big_ipaq

Why then 0-100 km/h is better for the petrol versions?

In my opinion 50-75 mph acceleration figure, has absolutely nothing to to with performance, as it is perceived by almost anyone, falling for the trick, but it has to do with comfort because of engine elasticity...

BetterMakeWay

This is exactly true... In 4th the 525d would win! These figures are a standard way of 'comparing' models (petrol and diesel), as well as the 0-62mph (0-100km/h) benchmark - they were not formulated to give one an 'advantage' over the other... It's not saying that the 525d is faster from 50-75 under all conditions...
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And another truth is, it's more likely that you are in the fourth gear in 50mph than in the third gear. Then it will take you one extra second change gear and hit the pedal...
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Yes. I agree.
In fact the purpose of those figures is to show the flexibility of the engine (real life performance). Most of the time u will be unprepared and caught off guard to simply change it in a lower gear. For example a guy wants a bit of a race and goes by u, or u are being caught within some meters from the stop light on yellow or u have to overtake at the limit...or whatever, i can't think of all the scenarios. When a petrol has to downshift to get the juice out of the engine the diesel will simply take advantage of all the torque and accelerate. Now the time for downshifting means time is lost so that is why those numbers are given. Not just a marketing strategy, it's real life usability. Some people i heard bragged about the surge of the Audi s4 vs bmw m3 in test drives. And parts of that is true, the s4 has alot more torque that comes at lower rpm meaning u don't have to rev the freaking engine to kindom come everytime u want to move faster, and being in the m3 sometimes u even have to downshift 2 gears to find urself in the correct rpm range. LOL And that's about where the d-bate ended. Ohhh in fact the dbated ended after that, when audi lovers ivoked the winter usability. ))))

SKK

But isnt it true that the vast majority of 5 series sold are automatics (actually all 535d's are autos) so when you press the accelerator hard at 50mph both the petrol and diesel models will downshift ??

With an automatic box not many users are going to be cruising using steptronic mode fixed in fourth gear....

BetterMakeWay

The times with steptronic are taken without using kick down.

SKK

The times with steptronic are taken without using kick down.
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I know that but how many drivers will be using the steptronic fixed in fourth gear at 50mph ? The vast majority will not so the auto box will kick down a gear or two when the accelerator pedal is pressed hard....

A 530i will beat a 530d from standstill at the traffic lights (same with the 540i vs. the 535d) and before you ask - yeah its still good fun even at 34 years old Maybe I need to do some growing up

big_ipaq

Comparing x to y kmh acceleration times in a fixed gear is pointless. Gears ratios are not even the same if I recall correctly. The times, are there NOT for comparation but for understanding each engine along with its gearbox.

If someone does not believe this, try to race from 80 kmh to 120 kmh a 530d with a 530i and you'll see. Just don't try to fix one or another into a specific gear.

BigGrey

This is similar to the 2 vs 4 stroke motocross bikes. Until a few years ago, 4 stroke where considered useless and who saw it as the future was called mad. But now.... where are the 2 stroke engines? gone!

This because users want two things: durability and usability. And in those areas, i see no reason not to go to a diesel. Infact it is getting very hard to justify why not to go for a diesel.

The "don't have to shift down" is just a clear example.



BTW: i miss the sound of the 2 stroke engines and it's smell

BetterMakeWay

Seems good to me the last statement.
I for one hardly can wait to get or to challenge a 540i.

Although the 540i is faster from 0-100km/h by 0.3 seconds, the time is equal from 0-1000m (25.9sec). The 540i is manual but even so i do think the 535d can do with 540i. I dunno...i'll just have to wait and see.

Even so i do think that even with the 530i in the powerband and the 530d at it's torque peak and turbo spool rev range the diesel would win the race.

colejl

As ever over-simplified for the masses. Proper road-tests tend to list the individual performance stats for each gear for those who care...

big_ipaq

You mean E39??!? E60 only had 545i and now 550i.

I think 535d should be very close to 545i in performance, isn't it?