[lemetier]

Originally Posted by 10"

Lol...even the lesser DCT transmissions are better than the best torque converted slushboxes. It's all mechanics in the end. Dual clutch transmissions will always be more satisfying and with better control than those crappy ZF boxes. The only reason ZF boxes are used so often now is COST. The end. If you're worried about milliseconds you're doing it wrong...it's about how it feels not the technicality of undetectable numbers. That's why manual gearboxes are the most satisfying and slowest...

Cost really does not play a factor (approx $18 difference between the MDCT and 8HPTU2). To me and many others, a really slow automated manual does ruin the feel. 600ms is 0.6seconds; a very noticeable lag time, especially when that's the fastest the base ZF 7DT can change between sub-transmissions. In auto-mode it's 1sec up, 2sec down.

Originally Posted by CanAutM3

The 8AT has much more rotating mass inertia and drivetrain loss than a DCT making for a more sluggish drivetrain. A DCT is the better performance option. There is a reason why all high end hyper cars still run DCT.

Surprisingly, the 8HPTU beats MDCT in rotational mass and parasitic loss. I saw you noticed the ZF 8DT PDK is not a single axis main shaft transmission (configured more like one would see in a transverse layout because of the packaging issues encountered). This makes it very wide and tall to leave room for the abnormally large diameter clutch modules and electric motors on hybrid models. It's also rather heavy.

Originally Posted by eeyang92

Maybe no one but the engineers know, but is there some unspoken rule that the M3 need to get longer and longer every generation?

That being said, the rear wheel steering should cause the car to feel and behave as if it had a shorter wheelbase. Still, it would have been nice to have M2-like agility in sedan form.

Not just the M3, but all cars tend to grow with each successive generation simply because the avg adult height increases roughly 15mm every decade.

Originally Posted by BlackJetE90

+1

There is a reason McLaren, Ferrari, Porsche cars all use DCT. It is superior. No autobox fires up and down through gears like the PDK-S in a GT3 RS.

Maximum engine speed is why. There is one "autobox" unlike any other that beats them all....

The ZF 8PR (8HP without Torque Converter and internal race start clutch).

[CanAutM3]

Originally Posted by lemetier

Cost really does not play a factor (approx $18 difference between the MDCT and 8HPTU2).

IMO it is more a question of development and logistics costs of having a single transmission across the model line, more than the unit cost.

Originally Posted by lemetier

Cost really does not play a factor (approx $18 difference between the MDCT and 8HPTU2). To me and many others, a really slow automated manual does ruin the feel. 600ms is 0.6seconds; a very noticeable lag time, especially when that's the fastest the base ZF 7DT can change between sub-transmissions. In auto-mode it's 1sec up, 2sec down.

It depends what one refers to when talking "shift time". What matters to performance, it is the time in which the power transmission to the drive wheels is interrupted. In the case of a DCT, it is actually zero, so an AT cannot really beat it in that respect.

My understanding of the shift times we see quoted is the time it takes for one clutch to fully engage while the other is fully disengaged, and that is not really irrelevant to performance. What does impact the feel is the response time, the time between driver input and gear change.

Originally Posted by lemetier

Surprisingly, the 8HPTU beats MDCT in rotational mass

I really struggle believing that just looking at the general design of a planetary transmission. You have the whole carriers, multiple clutch packs and planet gears moving and rotating about. Much more mass rotating around.

[Frank Jia]

Wish four wheel drive system from M5 could become an optional choice in the future.

[stvding]

Originally Posted by M3 Adjuster

what's with the arbitrary 500 hp demand ? " SHOULD BE"

Should be what? Why? because you want it? You will get get 465 and like it..

I won't

[antzcrashing]

So what you are saying is: its going to be expensive

[lemetier]

Originally Posted by CanAutM3

IMO it is more a question of development and logistics costs of having a single transmission across the model line, more than the unit cost.

This is true when there is a large enough model line to spread it across. If the G8x is available with a manual, any savings is wiped out due to the separate certification costs. With the F8x, MT and DCT qualified for substantially similar rules and thus did not have separate Type Certificates and expense beyond unit costs.

