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I was fully decided on the 6 speed MT becasue of a) my dislike for the SMG due to the clicking and clunking noises in my last M6, b) strange shifting patterns in automatic mode, and c) a just too 'electronic' feel of the car.

However, I have been research on the forum and now I am competely thrown off by reading about the nanny intervention features, and possibly a somewhat weak clutch that needs to be babied (and hence the restrictions). Plus, the acceleration won't be comparable to SMG, I take it that you lose about 0.2-0.4 sec to 60mph.

Granted, I will not be tracking my car, neither will I be doing donuts on a regular basis. Mostly daily dirving to the office and the occasinal highway assault, but need four door car this time. Anybody think I could be happy with the manual M5?
 

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I guess you have to not mind that DSC cannot be fully turned off. The best you get is MDM. Here's a related thread on that.
 

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I currently drive 06 E60 SMG, love the car, 13000 + miles, absolutely no problems. It's a daily driver. Had several E39 M5's never had a clutch problem or any problems other than front tire wear and a coil pack problem ONE time.

I ordered an 07 E60 6 speed manual identical to my 06 which is currently released to carrier meaning it's in the twilight zone between Newark and my Dealer. I'll probably take delivery next week.

In response to your post, the clutch is new. LUK designed a special 2 disc self adjusting unit just for this car considering BHP and torque requirements.

The diff in performance off the line, the DSC nanny stuff is much ado about nothing for someone who loves to drive a car.....I have yet to get loose and slide into my office parking lot. I spend most of my time trying to get around people who park in the passing lane on the interstate.
 

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I drove a 6 speed

I have a 06 SMG and had intended to sell it for a six speed box. I wanted no part of the SMG transmission when it first came out - I planned on getting rid of it. However, after driving the 6 speed - I will stick with SMG. The car felt antiquated to me and i clearly could not shift as fast, etc.

To each his own - but I will stick with transmission the car was designed for - I think it suits it better.
 

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Don't do it unless

I really do miss old-school heel-n-toe but SMG does it better. The main concern that I would have is the performance difference between 7 speed and 6 speed (disregarding who or what actually does the shifting).

One of the main reasons why the M6 is bloody fast is we have 7 short little gears that maximizes the torque.

With a 6 speed, you may be off the powerband / torque curve versus the 7 speed. I would love the see acceleration beyond 100 mph....this would be an excellent data point to see if the 6 speed hurts performance.
 

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This would be a good sim exercise. Paging Chuck!

Dave
 

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I've had my 07 6-speed for about a month. I previsouly had a e-39. I absoutley love the car. I would not hesitate to go with the 6 speed. I haven't tested the 0-60 times but the car is MUCH faster than my previous e-39. Lots of great features. I love the hill assist. It holds the car for a second so you don't have to worry about holding the clutch. I had my 1,200 mile service this past week and I got after it pretty good and the tranny nanny is a non factor.
If you like manual shift the car is PERFECT.
 

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Taipan said:
or maybe the 6 gears are equal in gearing and the 7th gear which takes you unlimited to 330kmh does not exist
BMWCCA reports the following gearing for the 6 speed and 7 speed gearboxes:

Sequential Manual Gearbox (SMG) SMG III 247
Ratios:
1st 3.99:1
2nd 2.65:1
3rd 1.81:1
4th 1.39:1
5th 1.16:1
6th 1.00:1
7th 0.83:1
Reverse 3.99:1

Manual transmission ZF Type G, 6-speed
Ratios:
1st 4.06:1
2nd 2.40:1
3rd 1.58:1
4th 1.19:1
5th 1.00:1
6th 0.87:1
Reverse 3.68:1
Final drive ratio 3.62:1

According to this, 6th and 7th are nearly the same ratio (predictable - I don't think BMW would want to create a situation where in top gear milage would be dramatically worse with the 6 speed forcing a higher gas guzzler tax). First in the 6 speed is slightly lower than in the 7 speed - probably to save a bit on the clutch and make it possible to get the car moving with less slippage. The other ratios have predicatably larger jumps between gears - so the 7 speed should be able to keep the engine in the power band better that the 6 speed.

Interesting to note that 5th on the manual is the same as 6th on the SMG - so the extra gear of the SMG has more bearing on what happens at lower speeds than at the very top end of the car's performance envelope.
 

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Using the gear ratios provided we can calculate the speeds in each gear...

SMG

1st 5,5 mph/1000rpm
2nd 8,3 mph/1000rpm
3rd 12,2 mph/1000rpm
4th 15,9 mph/1000rpm
5th 19,0 mph/1000rpm
6th 22,1 mph/1000rpm
7th 26,6 mph/1000rpm

This means that at 8250 rpm the maximum theoretical speeds in each gear are:
1st 46mph
2nd 69mph
3rd 101mph
4th 131mph
5th 157mph
6th 182mph
7th 219mph


Manual

1st 5,4 mph/1000rpm
2nd 9,2 mph/1000rpm
3rd 14,0 mph/1000rpm
4th 18,5 mph/1000rpm
5th 22,1 mph/1000rpm
6th 25,4 mph/1000rpm

This means that at 8250 rpm the maximum theoretical speeds in each gear are:
1st 45mph
2nd 76mph
3rd 115mph
4th 153mph
5th 182mph
6th 209mph

It shows clearly that 1st and the top 3 gears are almost the same and that the missing gear has been achieved by lengthening 2nd gear a bit and combining 3rd and 4th. This compromises on acceleration from 70-130mph. Thinking about it that is a bit odd if this a US-market only car because you'd expect the performance in those gears to be much more important than the performance in the top 3 gears. If it was my choice I would have left the first 3 gears pretty much the same, left top gear the same (fuel economy) and combined 4/5/6 into 2 gears.

