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View Poll Results: What Transmission would you want in your M6?
1.) Manual 75 46.30%
2.) SMG 61 37.65%
3.) Automatic 24 14.81%
4.) CVT (Hybrid Auto) 2 1.23%
Voters: 162. You may not vote on this poll

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  #76  
Old 06-02-2005, 12:02 PM
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The HACK The HACK is offline
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Quote:
Originally Posted by Stuka
To be a sport machine, a car will have to have brakes that actually work.

M6 has ****e for brakes. GImme a break, for the $$ that they are charging, why can't they put a monobloque 6 pot Brembo's up front, and 4 pot Brembo's in the back?
Man I hope you posted this BEFORE I 'splained to you about the differences between the sliding caliper design and the multipot fixed caliper designs of Porsche and Brembo.

It doesn't matter how many f**king pistons you have, or how your caliper is designed. It is all about effective cooling and heat distribution of the brake system. The fixed caliper, 4-6 pot systems in Porsches designed by Brembo, are effective in spreading out the heat evenly through multiple caliper pistons and using a giant fixed caliper as a heat sink. If you look at the caliper, you can see only about 40% of that massive block is dedicated to the calipers, while the remaining 60% is DEAD WEIGHT to distribute heat.

There's another way to distribute heat. Build a massive rotor. Bigger rotor has several advantages. It's a rotating mass, therefore with proper venting it will dissipate heat quickly. Bigger rotors can also accomodate larger brake pads with large, single pistons, thus allowing larger sweep area and more brake torque. You can effectively build a system with large rotors that will brake and dissipate heat just as effectively as a mulit-piston fixed caliper system for a lot less. The disadvantage, of course, is using the rotor as a heat sink will shorten the life of the rotor and pad, where as the fixed caliper multi-pot will extend rotor and pad life because some of the heat is dissipated through the caliper AND the multipot caliper distribute the brake force evenly.

The key here, of course, is COOLING. You can run a 8 piston caliper on a 15" rotor, if you can not effectively pipe cool air to the brake system, it'll fade QUICKER than a 12" rotor on a single pot caliper with a nice cooling duct attached. You put that complicated cooling system on the 996 Turbo on say, the M5, it'll stop just as effectively time after time.
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  #77  
Old 06-02-2005, 12:16 PM
Shinkaze Shinkaze is offline
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Quote:
Originally Posted by SpeedFreak!
Max & Shinkaze,
I really do agree with this point... I understand the bottom line is money. I have said that all along. I never believed that it's Corporate Speak... as you have said... but is actually PEOPLES ideals and beliefs, BUT... when the support for these ideals and beliefs are no longer there in the consumer market... things will change.
Here opens the real debate between 2 very different camps. You believe that the Automatic "SLUSHBOX" transmission will replace the manual... I and many others in the car freak world... believe that the manual will NEVER DIE... and that the SMG will advance to the point where it replaces the current SLUSHBox... if for no other reason is a result of the need for greater efficiency then a "Fluid" driven system can produce. Where as the SMG will certainly reach a point where it can operate in Full Auto mode smoother then anything else. I know we are a long way from there now, but with advances in software and hardware, it won't be long and we'll be there.
Well that's the thing I regard the SMG as a type of Automatic. Yes it uses a clutch, yes you can manually tell the tranny when to shift, but the driver is no longer handling the mechanical activity of the shift. In the end though SMG is a Driver's aid for shifting, just as an Automatic is (not saying that's better or worse, just saying it's handing control of that aspect of driving to the car). In this regard I agree that SMG will converge with the traditional automatic, but I don't see one replacing the other, rather I see both replaced with a hybrid. Take the new Merc 7-speed Auto for instance it has a clutch'ed Torque Converter. Meaning it can give true clutch-engagment to the rear wheels bypassing the Torque converter. And you can shift it manually like an SMG. That said the internals are more evolutionary "automatic" than "manual" so I think folks here on the board consider it an Automatic. I feel this type of transmission (or some evolution thereof) could replace the Automatic and SMG.

Another example is the Audi DSG gearbox. Looking at it internally, it's more Automatic than manual, only it lacks a Torque converter. So what is it? Is it an Automatic with a double clutch? Again it's a hybrid device.

