quote]

Cuz BMW wont want to produce so many different engines... just like how they dropped the 545 engine for the 550 and the old 3.0L engine for the new R6 engine... They're even going to use the R6 engine in the Z4 now. So I'm sure they'll drop the old 4.4L X5 engine for the new 4.8L

Wait... or are you guys talking about the 4.8is engine? If thats the engine you're talking about then No.. they'll still keep that for the 4.8is and have the 550 engine for the regular production X5. Thats what I think...

znod

Cuz BMW wont want to produce so many different engines... just like how they dropped the 545 engine for the 550 and the old 3.0L engine for the new R6 engine... They're even going to use the R6 engine in the Z4 now. So I'm sure they'll drop the old 4.4L X5 engine for the new 4.8L

Wait... or are you guys talking about the 4.8is engine? If thats the engine you're talking about then No.. they'll still keep that for the 4.8is and have the 550 engine for the regular production X5. Thats what I think...
[/quote]
I think you have the discussion right. And, what you say makes sense. But, still, offering a variety of engines, in a given series, allows sales to different market segments. So, they might want to have a 4.4 and a 4.8, for example, available in the X5 just as they have several engines in the 5-Series cars and the 7-Series cars. Differentiating in a series satisfies a different goal than does using the same engine across various models in different series.

Centurion

This thread took a turn off course.
Still, I learned a lot about motors. I'll admit, I was somewhat shocked to see 0.1sec quicker times for the 750i vs. 545i. Bigger car, more space, and very similar straight line acceleration. Hmmmm.....(looks at checkbook).

Back on topic, I think the differences are going to be VERY subtle between the 545 and 550 in terms of "feedback" one gets from driving each car. Now, where did I put that 7-series catalog?

znod

Are are the stats from Car and Driver Mag (C/D):

545i
Transmission: 6-speed manual
Wheelbase: 113.7 in
Length/width/height: 190.6/72.7/58.0 in
Curb weight: 4000 lb
Zero to 60 mph: 5.5 sec
Zero to 100 mph: 13.2 sec
Zero to 130 mph: 23.5 sec
Street start, 5-60 mph: 6.0 sec
Standing 1/4-mile: 14.1 sec @ 103 mph
Top speed (governor limited): 150 mph
Braking, 70-0 mph: 156 ft
EPA fuel economy, city driving: 17 mpg
C/D-observed fuel economy: 16 mpg

The 750i
Transmission: 6-speed automatic with
manumatic shifting
Wheelbase: 117.7 in
Length/width/height: 198.4/74.9/58.7 in
Curb weight: 4505 lb
Zero to 60 mph: 5.4 sec
Zero to 100 mph: 13.1 sec
Zero to 130 mph: 23.6 sec
Street start, 5-60 mph: 5.9 sec
Standing 1/4-mile: 13.9 sec @ 103 mph
Top speed (governor limited): 148 mph
Braking, 70-0 mph: 164 ft
Roadholding, 300-ft-dia skidpad: 0.88 g
EPA fuel economy, city driving: 17 mpg
C/D-observed fuel economy: 15 mpg

Based on the C/D test, using simple algebra, and given that the 550i adds 100 lbs, solve for X:

550i
Curb weight: 4100 lb
Zero to 60 mph: 4.91 sec
Zero to 100 mph: 11.9 sec
Zero to 130 mph: 21.5 sec
Street start, 5-60 mph: 5.4 sec
Standing 1/4-mile: 12.65 sec @ 103 mph
Top speed (governor limited): 150 mph
Braking, 70-0 mph: ***

Traveling at 100 mph, one would travel 145 feet per second. Hope I'm not misleading anyone. 5280 ft/mile.
[/quote]
FYI, here is some Dragtimes data for the 750i.

0-60: 5.4
1/4 Mile ET: 13.910
1/4 Mile MPH: 103.120

But, they are so consistent with the above data that I suspect they reflect the same test.

Saudi_545i

Thanks much. For the 750i, the crudest of calculations gives: 330/360 (6) = 5.5. BMW's claim is 5.8. So, what we see is pretty much par for the course. Given the same sorts of about .3 discrepancy between BMW and the 545i, then the 550i will be exactly 5.5 - .3 = 5.2 to 60. I guess I won't do any regressions after all for 0 -60. I'll get back to you on the 1/4.
[/quote]Here's something interesting we haven't though of before. Zero to 60's for the X5 4.8 and X5 4.4 are 5.9 and 6.8--a difference of .9 in favor of the 4.8. And, the 4.8 has the higher rear end and weighs a little more. Hummm! Well, OK, then, the 550i should go to 60 in 5.2 - .9 = 4.3. So, that won't happen because that's essentially as fast as the M5 in the current test. So, I wonder what gives with the X5 figures.
[/quote]


isn't the 4.4 that was in the X5 the old 4.4 though?? i maybe wrong.. but i'm sure it's the case
[/quote]
That's a good point. I am not sure. I looked, and it is the old one. I should have know since we have a 4.4 X5. So, the HP difference is 50. Still, given the .9 sec difference, I am very glad the 545i has the new 4.4. In other words, .9 still seems like a large difference even given the old 4.4.
[/quote]
I think the easiest way to find out 550 VS. 545 0 to 60 is to compare it to 750 vs. 745. Anyways, I find it hard to believe that a 750 will out preform a 545 given the fact that 545 HP to weight ratio is greater than the 750s. Not to mention that added weight makes the 750 harder to launch.