RE: Driven: BMW M550d xDrive

RE: Driven: BMW M550d xDrive

Author
Discussion

tommy vercetti

11,486 posts

162 months

Tuesday 28th February 2012
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Shame it's not coming to the UK, would have been great even if they made a few for the UK market. Sounds very exciting, 3 turbos lick

lap_time

339 posts

226 months

Wednesday 29th February 2012
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E38Ross said:
But then you're saying why make an m5 when a 520d is just as good on the motorway

I'm sure you've never gone above 70 rolleyes

8 forward gears is plenty and better than 7,so long as it's not shifting too often perceptibly. If it's not perceptible it does matter, as it offers better performance and economy.
That's the thing though - the article said the amount of gears WAS getting in the way of enjoyable progress. Fast gear changes, but just so many of them that it did interrupt the fun. Don't get me wrong: it's undoubtedly faster and more efficient, but (according to Harris anyway) somewhat annoying.

Orbin

216 posts

145 months

Wednesday 29th February 2012
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this car in touring format would be close to being the best all-round car you could buy. dear bmw, why oh why can't we have this in the uk?

E38Ross

34,948 posts

211 months

Wednesday 29th February 2012
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lap_time said:
E38Ross said:
But then you're saying why make an m5 when a 520d is just as good on the motorway

I'm sure you've never gone above 70 rolleyes

8 forward gears is plenty and better than 7,so long as it's not shifting too often perceptibly. If it's not perceptible it does matter, as it offers better performance and economy.
That's the thing though - the article said the amount of gears WAS getting in the way of enjoyable progress. Fast gear changes, but just so many of them that it did interrupt the fun. Don't get me wrong: it's undoubtedly faster and more efficient, but (according to Harris anyway) somewhat annoying.
first bit of criticism i've heard of the 8 speed box. ever.

it's actually no more forward gears than you'd use normally in a fun drive anyway, since 7th and 8th are both gears which will not be reached if going flat out (i.e. top speed usually met in 6th, 7th at most) so don't see the problem, especially if used in manual mode

Guvernator

13,109 posts

164 months

Wednesday 29th February 2012
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E38Ross said:
first bit of criticism i've heard of the 8 speed box. ever.

it's actually no more forward gears than you'd use normally in a fun drive anyway, since 7th and 8th are both gears which will not be reached if going flat out (i.e. top speed usually met in 6th, 7th at most) so don't see the problem, especially if used in manual mode
Yes but why do you need 8 gears? I understand on a bike where the motive power is your legs and how having more gears is a big help but this is a car with a very modern tri turbo engine. Surely one of the huge advantages of a modern turbo engine is the huge spread of torque they produce over a very broad rev range which makes a high number of gears totally irrelevant? To me it smacks of marketing one-upmanship. Over-complication for it's own sake and just more bits to go wrong, further down the line.

Pumpsmynads

267 posts

155 months

Wednesday 29th February 2012
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Is it the same (or closely related) to the 8 speed ZF unit in the Mercs and Jags?
I've test driven both and found them excellent though I see the point with regards to changing down. Coming from a 6 speed manual diesel where you just put your foot down and enjoy the uninterrupted acceleration until you reach whatever speed, I found myself pushing the autobox across into manual before putting foot down just so it wouldn't change down. Sort of defeats the object so I'm sure if I had one I'd stop doing that and get used to the downchanges and likely better acceleration.

E38Ross

34,948 posts

211 months

Wednesday 29th February 2012
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Guvernator said:
E38Ross said:
first bit of criticism i've heard of the 8 speed box. ever.

it's actually no more forward gears than you'd use normally in a fun drive anyway, since 7th and 8th are both gears which will not be reached if going flat out (i.e. top speed usually met in 6th, 7th at most) so don't see the problem, especially if used in manual mode
Yes but why do you need 8 gears? I understand on a bike where the motive power is your legs and how having more gears is a big help but this is a car with a very modern tri turbo engine. Surely one of the huge advantages of a modern turbo engine is the huge spread of torque they produce over a very broad rev range which makes a high number of gears totally irrelevant? To me it smacks of marketing one-upmanship. Over-complication for it's own sake and just more bits to go wrong, further down the line.
You're missing the main point. Economy and refinement. On the petrol cars 8th gives just 1500rpm at 75mph. And for acceleration 8 gears is better than 6 idf the ratios are closer together. Torque may be flat over a large rpm band but when doing higher rpm its making more power, having more gears could mean you can stay in the higher power band for longer, and a very tall top gear means better economy.

Wills2

22,669 posts

174 months

Wednesday 29th February 2012
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Pumpsmynads said:
Is it the same (or closely related) to the 8 speed ZF unit in the Mercs and Jags?
I believe all the F10/11 autos are the ZF 8 speed box,

The jury is out for me I find it quite frustrating that it still has the same issues as the 6 speed tiptronic in my Allroad and the 5 speed auto I had in the SL, in low speed up hill corners they always put themselves in the wrong gear and you have that silly pause whilst the computer works out whats going on, and drops a cog or two.

Also when approaching a roundabout off the throttle using light braking you see a gap release the brake and transfer to the throttle and again the box is lost in no man's land leaving you hanging halfway across the road.

Could just be me...

PascalBuyens

Original Poster:

2,868 posts

281 months

Wednesday 29th February 2012
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sleep envy said:
have you driven one yet?
No, and I don't intend to either...

StevieB

777 posts

147 months

Wednesday 29th February 2012
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Never mind the M550d, people wanting one of these should just buy the Alpina D5 that Sutcliffe tested in last weeks Autocar. he rated it over the M5 as a daily car, something ol' Chris Harris would never do! Also, Autocar averaged 39 MPG in the diesel and just 18 in the M5, so if Chris Harris thinks an M5 would ever do mid 20s MPG, he is kidding himself. All these new petrol turbos have totally false MPG claims. THe Audi S4 run by EVO only averaged 23 MPG against an advertised 29.7 over the year they had it.
Hardly any better than the V8 S5 they also ran...!!

vr6dom

8 posts

223 months

Friday 2nd March 2012
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Chicane-UK said:
The Article said:
The only clue you are driving something very special is in the rather clumsy, hi-fi augmented intake noise (in Sport Plus mode) that sometimes sounds like a Corrado VR6 that's dropped a cylinder.
So like a Golf V5? smile That is pretty much a VR6 with a cylinder lopped off!
Nah... he means when the coilpack goes... thanks Chris, just reminded me of when mine decided to whilst on Tower Bridge back in the day! That went down well biggrin

bakerstreet

4,755 posts

164 months

Friday 2nd March 2012
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AlpinaB5s said:
quote "Why a car with such immense core strength should need eight forward gears is anyone's guess."

Well, the biggest criticism of autoboxes in the past has been the fact they are often in the wrong gear.

Having more gears (in between the old gears) ensures a smoother and more efficent journey. I suspect that these new 8 speed ZF auto boxes are as close to 6 speed manuals with respect to efficiency.

Can't wait until the crank the forward gear count up to 11!
6 speed manual is only as efficent as the person driving it! People like BMW claim that the auto is better on fuel than the auto thanks to dual clutch technology.

I think ZF have launched an 9 speed box. Didn't know there was a 10sp out there .

pSyCoSiS

3,581 posts

204 months

Tuesday 6th March 2012
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And would a heavily-remapped 535d be far off in terms of performance?

BMW - stick to what you do best - making a decent chassis and keeping it rear wheel drive!

sleep envy

62,260 posts

248 months

Wednesday 7th March 2012
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PascalBuyens said:
sleep envy said:
have you driven one yet?
No, and I don't intend to either...
rolleyes