The bigger question is "will Manuals go away", I mean heck, manual brakes did and somewhere I'm sure there is someone lamenting not having the pleasure of feeling the brake pads squeal under their hand (maybe the parking brake is the vestigal reminder of those days). I hope they do not, as so far I ahve yet to be impressed by a Driver's aid that shifts for me.
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  #78  
Old 06-02-2005, 12:24 PM
Alex Baumann Alex Baumann is offline
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Quote:
Originally Posted by The HACK
Man I hope you posted this BEFORE I 'splained to you about the differences between the sliding caliper design and the multipot fixed caliper designs of Porsche and Brembo.

It doesn't matter how many f**king pistons you have, or how your caliper is designed. It is all about effective cooling and heat distribution of the brake system. The fixed caliper, 4-6 pot systems in Porsches designed by Brembo, are effective in spreading out the heat evenly through multiple caliper pistons and using a giant fixed caliper as a heat sink. If you look at the caliper, you can see only about 40% of that massive block is dedicated to the calipers, while the remaining 60% is DEAD WEIGHT to distribute heat.

There's another way to distribute heat. Build a massive rotor. Bigger rotor has several advantages. It's a rotating mass, therefore with proper venting it will dissipate heat quickly. Bigger rotors can also accomodate larger brake pads with large, single pistons, thus allowing larger sweep area and more brake torque. You can effectively build a system with large rotors that will brake and dissipate heat just as effectively as a mulit-piston fixed caliper system for a lot less. The disadvantage, of course, is using the rotor as a heat sink will shorten the life of the rotor and pad, where as the fixed caliper multi-pot will extend rotor and pad life because some of the heat is dissipated through the caliper AND the multipot caliper distribute the brake force evenly.

The key here, of course, is COOLING. You can run a 8 piston caliper on a 15" rotor, if you can not effectively pipe cool air to the brake system, it'll fade QUICKER than a 12" rotor on a single pot caliper with a nice cooling duct attached. You put that complicated cooling system on the 996 Turbo on say, the M5, it'll stop just as effectively time after time.
To a question why M cars have small and 'crappy' brakes, the M-GmbH manager Mr Bruhnke explained it exactly like you did above.
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  #79  
Old 06-02-2005, 12:37 PM
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Quote:
Originally Posted by Alex Baumann
To a question why M cars have small and 'crappy' brakes, the M-GmbH manager Mr Bruhnke explained it exactly like you did above.
Did he also specifically use the words "how many f**kin' pistons" too?

Did he also explain why the M cars have such crappy cooling for brakes? If you've ever seen Porsche cooling ducts, you'd be amazed why BMW doesn't do something similar. Stuka's 996 Turbo has the most effective brake cooling I've ever seen. Simple and very effective.
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  #80  
Old 06-02-2005, 12:39 PM
Shinkaze Shinkaze is offline
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Quote:
Originally Posted by SpeedFreak!
You, my track going friend, are the only one repeatedly taking this exclusively to the track. We have all been talking, especially myself, about ALL conditions.
No, I have been talking about street conditions as the failing of the SMG. SMG is a track technology more applicable to track type racing which may (if lucky) account for 1% of the driving conditions your average SMG equiped car will get to experience.
Quote:
I have driven, with SMG... which in ALL situations has been VASTLY superior. There is only one exception... that is when I want to drift, or drive really poorly... (j/k )
As a driver's aid I can aknowledge why some people like it. Just as DSC makes driving easier by divorcing the driver from certain aspects of driving so too does SMG. In some situations DSC makes you a better driver, in other situations, it slows you down and takes away your fun. Case in point I can't do a full throttle 1-2 shift in my M3 without my programed by Ralph Nader DSC slapping me on the wrists and killing power on the 1/2 shift. Sure it's safer I don't chirp the tires, but I can make the decision as to whether or not I can safely do a full throttle 1-2 shift. In that regard DSC slows me down, when it's raining buckets and I hit a patch of water, then DSC kicks in and keeps me straight. In that regard it's helpful.

