wales34part

Not directly as a result of this hugely developing debate but merely as a result of opportunity i have this week had opportunity to drive a 35k miles e61 535d, state of tune ie remap unknown and a 545i e61 4k miles both autos both 18" run flats with non staggered wheels.

I'll point out here that i am an avid fan of diesel hence my current e61 520d m sport.

I have no way of gaugeing whether each example was loose, tight, tired in the case of the 535d but i can quite catagorically state that the 545i was in a different league to the 535d in term of putting a grin on my face. Power pick up was instant and much stronger than the 535d and as for the noise i actually thougt the 535d at full throttle was less refined than my humble 520d under similar full throttle application. By contrast the 545i was as smooth as silk
I dont really care which is faster or more economical as i have no need personally for either engine option (i'd sooner put the saved money to a "proper" sports car), but what counted for me was grin factor and the 545i has it all the way over the 535d

Needless to say returning to my 4 pot diesel was a humbling experience

znod

znod

I have inserted my replies in orange below. I am having an inordinately hard time getting the quotes to work properly. Sorry.

I keep saying over and over that test reports will not provide definitive anwers. However, I also refer continuously to the idea that preponderance of evidence often can lead to proper conclusions when data are messy. I have done no picking and chosing. I have based my conclusions on all empirical data I am aware of. I have, in fact, gone out of my way to give the 535d every reasonable benefit of the doubt. I have even suggested averaging the tests or throwing out the two bogus-looking tests. I think that your accusation is ill founded and, honestly, quite surprising and disappointing--given the mutual respect I thought we had and the lengths I have gone to to demonstrate objectivity.

To this point, you and the other 535d fans have misconstured or misuderstood virtually everything I have said. Not including you, I can only conclude that the misconstruals come from a strong need to deny the obvious--assuming the data I have posted are understood. I am somewhat aghast at the lack of understanding of what the data I have posted mean and imply. But, denial of obvious conclusions is a common reaction when data are not studied carefully or are not understood--e.g., the Earth really is flat despite the empirical data to the contray.

You say essentially that if I have to justify my conclusion using magazine data, then there can't be a massive straight-line performance difference. Your conclusion does not follow from your premise. Regardless, BMW claimed 0 to 60 of 5.8 for the Steptronic 545i--which is very close to what 2 of the US mags got for this value. BMW UK makes these claims for the 535d--"535d SE * ?37,790 Diesel (32%) 2993cc Yes 35.3 mpg 6.5 [0 to 62]." Zero to 62 in 6.5 (i.e., the German mags got 6.5 and 7.1 for this value) seconds translates reasonably into about 6.2 seconds for 0 to 60 at best. A .4 difference (6.2 - 5.8) for zero to sixty translate into many car lenghts of difference at, for example, 100 MPH. To get an estimate of the car lengths of difference, assume conservatively that the .4 difference does not increase by 100 MPH (even though it very likely would increase). Then, noting that a car goes about 147' per second at 100 MPH, the number of car lengths of difference implied is 7.33 assuming that the cars are 20 ft long. That's a lot of car lenghts even given conservative calculations. I would call this number of lengths "huge" when it comes to straight-line performance.

I don't think your analysis of the sequence of my data posts is accurate. I posted all the magazine data I was aware of as soon as it seemed to become pertinent. Then, I updated my analysis as new magazine data came to my attention. I did not seek to do any sort of nefarious reporting. Again, I am very disappointed in your apparent conclusions about how I function. As I have said many times, I am very aware of all of the noncomparabilities. I also am aware that preponderance of evidence (e.g., from averaging, tossing out outliers, and eyeballing) can give good conclusions despite noncomparabilities in specfic tests.

I have indicated no preference for the test data except to point out one German magazine has produced one report on the 535d that seems bogus and that one German magazine has produced one report on the 545i that seems bogus. I did not search out anything selectively. I subscribe to the 3 US mags. I thought I did pretty well to provide 535d data to the original poster since I don't speak German. The test I reported on was posted on the BMW Germany website so I thought, at the time, that it would be a reasonable report. Now, I think it may understate the performance of the 535d. I invite the 535d guys to find full reports that will contrdict the 535d reports we now have. I also invite you to find full reports that contradict what the US magazines report for the 545i.

Please understand that I don't care which car is faster. I have no vested interested in which is faster. I am simply trying to provide the best empirical data we have on the issue and to try to draw what seems to be the more logical conclusion. Why would I care which car is faster? There are many cars faster than the 545i, and there are many slower.

Yes there are differences--which also is a good reason that a few drag races between a few cars of different models will not necessarily settle things definitively. Potentially, onne needs many such tests and cars to settle things definitively. However, even a single test would add a data point for use in assessint preponderance of evidence. Such noncomparabilities also may affect our ability to rely on specific test data. I have acknowledged that test data are not necessarily definitive. But, I also contend that preponderance of evidence often can lead to propers conclusions.