Another thing is that the theoretical top speed in top gear in the manual car has been brought way down to almost the practical top speed. That should mean the manual version will be close to hitting the rev limiter at top speed as opposed to being friction-limited like the SMG version. It should also mean that the manual could be quite a bit faster in topgear...so at 180+mph. There is no logical reason for this seeing as the previous gear is identical for both the SMG and manual version.
 

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Good analysis. I asked Chuck (CSBM5) if he might do some acceleration simulations with his very cool program. I don't know how the tranny nanny will effect the accuracy of the calculations, since the program comprehends expected wheel spin in the modeling. Should be interesting.

Dave
 

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Another thing that becomes obvious is of interest to dragstrip junkies. The 1/4 mile times of the SMG car have been at speeds in the 110-115mph bracket. Top speed in third gear in the manual car is 115mph. So the quarter mile in a stock manual car will require 2 shifts - with any significant engine tuning it will require 3 shifts.
 

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wilsodh said:
Good analysis. I asked Chuck (CSBM5) if he might do some acceleration simulations with his very cool program. I don't know how the tranny nanny will effect the accuracy of the calculations, since the program comprehends expected wheel spin in the modeling. Should be interesting.

Dave
I ran the model with the data for the 6-spd gear ratios and rear-end. However, it exhibits a couple of things I have to mention since they don't model the real world situation. Cartest has no knowledge of traction control, so it assumes it can use the best launch rpm and spin the tires as needed off the line. In addition, on the 1-2 upshift, it shows some decent wheelspin (similar to the SMGIII runs, etc). Both of these, I believe, will not be allowed by DSC even in MDM mode in the 6MT E60 M5, so clearly these acceleration times below are not going to be achievable by the 6MT car. How much slower it is will have to wait until we get real car test data in addition to owners commenting on how the car behaves with a hard launch.

The simulation data below assumes no DSC intervention, so please do not assume these are real world achievable numbers of the 6MT car. In addition, the 6MT data assumes a highly experienced driver is shifting the car perfectly at the upshift rpm point and extremely quickly.

Cartest Simulation for SMGIII E60 M5:
0-60ft time 2.12 sec
0-60 mph 4.22 sec
0-100mph 9.47 sec
0-120mph 13.13
0-140mph 18.40
0-160mph 26.35 sec
0-180mph 42.70 sec
1/4 mile: [email protected]

Cartest Simulation for 6MT E60 M5:
0-60ft time 2.10 sec
0-60 mph 4.40 sec
0-100mph 9.67 sec
0-120mph 13.78
0-140mph 18.85
0-160mph 27.02 sec
0-180mph 43.20 sec
1/4 mile: [email protected]

As an aside, Cartest caluculates that the best performance rpm shift points for the 6MT are as follows: 8250, 8250, 8250, 7970, 7810.

Chuck
 

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True, didnt think of the MDM issue.

CSBM5 said:
The simulation data below assumes no DSC intervention, so please do not assume these are real world achievable numbers of the 6MT car. In addition, the 6MT data assumes a highly experienced driver is shifting the car perfectly at the upshift rpm point and extremely quickly.

Chuck
 

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CSBM5 said:
I ran the model with the data for the 6-spd gear ratios ..
Another interesting analysis Chuck! The hypothetical 'no nanny' comparo is actually nice because it helps clarify the differences in results as being due to other factors. What do you see as the key difference(s) here? Shift speed? Gearing? Also, what gears were the cars in in the traps?

Dave
 

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the question is this: what is the "experience" of driving to YOU. Is it just gas and steering wheel? If so, SMG for you. Or is it real communication with and control of the car? gas/clutch/gears/steering wheel. If so 6 sp.

Me? 6sp all the way; it is a sports car with 4 doors, not a family car with a V10.
 

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The February C&D tested the manual M5:

0-60 -- 4.7 sec
0-100 -- 10.3 sec
0-150 -- 23.4 sec
1/4 mi -- 13.0 @ 114 mph

So, the manual takes almost 1/2 second more to 60, a half second and a couple mph in the 1/4-mile, a full second to 100, and a whopping three seconds to 150.

But look . . . you have to decide how much this matters to you. If what you really value above all else is shifting a traditional manual, and don't plan on tracking the car, the manual may be the better choice for you. If, on the other hand, maximizing performance is your priority, it is undeniable that the manual leaves something significant on the table.
 

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Go with the stick, you sound like you won't mind your hands being tied, driving the stick....
 
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