SMG is a driver's aid as well, some are better for it, other's are not. If I could have SMG "some of the time" and full manual the rest, then I would be a strong proponet of the technology. Inability to "turn it off" and be a more fully engaged driver is at the core of my dislike of SMG and part of the reason I consider it as much fun as an Automatic. But that's just my opinion, YMMV
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  #81  
Old 06-02-2005, 12:44 PM
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Quote:
Originally Posted by Shinkaze
I ride a Sport Bike so trust me when I say I understand the *theory* of what you're saying. The *reality* is different. At the track you can plan perfect apexes etc, on the street conditions change so quickly so fast and in ways you can't don't anticipate, that your "high performance driving school" ideals are no longer absolutes.
Riding a sport bike doesn't mean you UNDERSTAND how to drive fast. I've seen more people who ride bikes who don't know sh*t about how to take a corner right, but since sport bikes are so light and nimble they never figure out what they're doing is WRONG.

Reality is EXACTLY like the theories taught in HPDEs, except the HPDEs take everything you see in real life driving and multiply it by 10X. You will see varying road conditions at a track. There are off camber turns. There are new pavements that are slicker than old, worn out pavements. There are oil slicks, dropped coolant, dirt, tire marbles, and rain you have to deal with ALL THE TIME. Imagine coming out of a 85mph sweeper and encountering slick COOLANT at the apex dropped by the car in front of you. My instructor friend Raffi had to deal with that. Did he shift? HELL NO. If you get all your braking and downshifting done before entering the turn, all you need to do is countersteer and modulate the throttle to get the car back under control.

I'm going to again beat you over the head with this: Get yourself to some HPDEs before you kill yourself. NEVER, ever shift in the middle of a turn.
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  #82  
Old 06-02-2005, 12:53 PM
Alex Baumann Alex Baumann is offline
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Quote:
Originally Posted by The HACK
Did he also specifically use the words "how many f**kin' pistons" too?

Did he also explain why the M cars have such crappy cooling for brakes? If you've ever seen Porsche cooling ducts, you'd be amazed why BMW doesn't do something similar. Stuka's 996 Turbo has the most effective brake cooling I've ever seen. Simple and very effective.
Yes, but he used some other lingo

As for the crappy cooling issue, this is the reason why the E60M5 came without fog lights, the whole front spoiler was tailored for more cooling. Is it as effective as the Porsche brakes? I don't know, maybe not, but I'm sure that the techies in Garching are capable of designing brakes like the ones in Porsche.
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  #83  
Old 06-02-2005, 01:04 PM
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I will say this one more time, whether you guys get it or not it doesn't matter.

Those of you who think that track driving skills can't or don't translate to street driving probably have never experienced real high performance driving. I drive using valuable skills I learn on the track everyday, and everyday I look around at drivers around me and am simply amazed a how these idiots stay alive on their daily commute. Same reason why everytime there's a little bit of fog or when it drizzles in L.A., traffic grinds to a halt because people simply can't grasp the simple concept of vehicle control taught in track schools. The very fundamentals of track driving, look ahead, be smooth with throttle, brake, and steering inputs, traction account, brake in a straight line, unwind steering as you accelerate...etc, all the VERY BASICS are not understood in daily driving. Because the conditions you face everyday in the "real world" never approach 5/10th what you experience on the track, you can get away with, say, shuffling your steering wheel in mid turn or braking/shifting in turns and it doesn't throw your car for a loop.

But varying conditions (say, the puddle of oil in the corner or sudden rain...etc) brings your car's capability down immediately to about 1/2 of what it's capable of, therefore, track training prepares you as a driver to face those type of situations because you are already used to experiencing the vehicle and yourself near the limit. And I will be the first person to tell you I am not that good of a driver. I used to think I am. Until I started doing the BMWCCA HPDEs, I start to realize that as a driver I have a very long way to go. Heck, I'm still an intermediate (B) student in the system, so I'm ahead of only half the drivers in the field while behind nearly the majority in terms of skills.

To answer your question RE: SMG vs. Manual in the middle of a turn with oil slick at the apex: Again, shifting is the last thing you should do here. Even with a real manual, the SECOND you clutch in and put the car in neutral, the car's rear end will lighten up and you will spin the car. No amount of clutch feathering will save your @ss. The advantage of having an SMG here, is that if you ABSOLUTELY need to downshift at the apex where there's some oil slick (still can't imagine why you would ever want to shift in a corner), the shift is executed immediately and you only lose power for a split second, and you can use throttle to control the vehicle or let the car's fancy electronics save your @ss.