Originally Posted by CanAutM3

It depends what one refers to when talking "shift time". What matters to performance, it is the time in which the power transmission to the drive wheels is interrupted. In the case of a DCT, it is actually zero, so an AT cannot really beat it in that respect.

My understanding of the shift times we see quoted is the time it takes for one clutch to fully engage while the other is fully disengaged, and that is not really irrelevant to performance. What does impact the feel is the response time, the time between driver input and gear change.

There's a bit of a myth regarding "power interruption". This reference is always against a MT or single clutch AMT. DCT's do have an interruption of power transfer as both clutches cannot be fully closed at the same time, but this is often masked by an DME induced pre-shift torque bump to mimic a Planetary overlapped clutch-to-clutch shift.

Originally Posted by CanAutM3

I really struggle believing that just looking at the general design of a planetary transmission. You have the whole carriers, multiple clutch packs and planet gears moving and rotating about. Much more mass rotating around.

I too struggled with the idea at first, but finally came to understand. There are fewer gear-sets and the mass is closer to the center of rotation. Because DCT runs with most of the gearset clutches open, this causes parasitic loss as that mass is free-wheeling rather than contributing to power transfer. With the ZF 8 speed planetary, only two shift elements are open at any one time, and have additional electric operators for lower friction loss. This is only for 3rd Gen and later 8HP BTW. The first two were not quite the same.

IMO, the G8x should be the first M's to incorporate E-Assist since the 48V electrical system is there anyway and the rumor mills have been speculating a "KERS" system for more than a decade. Using the 8P55R with integrated startup clutch combined with the 50hp/200nm Electric Module instead of a Torque Converter, the engine can still be somewhat high-revving, vastly more efficient, and provide a higher and more versatile power-band without having to go AWD.

[CanAutM3]

Originally Posted by lemetier

This is true when there is a large enough model line to spread it across. If the G8x is available with a manual, any savings is wiped out due to the separate certification costs. With the F8x, MT and DCT qualified for substantially similar rules and thus did not have separate Type Certificates and expense beyond unit costs.

But what if the same transmission is used across the entire BMW lineup?

Originally Posted by lemetier

There's a bit of a myth regarding "power interruption". This reference is always against a MT or single clutch AMT. DCT's do have an interruption of power transfer as both clutches cannot be fully closed at the same time, but this is often masked by an DME induced pre-shift torque bump to mimic a Planetary overlapped clutch-to-clutch shift.

While a clutch slips, it is still transmitting power. During a DCT shift, the two clutch are slipping against each other, with the higher gear clutch progressively pulling more and more on the lower gear clutch.

Originally Posted by lemetier

I too struggled with the idea at first, but finally came to understand. There are fewer gear-sets and the mass is closer to the center of rotation. Because DCT runs with most of the gearset clutches open, this causes parasitic loss as that mass is free-wheeling rather than contributing to power transfer. With the ZF 8 speed planetary, only two shift elements are open at any one time, and have additional electric operators for lower friction loss. This is only for 3rd Gen and later 8HP BTW. The first two were not quite the same.

I am sorry, but I am still not buying it. Just look how much mass is rotating away from the the center of rotation on ZF 8HP. The DCT has just as much "free wheeling" than any standard MT has. It is just the mass of the clutches, gears and shafts rotating.

[raysspl]

Cannot. Wait.

[jmg]

Originally Posted by stvding

I won't

A Hellcat can get you 500hp for much less money. You can get one of those if you like.

[frankiebones]

Originally Posted by ChrisK

My only concern is growth of this chassis, in length and width. The 3 series keeps growing.

I am not overly concerned about 2 inches in length. width should improve grip, no?

[frankiebones]

Originally Posted by jmg

If you really want a sleeper just get an M3 and take the M badges off. No one outside of the enthusiast world can tell the difference between a 3 series and an M3.

No one really prefers sleepers. They prefer the price of a "sleeper."

