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The development of a 6 speed manual version of the new M5 for the US market made me think about speed differences.

Surely the shorter gearing of the manual will mean that it's top speed is significantly less than an equivalent SMG equipped car since the SMG is a 7 speed gearbox. This assumes, of course, that the limiter is removed.

Additionally, using launch control I experienced insane shift speeds (much quicker than I could manage with a manual). This automated shifting combined with closer spaced gearing should mean a faster 0-60 time for the SMG as well.

Any thoughts on this?
 

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Ashok Arora said:
The development of a 6 speed manual version of the new M5 for the US market made me think about speed differences.

Surely the shorter gearing of the manual will mean that it's top speed is significantly less than an equivalent SMG equipped car since the SMG is a 7 speed gearbox. This assumes, of course, that the limiter is removed.

Additionally, using launch control I experienced insane shift speeds (much quicker than I could manage with a manual). This automated shifting combined with closer spaced gearing should mean a faster 0-60 time for the SMG as well.

Any thoughts on this?
My guess -- and that's all it is -- is that the SMG will be faster by just a few tenths than the six-speed, even when not using launch control, as long as the higher S settings are used. First, the car was designed to work SMG from the outset. It is likely that this combination will work somewhat better than an older manual transmission. Second, by all accounts, the SMG can shift much more quickly than anyone can shift a manual. The only circumstance in which the SMG times may suffer is if its shorter gearing would require an extra shift. Still, given the speed with which those shifts are accomplished, I suspect that the SMG still will have an edge.
 

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I beleive in higher speeds the manual version will be noticably slower. But this is impossible to say when yuo dont know the gearing of the manual 6-speed car, but it abvious it wont have as close ratios as the 7-speed.
 

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Gustav,

At what RPM does LC launch? Do you believe that LC's RPM level and the clutch let-out were fairly optimal and that it has enough engine momentum to get it through the weak part of the torque curve in first? Did you notice anything it did that an expert could do better with a manual?

The answers to these questions will pretty much answer the question posed in the thread subject, and least for short sprints like 0-100k. In the case of SMG II and the E46 M3, an expert could do better than LC as shown by numerous magazine reviews. However, I am led to believe that SMG III is not only far better generally, but LC is also greatly improved.

Tom
 

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Around 4000 rpms. It felt like most of the time the launch felt optimal, not too much of wheelspin, a little rev-drop and then hard BANG shiftings at each gear. I didnt do this too much but with our improvised measuring equipments the times seemed very good.

An expert should be able to repicate the start, yes, but the shifts from esp. 1-2 shifts would be difficult to do on a continous basis. Although SMGIII won't allow you to do it on continous basis either...

But also flooring it with some moderation in S6 mode would be quite fast as well.

I also beleive it is more difficult to launch the M5 than M3, so the LC helps more here. I have also seen the M3 CSL launches numerous times and they did not seem to be optimal. However I could learn more about that.
 

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6 vs 7... of course 1 gear has to go.
if the 7th gear is gone (OD), may be just higher rpm at cruising.
top speed is limited anyways.
 

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yes, what gustav said... in the real world the 6-speed will be slower everywhere (slower human input, and in theory it will be slower once you hit whatever gear will be after the 1:1 in the manual (6th?) ...

but i will still take one in a heartbeat, because as i said- the m5 is about enjoyment and personal satisfaction. if i wanted race-track gearbox i would not be in an m5 to begin with :)

besides, the main m-division guy (dont remember which one) once boasted - "the m car is all about high-revving engine, balance and manual transmission"- or something similar...

alex
few cars
 

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Well, I don't see why the manual can't have 7 speeds. Gates would be a little close, but not a real show stopper. Of course, it would require BMW to engineer a totally new transmission.

Will it be slower? Well, that depends on alot. Specifically, which measurements you are interested in. It could be quicker from say 0 to 60 or 100.. The reason I say this, if the gearing is setup correctly, it might be able to delay the 1st to 2nd shift until after 60.. or, possibly starting in 2nd gear (assuming you are willing to abuse the clutch a bit). At higher speeds, a 6 speed would probably be slower, but a 7 speed would be pretty close. Around a track, I am sure the SMG would be faster.

I am going to give SMG3 a chance.. but already on the list for the manual, for the reasons Alex mentions.
 