Trust me. A 10-15% loss in throttle in those situations will force the rear end of a RWD car to swap around, much less a full de-clutch and trying to feather in the clutch. The last thing you want to do is stay off the power here.
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  #84  
Old 06-02-2005, 01:06 PM
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Quote:
Originally Posted by Alex Baumann
Yes, but he used some other lingo

As for the crappy cooling issue, this is the reason why the E60M5 came without fog lights, the whole front spoiler was tailored for more cooling. Is it as effective as the Porsche brakes? I don't know, maybe not, but I'm sure that the techies in Garching are capable of designing brakes like the ones in Porsche.
That was basically the big weak point in E46 M3s...And BMW NA had the balls to block what little cooling duct that's already there.

Maybe PhillipeK will be kind enough to take an E60 M5 out to the local AutoX course, when Irvine BMW gets one?
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  #85  
Old 06-02-2005, 01:23 PM
Shinkaze Shinkaze is offline
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Quote:
Originally Posted by The HACK
Riding a sport bike doesn't mean you UNDERSTAND how to drive fast. I've seen more people who ride bikes who don't know sh*t about how to take a corner right, but since sport bikes are so light and nimble they never figure out what they're doing is WRONG.
*sigh* Obvioulsy you've never owned a bike....

A motorcycle is very unforgiving and you can do things with a car that will get you killed on a bike. "Sport Bikes are so light and nimble..." It takes a thousand times more skill to ride a bike than drive a car. (That's actually a NHTSA fact, it takes 1,000 times more operations to ride a bike in street conditions than a car).

I'll sum it up by saying take your last sentance and just strike it out. You can do "Wrong" things in car. Those same "wrong" things will flat our kill you on a bike.
Quote:
Reality is EXACTLY like the theories taught in HPDEs, except the HPDEs take everything you see in real life driving and multiply it by 10X.
Now you're sounding like an academic. There is theory and then there is practice. Race Theory is not 100% applicable to Street practice. I'd challenge you to prove it as such.
Quote:
You will see varying road conditions at a track. There are off camber turns. There are new pavements that are slicker than old, worn out pavements. There are oil slicks, dropped coolant, dirt, tire marbles, and rain you have to deal with ALL THE TIME. Imagine coming out of a 85mph sweeper and encountering slick COOLANT at the apex dropped by the car in front of you. My instructor friend Raffi had to deal with that. Did he shift? HELL NO. If you get all your braking and downshifting done before entering the turn, all you need to do is countersteer and modulate the throttle to get the car back under control.

I'm going to again beat you over the head with this: Get yourself to some HPDEs before you kill yourself. NEVER, ever shift in the middle of a turn.
As a point of fact I have taken a couple of track days, lessons, etc and competed in Autocross in F-Stock way back "in the day".

Do you learn a lot in track driving? Sure.
Can you apply it to your street driving? Sure.
Do you adhere to those axioms in non-applicable conditions? No.

Track and street are two entirely different environments with their own set of needs and requirments. If you start track driving on the street you'll find yourself in a world of hurt.

Street Driving requires a higher level of flexibility and safety margin than track tenats allow. Case in point, if you hit a perfect Apex your Exit path puts you into oncoming traffic. Go ahead, try it, you'll find your suspension is loaded and your aimed into the traffic stream upon exiting the turn, good for maintaining revs and speed, bad for safety-margin and the street.

-Adam
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  #86  
Old 06-02-2005, 01:23 PM
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The HACK The HACK is offline
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Quote:
Originally Posted by Shinkaze
Well that's the thing I regard the SMG as a type of Automatic. Yes it uses a clutch, yes you can manually tell the tranny when to shift, but the driver is no longer handling the mechanical activity of the shift. In the end though SMG is a Driver's aid for shifting, just as an Automatic is (not saying that's better or worse, just saying it's handing control of that aspect of driving to the car). In this regard I agree that SMG will converge with the traditional automatic, but I don't see one replacing the other, rather I see both replaced with a hybrid. Take the new Merc 7-speed Auto for instance it has a clutch'ed Torque Converter. Meaning it can give true clutch-engagment to the rear wheels bypassing the Torque converter. And you can shift it manually like an SMG. That said the internals are more evolutionary "automatic" than "manual" so I think folks here on the board consider it an Automatic. I feel this type of transmission (or some evolution thereof) could replace the Automatic and SMG.