I am not trying to prove anything. I am simply pointing out what the preponderance of evidence implies. The fraction you refer to is quite large. Thus, preponderance of evidence implies, for example, that the 545i would be many lenghts ahead at 100 MPH.

As indicated several times, I talking only about straight-line performance. Regardless, what is your evidence for what you say?

As indicated above, I also don't care. The type of statements your refer to are ill founded. Personally, I have presented only the best empirical evidence I have been able to muster and have no vested interest in which car is faster. I simply am trying to provide empirical data that provide a reasonable basis for a conclusion. I have no bias against the 535d or diesels in general. I have made this point several times above. I am not emotionally involved in the issue. And, I will continue to base my conclusions on preponderance of empirical data, including testimonials, and not on emotion and bias. Note that one of our UK mates and 700700 have provided seat of the pants evidence above. I value such data points provide that I think the sources are unbiased. I believe that the two seat of the pants reports above are unbiased.

BetterMakeWay

Aaaaaand full stop.

needforspeed

znod - thanks for taking the time to respond and explain. I wasn't trying to offend and apologise if I did.

The reason I was struggling to understand your position was that the german car mag stats that you posted indicated a mere 0.2 sec difference from 0-100mph. These numbers suggested to me that the performance was 'close' at least in some tests.

I've done a little more research and found some other evidence to back up your thinking which might be of interest.

This site has loads of test data (not sure how it was gathered) and in terms of the 535d / 545i the numbers reflect what you have been saying.

http://www.modcar.org/pages/BMW

I've pulled off the data for the 535d with and without DMS and the 545i



looking at the 1/4 mile figures this shows 14.9 for the 535d and 13.49 for the 545i (this is the 1.5 sec difference that I said in previous posts I expected to see!)

In terms of this being close or not I did a little sum:

535d takes 1.41 secs longer to reach 1/4 mile than the 545i.

Assuming these last 4 secs are at terminal speed (bad assumption probably but helpful in understanding what distance might be covered ), during this time the car would cover 0.037miles or approx 60m. So the 545i would win by more than 12 car lengths!

e46 M3 CSL - would beat the 535d by 96m
E46 M3 would beat the 535d by 71m

DMS'd 535d is still behind the 545i - but only by a car length.

This helps me get over my sticking point - I already agreed with you that the 545i would win in a drag race.

These figures back up your position and reinforce what I thought should be the case - that the deisel would be a second or so behind at 100mph, which is reasonably significant.

I still think that this might change on a race all the way to 155mph and also, depending on the track, the 535d could trouble the 545i on a circuit.

In terms of the 'seat of the pants' perceptions - I'm not convinced that anyone is so attuned to performance that they would be able to discern a real difference in performance without measurement. I think it's perfectly likely that the 545i feels faster because it is more free revving and involving.

I'd be interested in your view on the stats on the posted site.

Peace

535D Sport

Here you go again attacking members of this forum who are only replying with their opinions liked or not... .Can you not reply to a topic without calling people names ?. By the way do you know what pleb means, you could probably apply it to 99% of the members on the forum, look it up. .One other thing you advise someone to do something not advice, just for future reference you cretin..look that one up...

pennetta

There are much greater frictional and hydraulic losses with a Steptronic verses a SMG. The SMG has a solid mechanical drive just like a regulat stick shift car. So if two cars are putting out the same crank hp/torque, the rear wheel hp/torque will be less on the Step car which will result in a slower acceleration time.

znod

I did't really think that you are the offending type. But, my hackles were starting to elevate a tad. Thank you for the very thoughtful reply.

And, yes, your additional data points support what I have been saying very strongly. In this regard, they add hugely to the preponderance of evidence. Thank you for finding the data. I will be adding it to post #1 of this thread.

I agree with your measurement thoughts. And, incidentally, the average time for the 545i beats the US mag times by .16 to .26 secs. Of more interest to me is that the 545i results shown in your data (13.54 avg @ 105.15 avg) are reasonable consistent with even my average values for my best 5 passes--13.467 @ 104.866. The averages from your data are almost spot on in relation to my long-run 1/4 ET after updating to 20.01.00 (40 tests, and ugh--20.01.00 slowed my car down) of 13.559 @ 104.159 (i.e., 13.54 - 13.559 is only -.019 secs.) How's that for confirmation of my meter results? Of course, we know grogan545's meter results are quite accurate since he calibrated his meter on a drag strip. I am glad particularly that I got through to you on what I have been talking about. I have felt like I have been . Getting through is the real reason I wouldn't let loose of the tiger's tail (see above).

znod

Check the evidence. It is all over the place--especially here.

znod

Please note that one accepts an apology--not excepts it. I think we should be tolerant of typos and putting the wrong word in place when hurriedly typing replys. I think 700700 was a tad annoyed about the way your were replying to me in replying to you.