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I think that the manual cars are always faster than the SMG? It may be due to the way SMG system operates.... At least that has been my experience... I do not have any data to suport this but it feels that way? :rolleyes:
 

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M5_2010 said:
I think that the manual cars are always faster than the SMG? It may be due to the way SMG system operates.... At least that has been my experience... I do not have any data to suport this but it feels that way? :rolleyes:
So far, the data from the carmag testing on BMW SMG's has shown manuals to be faster. The only reason for this, using professional drivers, is that they have been able to launch the car better with a manual.

If the launch program for SMG III is as good as a professional driver, then the SMG will be faster. If it's not quite as good, then SMG will be equal or slower. I'll guarantee that SMG will be quicker for the 'street driver' 99% of the time, just because of the difficulty of getting a really good launch. SMG will also be quicker than any of us in terms of shift times. The bottom line is that once rolling, SMG will be quicker.

Until the manual M5 comes out, we won't know about how good SMG is vs the manual from a launch.
 

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M5_2010 said:
At least that has been my experience... I do not have any data to suport this but it feels that way? :rolleyes:
But you are basing that on the series cars' SMG, not the M version, correct? The series cars feel VERY slow with their SMG, at least to me.

The M3 could be much faster with better launch control.
 

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vndkshn said:
But you are basing that on the series cars' SMG, not the M version, correct? The series cars feel VERY slow with their SMG, at least to me.

The M3 could be much faster with better launch control.
Series cars use a 3rd party gearbox and its nothing like the M3's SMG.

One thing that concerns me is there is no offical word on LC usage and warranty claims that I have heard of, has anyone got this information?

I know there was a gray area with SMGII and LC, something along the lines of 6-10 launches was acceptable, but I think it was down to the relationship with the dealer as to what was actually acceptable for warranty to still cover the clutch.

Also does anyone know why the US SMGII LC was restricted to about half the revs of the UK version for launch? And if this same reason would be carried over to the new SMGIII cars??? As that would trully dent any LC 0-XXX bragging rights.
 

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Yesterday I drove a Golf GTI with DSG on the track.
DSG = Double clutch.

I just can't see how anybody could change gears faster than that!

It's done in milliseconds, and it works perfectly!

The GTI was an excellent car btw, almost no fwd-feeling at all. :wroom:
 

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SUPRA said:
Yesterday I drove a Golf GTI with DSG on the track.
DSG = Double clutch.

I just can't see how anybody could change gears faster than that!
The manual will be slower.
 

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HomerUK said:
Series cars use a 3rd party gearbox and its nothing like the M3's SMG.
I know, that was my point. He has made multiple references in the past to SMG, based on his experience with his 545i SMG.
 

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My prediction is that any manual M5 will be about 0.5 seconds slower from 0-60 mph, and the difference will only become greater as speeds increase. That's with just S5 or S6 mode; LC will be even quicker in the 0-60 mph range.
Bish

PS Perhaps we should start a betting pool?
 

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I think the series BMW SMG gearbox comes a different source than the M gear box. They are two different animals.

I think for your typical driver, SMG3 will be faster- and more consistent.

AJ has it right though- who cares about absolute speed. M cars have always been about balance. I am very curious to test out SMG3 for myself. I think if you go for the stick shift, its not for speed. Btw- one of the best parts of the Z8 DE was being driven around the track by one of BMWs drivers with them driving what felt like 9-10/10ths and feeling the car literally being at its limit and the up shifts were nearly brutal, like how SMG2 felt when you had it in full attack mode and what it seems like SMG3 does. What I am also curious to see is the difference between SMG3 and the stick shift with this particular car.
 

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AJ said:
but i will still take one in a heartbeat, because as i said- the m5 is about enjoyment and personal satisfaction. if i wanted race-track gearbox i would not be in an m5 to begin with :)
Main reason for SMG for me is the fact that I'm probably not going to be driving it just for pleasurable reasons.

It's always great to stick the car in automatic, when stuck in heavy traffic, or when on the phone, etc etc. Nothing worse than crawling in heavy traffic between two or three gears and having to change them every couple of seconds. Just so sometimes, you don't have to worry about changing the gears, it's all done for you.
 

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vndkshn said:
No way the the zero to 60 will be a half second slower with a manual....
Right, at most a tenth slower. With a professional driver, and multiple tries, it will probably be a tenth quicker. The idea is that a pro driver with multiple attempts could feather the clutch to achieve a 'perfect' launch. My understanding is that the SMG launch control will modulate the throttle, not clutch engagement.
 
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