Another example is the Audi DSG gearbox. Looking at it internally, it's more Automatic than manual, only it lacks a Torque converter. So what is it? Is it an Automatic with a double clutch? Again it's a hybrid device.

The bigger question is "will Manuals go away", I mean heck, manual brakes did and somewhere I'm sure there is someone lamenting not having the pleasure of feeling the brake pads squeal under their hand (maybe the parking brake is the vestigal reminder of those days). I hope they do not, as so far I ahve yet to be impressed by a Driver's aid that shifts for me.
OMG there's so many things wrong with all your statements I don't even know where to begin.

First, ALL transmissions have clutches. How they're engaged is different. There's a friction/clutch disc attached to the other side of EVERY SINGLE automatic transmission. The only difference? An automatic transmission uses a planetary gear to select different gear ratios and a torque converter to buffer between the clutch and the transmission to allow for smooth gear transitions. Fancier automatics have lock-down ratios where in some gears the torque converter is LOCKED OUT and the transmission, clutch, and driveshaft become connected as one single power delivery to the differentials for maximum efficiency. The Merc. transmission is no fancier than any other automatic transmission, the only difference is the "brains" that control the planetary gear and how gears are picked.

The main difference between an auto and a manual, is that instead of using a planetary gear to shift gears up and down, a manual uses a mechanical selector and instead of having a torque converter to de-couple the transmission from the flywheel/clutch, a manual uses a hydraulic mechanism to push the clutch plates apart. The difference between an SMG and a manual is much smaller than the difference between an SMG and an automatic. SMG uses an electronic-hydraulic mechanism (but it is still a mechanical selector) to shift between gears, and uses the same exact hydraulic actuator to de-couple the clutch, except the hydraulic actuator is activated electronically and connected to the shift mechanism. The overall principles are the same, the fundamental differences are torque converter vs. hydraulic actuators, and mechanical selectors vs. planetary gears.

Audi's DSG is NOTHING like an automatic. No torque converter. No planetary gear to automatically select the up-coming gears. The DSG is basically an SMG type transmission where gears are selected electro-hydraulically and clutch actuated hydraulically, but it uses a dual clutch system whereby two sets of gears can be selected simultaneuously and it uses an electronic program to determine when and where to decouple the clutch and select the next gear. It may drive like an automatic, it may FEEL like an automatic, but it is NOT an automatic. It is still by all definitions, a manual transmission.

The Merc 7 speed is an automatic, and it doesn't shift like an SMG. Just because you can select your own gears doesn't make it an SMG. SMG means "sequential manual gearbox", and the manual portion indicate a hydraulic actuated clutch and a mechanical gear selector.
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  #87  
Old 06-02-2005, 01:26 PM
Andre Yew Andre Yew is offline
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Quote:
Originally Posted by Shinkaze
Okay so I'm hitting the apex of a turn and need to down shift to maintain revs, but I see there is a puddle in the road and realize for this one shift I'm going to need to be a little softer on the engagement to maintain traction. How does SMG know to do that? (i.e. vary Clutch engagement and agression turn to turn?) I don't want to mess with a little "firmness" button every time I hit new conditions that vary second to second as they often do on the street.
I find this disturbing for many reasons:

1. Why are you at 10/10ths in an environment as hazardous as you say it is? This is poor judgment.

2. Properly done downshifts are smooth --- clutch engagement, aggression, and available traction have nothing directly to do with it. What will disturb your car at the apex even before a bad downshift is lifting your throttle in order to perform the downshift.

As for brakes, many CCA club racers race with the stock hardware, and use only additional cooling ducts, better brake fluid, and race pads, so I think it's quite adequate. Larger rotors, all else being equal, always require more pistons. Having one massive piston for a large rotor has many mechanical disadvantages.

--Andre
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Old 06-02-2005, 01:37 PM
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Quote:
Originally Posted by Shinkaze
As a point of fact I have taken a couple of track days, lessons, etc and competed in Autocross in F-Stock way back "in the day".