[frankiebones]

Originally Posted by somer

I'd say all this information is to be expected and not exciting one bit. Same engine is boring, automatic also boring, theres also a zero percent chance this next M3 looks better than the F80 M3. I'd say expect a smaller 5 series from what we've seen. I'm sure they'll manage to make the engine sound a little bit better but not completely.

Underwhelming news for sure.

Who pissed in your cheerios man? We get to keep a manual transmission! thats amazing!

Also, the new 5 series (and corresponding F90 M5) is a vast improvement aesthetically over the last gen.

While the G80 has much bigger shoes to fill (f80 is one of the best looking cars in history), if BMW could improve the 5 series to the extent they did, I think the G80, with updated headlights/taillights, aggressive front and rear bumpers, and flared out rear fenders would look amazing.

[Fraggy]

Originally Posted by Arcades

MT and full Auto huh...

RIP DCT. F80 seems to be the last with the M-DCT

I'm ok with that. I've grown to HATE the DCT in my car.

[dmboone25]

Originally Posted by Fraggy

I'm ok with that. I've grown to HATE the DCT in my car.

Really? Any particular reason why?

My last two cars have been PDK/DCT and I really enjoy them (previous 8 cars were all manuals).

I am not excited about the loss of DCT in the next gen M cars...I will be looking to scoop up an M2C at the end of my F80 lease for this exact reason.

[eMvy]

Originally Posted by stefan

I never enjoyed my S65.

Prior to you, said no one ever.

[AchtungF80]

Originally Posted by alex2364

This isn't going in the right direction. Is this going to be a BMW or Lexus?

Drive an E30 M3 and see if going in the right direction really is the right direction.

As long as they don't mess with the driving dynamics while making the ride more supple and compliant...why not.

[dmboone25]

Originally Posted by eMvy

Prior to you, said no one ever.

Very cool engine for sure - but never enjoyed it as much as the S54. Thought it was a bit of a lazy revving engine in comparison...but I can see why people love it.

[stefan]

Originally Posted by eMvy

Prior to you, said no one ever.

Not really man. you will find many ex e92 owners on other boards. The S65 shines at the track and really that's about it. even for spirited canyon runs it just doesn't have the torque. combined with the size and mass of the e92 it makes it feel very sluggish at low speeds. S54 seemed better matched to it's chassis as did the S62.

[uniqueMR]

Bravo. Cannot wait for new M

[eMvy]

You guys are correct in a number of ways. The S65 is a bit anemic in the torque department. You really have to understand how to work the engine. Sound and revs made up for it. I've been behind a S54, but it was making between 800-900 HP with the gas at the time, made the cover of euro magazine. Scary fast, not NA, and would love to drive a S54 in it's pure form.

Just like the beauty of 8 octaves on a piano, the S65 sings with her 8 throttle bodies.

[upsidedownfunnel]

Originally Posted by frankiebones

No one really prefers sleepers. They prefer the price of a "sleeper."

Of course I prefer buying a car that costs less that fulfills what I want. However, I absolutely prefer sleepers. I am a person that bought a Chevy SS. I bought a Sport Line 335i. I don't care for being flashy, and if you can't understand that, then maybe not everyone is like you.

I'll "reluctantly" buy an M3 if necessary. It is still an awesome car but I absolutely hate driving a flashy car to work or being seen in a flashy car with my family. Of course I'll enjoy the car, I'm not saying I won't. Just personally for me, I'd prefer to get an M340i which is more than enough for a fun daily driver.

[upsidedownfunnel]

Originally Posted by stefan

Not really man. you will find many ex e92 owners on other boards. The S65 shines at the track and really that's about it. even for spirited canyon runs it just doesn't have the torque. combined with the size and mass of the e92 it makes it feel very sluggish at low speeds. S54 seemed better matched to it's chassis as did the S62.

A lot of people also prefer NA high-revving motors with linear power delivery. Neither is inherently better than the other. You don't need a track to appreciate an engine like that.