Track and street are two entirely different environments with their own set of needs and requirments. If you start track driving on the street you'll find yourself in a world of hurt.
Doing track days doesn't mean you're learning anything, especially if you're not getting the proper instruction from the passenger side. Heck, I know a lot of people who goes to open lap days all the time, and none of them learned the proper mechanics of how to drive and they all think they're hot sh*t driver, only to be making the same stupid mistakes over and over.

I drive on the street like I drive on the track ALL THE TIME. The only difference is I dial my throttle and brake inputs way back down. I still do all the very basics of track driving, look ahead, be smooth with my inputs, hit my apex/track-out within the confines of my lanes...etc.

In reality, track driving requires a much larger margin of safety than street driving, because you ARE much closer to the limit of your skills and you are much faster, and the reaction time to mistakes and road conditions are much shorter than street driving. That is why simple track driving concepts translate so well to poor street conditions (except for potholes in the rain, but we won't elaborate on that), because the limits are closer and your reaction time is shorter.

Honestly, go take a few BMWCCA HPDEs or even BMW's own M Performance Driving School, or a Barbar/Russell/Daly type professional driving schools, and it'll open your eyes. Sounds to me like you've already picked up a lot of very bad habits from all your street driving and the limited track days and your bike riding days. It may save your life someday.
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  #89  
Old 06-02-2005, 01:38 PM
Andre Yew Andre Yew is offline
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Quote:
Originally Posted by Shinkaze
Street Driving requires a higher level of flexibility and safety margin than track tenats allow. Case in point, if you hit a perfect Apex your Exit path puts you into oncoming traffic. Go ahead, try it, you'll find your suspension is loaded and your aimed into the traffic stream upon exiting the turn, good for maintaining revs and speed, bad for safety-margin and the street.
Street driving requires more flexibility and higher safety margins, but your example is a very narrow, inflexible, dogmatic view of what you were taught on the track. Again, I have to ask why are you driving at such an extreme speed on the street to so fully load up your suspension that you've become only a passenger in your car? And why are you trying to drive into oncoming traffic?

--Andre
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  #90  
Old 06-02-2005, 02:02 PM
Shinkaze Shinkaze is offline
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Originally Posted by The HACK
OMG there's so many things wrong with all your statements I don't even know where to begin.

First, ALL transmissions have clutches. How they're engaged is different. There's a friction/clutch disc attached to the other side of EVERY SINGLE automatic transmission. The only difference? An automatic transmission uses a planetary gear to select different gear ratios and a torque converter to buffer between the clutch and the transmission to allow for smooth gear transitions. Fancier automatics have lock-down ratios where in some gears the torque converter is LOCKED OUT and the transmission, clutch, and driveshaft become connected as one single power delivery to the differentials for maximum efficiency. The Merc. transmission is no fancier than any other automatic transmission, the only difference is the "brains" that control the planetary gear and how gears are picked.
Thanks for the explanation. FWIW I've torn down a couple of transmissions so I'm very aware fo their internal workings.

Maybe you need to calm down and do some research first. The Merc 7-speed uses a locker-clutch so it can bypass the torque converter and lock the flywheel to the input shaft just as a true manual does.

Quote:
The main difference between an auto and a manual, is that instead of using a planetary gear to shift gears up and down, a manual uses a mechanical selector and instead of having a torque converter to de-couple the transmission from the flywheel/clutch, a manual uses a hydraulic mechanism to push the clutch plates apart. The difference between an SMG and a manual is much smaller than the difference between an SMG and an automatic.
Again where did I say othewise? Please provide a quote.

Quote:
SMG uses an electronic-hydraulic mechanism (but it is still a mechanical selector) to shift between gears, and uses the same exact hydraulic actuator to de-couple the clutch, except the hydraulic actuator is activated electronically and connected to the shift mechanism. The overall principles are the same, the fundamental differences are torque converter vs. hydraulic actuators, and mechanical selectors vs. planetary gears.
Again where did I say otherwise. Provide a quote.

In function an SMG acts like an automatic. In technical specification an SMG *IS* a ZF manual with a "shifter robot" taken care of the dirty work. Aston Martin uses this same principle on the T-56 6-speed SMG used on the Vanquish.
Quote:
Audi's DSG is NOTHING like an automatic. No torque converter. No planetary gear to automatically select the up-coming gears. The DSG is basically an SMG type transmission where gears are selected electro-hydraulically and clutch actuated hydraulically, but it uses a dual clutch system whereby two sets of gears can be selected simultaneuously and it uses an electronic program to determine when and where to decouple the clutch and select the next gear. It may drive like an automatic, it may FEEL like an automatic, but it is NOT an automatic. It is still by all definitions, a manual transmission.
Again where did I say otehrwise? please provide a quote.
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The Merc 7 speed is an automatic, and it doesn't shift like an SMG. Just because you can select your own gears doesn't make it an SMG. SMG means "sequential manual gearbox", and the manual portion indicate a hydraulic actuated clutch and a mechanical gear selector.
Funny you should point that out, as technically speaking the M3 SMG is not a true SMG. Since it's a non-sequential tranny forced into sequential duty.

Looking at your response above I can see you misread my post to say a SMG technically is an automatic. Maybe I wasn't clear I was speaking to functional operation only. If you actually read what I wrote you'll see I said that SMG trannies and true autos are technically different, but they will likely evolve into a hybrid of the two.
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  #91  
Old 06-02-2005, 02:06 PM
Shinkaze Shinkaze is offline
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Quote:
Originally Posted by Andre Yew
I find this disturbing for many reasons:

1. Why are you at 10/10ths in an environment as hazardous as you say it is? This is poor judgment.
re read my post. You can be safely driving on the street at 5/10ths and hit a scenario that puts you into 11/10s.
Quote:
2. Properly done downshifts are smooth --- clutch engagement, aggression, and available traction have nothing directly to do with it. What will disturb your car at the apex even before a bad downshift is lifting your throttle in order to perform the downshift.
So the response from the SMG crowd is "SMG is perfect for 100% of all driving conditions, and if a scenario is pointed out where a true manual is superior, then you shouldn't have gotten yourself into that situation to begin with".
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Old 06-02-2005, 02:19 PM
Shinkaze Shinkaze is offline
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Originally Posted by The HACK
Honestly, go take a few BMWCCA HPDEs or even BMW's own M Performance Driving School, or a Barbar/Russell/Daly type professional driving schools, and it'll open your eyes. Sounds to me like you've already picked up a lot of very bad habits from all your street driving and the limited track days and your bike riding days. It may save your life someday.
Sounds to me like you've done one or two track schools and think you're Mario Andretti now.

Okay I admit it, I'm a racing Noob I only have 4 SCCA Pro Solo II seasons under my belt and maybe 50 miles clocked at Road Atlanta. I've only attended 4 organized racing Schools, but even this very limited exposure was enough to visibly show the differences in environments. Maybe with more exposure to racing you'll see this too, dunno, maybe you need more study. One thing my instructors harped on was awareness of conditions. That tenant alone is enough to visibly magnify the differences between Street and Track.

I can almost see you now drawing out a turn on a sheet of paper, laying out the Proper Race Apex, and realizing..."Sh*t, Shinkaze was right, a race Apex does put me into oncoming traffic".

Your statement about motorcycles being more forgiving because of their "lightness and nimbleness" shows you have a lot to learn.
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Old 06-02-2005, 02:23 PM
Shinkaze Shinkaze is offline
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Originally Posted by Andre Yew
Street driving requires more flexibility and higher safety margins, but your example is a very narrow, inflexible, dogmatic view of what you were taught on the track. Again, I have to ask why are you driving at such an extreme speed on the street to so fully load up your suspension that you've become only a passenger in your car? And why are you trying to drive into oncoming traffic?

--Andre
I was pointing out to "The Hack" that using track school technique is dangerous on the streets. For example, a Race line through a turn is deadly to oncoming traffic (And you for that matter).

My Example about SMG and traction in a turn is you can be driving at 50% and think conditions are safe enough to execute a shift, only to find an unexpected item in the road etc mid shift. It's just a scenario.

The lack of Driver engagement in the Clutch process is IMOHO a weakness of SMG.
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Old 06-02-2005, 02:43 PM
Andre Yew Andre Yew is offline
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Quote:
Originally Posted by Shinkaze
So the response from the SMG crowd is "SMG is perfect for 100% of all driving conditions, and if a scenario is pointed out where a true manual is superior, then you shouldn't have gotten yourself into that situation to begin with".
No. Shifting at the apex when you're close to 10/10ths is problematic with either SMG or manual. However, you implied that roughness of the shift is what will primarily disturb your car's balance. This is wrong because:

1. Lifting of the throttle will affect your car well before you perform your downshift.

2. Properly-done downshifts with either a manual or SMG don't disturb your car, and proper downshifts are not directly affected by your traction conditions.

Quote:
Originally Posted by Shinkaze
I was pointing out to "The Hack" that using track school technique is dangerous on the streets. For example, a Race line through a turn is deadly to oncoming traffic (And you for that matter).
You don't drive some ideal line. You drive the road and conditions you're given.

--Andre
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  #95  
Old 06-02-2005, 02:54 PM
Shinkaze Shinkaze is offline
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Quote:
Originally Posted by Andre Yew
No. Shifting at the apex when you're close to 10/10ths is problematic with either SMG or manual.
That wasn't the scenario. Going in at 5/10ths, executing a shift and then encountering a low track condition that puts you at 10/10ths mid-shift.
Quote:
However, you implied that roughness of the shift is what will primarily disturb your car's balance. This is wrong because:

1. Lifting of the throttle will affect your car well before you perform your downshift.

2. Properly-done downshifts with either a manual or SMG don't disturb your car, and proper downshifts are not directly affected by your traction conditions.
No not shift roughness, rather the inability to control shift finess and agressivness corner to corner depending on conditions. The SMG cannot do that, a Manual can.

It's my understanding (which could be wrong) this is one reason that SMG cars are slower at the drag strip as well (inability to modulate clutch to maximize launch off the line). I recall an article from BMW magazine where they tested an SMG with Launch control against a 6MT and run after run the 6MT was faster to the 60 foot mark.
Quote:
You don't drive some ideal line. You drive the road and conditions you're given.

--Andre
Exactly my point.
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Old 06-03-2005, 04:04 AM
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tierfreund tierfreund is offline
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I must say, this has turned out to be a very interessting thread (/much more than the title suggests). I cant say that I can follow every arguement and its rather hard to figure out whos right and hows wrong (or more right and more wrong), but Im amused and learning new things by the line. Thanks for sharing you opinions and views. It makes bimmerfest worth the while.

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Old 06-03-2005, 08:23 AM
Alex Baumann Alex Baumann is offline
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Originally Posted by tierfreund
I must say, this has turned out to be a very interessting thread (/much more than the title suggests). I cant say that I can follow every arguement and its rather hard to figure out whos right and hows wrong (or more right and more wrong), but Im amused and learning new things by the line. Thanks for sharing you opinions and views. It makes bimmerfest worth the while.

In these kind of discussions there is no right or wrong, it all comes down to the personal preferences. Manual transmission is a way of life, it is about how you control the whole driving experience, throttle, clutch, shift knob etc. No other transmission type can give me a similar pleasure in a high-performance car.
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  #98  
Old 06-03-2005, 08:39 AM
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tierfreund tierfreund is offline
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Quote:
Originally Posted by Alex Baumann
In these kind of discussions there is no right or wrong, it all comes down to the personal preferences. Manual transmission is a way of life, it is about how you control the whole driving experience, throttle, clutch, shift knob etc. No other transmission type can give me a similar pleasure in a high-performance car.
True, but this discussion has actually wandered even further into serious driving dynamics. And thats fun to watch (and educational as well). Only hard to tell whos wrong and whos right since some statements are contradictional.

Oh and by the way, I understand the pleasure you find i managing a manual shift. I find that too. But theres a level of driving pleasure in SMG that you only find after quite some experience with it. Its not that it shifts better than you personally could, it shifts about as well as a very good driver can. And then at frees your mental capacity to further enhance your actual driving. Its really hard to explain and hard to anticipate until youve been there. And you can only get there by driving SMG a lot. Which is whay, I believe many SMG owners (at least the ones willing to dig into it) become lifetime fans. True, you loose the pleasure of a shift you yourself have well executed. But you gain the pleasure of marvelous smooth yet rapid driving you can achieve thanks to the spare mental capacity you have with somebody else doing the clutching. Part of that pleasure can even be found in maximizing the use of an auto box. But then auto boxes with their torque converters distance you from the actual drive so much that precision driving becomes more difficult again.
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