[RPM90]

Originally Posted by chrisny

Early on that was the case but today's AWD systems are much better allowing no drop off and sometimes performance improvements as others have said.

Frictional losses increases as speed increases.
From standstill friction loss is zero and then climbs as speeds increase once the whirly bits get moving.

With all wheels available to pull from a standstill AWD has a launch advantage. But, typically you start to see the frictional drag as speeds climb.
The EVO and STI are monsters on a launch, but they suffer getting slower once beyond 90+mph.
Great stop light to stop light cars though.

[RPM90]

Originally Posted by Elk

The car has insufficient power for this to be an issue.

Not sure what you mean by that.
Please explain.

[RPM90]

Wheel/tire sizes used in testing could/might account for some of that.
Or, they could have used stickier compound tires for this round of testing.
But then the MT's should have also improved, if tire compounds are a factor.

Maybe they used a different launch technique with the AT's?
Most manufacturers list conservative accel times as compared to some car mag reviewers.

[ATX78703]

Originally Posted by RPM90

Most manufacturers list conservative accel times as compared to some car mag reviewers.

Agreed, which makes the 5.1s RWD / 4.8s AWD very aggressive quotes given that BMW usually lists times that are 0.3-0.5s slower than the mags.

[Elk]

Originally Posted by RPM90

Not sure what you mean by that.
Please explain.

A real "launch control" is needed only when wheelspin is difficult for the driver to modulate when the engine is producing a significant amount of power.

An F30 has insufficient power for this to be an issue. Even with run flats and a MT it is a challenge to get anything other than a cute chirp from the tires. Especially with an MT, all one need do to get maximum acceleration is to hold the brake, increase the revs, release the brake and floor the foot feed. Brainless.

A 16 year-old girl would sweep bracket racing at the drags with an F30. Seriously; lightening fast reflexes combined with an easy to control, consistent engine/AT combination is tough to beat.

[RPM90]

Originally Posted by Elk

A real "launch control" is needed only when wheelspin is difficult for the driver to modulate when the engine is producing a significant amount of power.

An F30 has insufficient power for this to be an issue. Even with run flats and a MT it is a challenge to get anything other than a cute chirp from the tires. Especially with an MT, all one need do to get maximum acceleration is to hold the brake, increase the revs, release the brake and floor the foot feed. Brainless.

A 16 year-old girl would sweep bracket racing at the drags with an F30. Seriously; lightening fast reflexes combined with an easy to control, consistent engine/AT combination is tough to beat.

The LC thing, I was just jokingly speculating about it, considering the 328i sped up by .1 sec and the 335i by .2. So with nothing changed that's pretty good, and begs the question as to how and why this is true. Both 328i and 335i MT times remain the same.

Regarding your comment, "especially with an MT..." and launching it, I'm sure you meant to write "AT"? I think you did, because I'm sure you know that you don't hold the brake, increase revs, and let it rip with MT.

The following is just thought exercise.

True, wheel spin control at launch is very important for fastest 0-? accel.
I can accept your argument, maybe, for the 328i with the N20, but not so much for the 335i N55.
I need to temper that comment by saying that I have not tried any full throttle standing starts in either version with AT.

I haven't driven the 335i MT, but in my 135i MT there is more than enough power to spin the tires from a standstill, slowing acceleration.
To do so, turn off DSC and traction control, and spin if not done properly.
With the N55 as well, there is plenty of power to do that.
Evidenced by BMW, which offers the DCT in the 135i N55, and it has LC.
It is effective as it gives a faster 0-60 when using LC.

So, let's discuss launching the AT.
What you describe is a "brake torque" technique where you hold in the brake, apply throttle to increase revs, then release the brake, and GO.
Does the 328i have enough power to break the rear tires loose with traction control completely off?
You say it doesn't. I've never tried it.

Questions:
Does the F30 allow the driver to have both the brake and throttle engaged at the same time for brake torquing?
Some cars don't allow it. If you're on the brake, throttle gets cut.

Let's say it does allow brake torque.
The N20 has nearly 260lb ft of torque by around 1300rpm.
If you brake torque the N20, how high will the revs climb?
If the trans stall speed doesn't allow engine rpm to go much higher than say 1000-1200rpm, then the engine isn't going to develop the full power it needs for a hard/er launch.

If stall speed is increased to say between 1500-2000rpm, then there should be plenty of revs to build boost and get a harder launch.
If there were some type of LC with AT, the driver will have to turn off traction control completely, hold the brake, floor the throttle, and simply let go of the brake. Simple, just like LC with real clutch type automatics.
Perhaps with LC, lockout is engaged immediately, thus allowing for better power transfer. Don't know, just speculating. This new ZF AT is pretty amazing as it has a very low speed lock out. IIRC, it's something like 22mph.

The 335i MT likely has more than enough power to spin it's tires on launch.
When brake torquing the 335i sport AT, at what rpm will it go to?

I bring LC with an AT because of this new ZF AT. It's efficiency rating brings it to MT levels. In older torque converter AT's, drive line loss could be much higher than with a MT. Now, that has greatly changed, and power transfer is nearly the same.
There is also much better, quicker, connection to the engine through very low mph/rpm lock out. That's a major factor in why this AT feels so connected to the engine, not "slush box" like at all.
Plus, 200 millisecond up shifts, and I just read that it achieves 100 millisecond down shifts!

It would be good to find out why accel speeds increased.
It'll be interesting to see if future tests show the same .1/328i and .2/335i second 0-60 improvement., as well as quicker 1/4 mile.
We've already seen 4.7 0-60 as the best tested time with the sport AT.
I wonder if we'll see 4.5?!
I'm sure when the mags get their hands on the Msports we'll get the results. It'll give them a reason to do more tests and comparo's.

[tojo_m]

I just ordered a 2013 335i (No Lines). I test drove the 2012 335i (Luxury Line). The 2012 335i was rated at 5.4s for 0-60, while it is 5.1s for the 2013. Does this really mean that the 2013 may be faster than the 2012? Or is BMW's marketing dept playing mind games with me?

[zeezz]

Originally Posted by tojo_m

I just ordered a 2013 335i (No Lines). I test drove the 2012 335i (Luxury Line). The 2012 335i was rated at 5.4s for 0-60, while it is 5.1s for the 2013. Does this really mean that the 2013 may be faster than the 2012? Or is BMW's marketing dept playing mind games with me?

I would guess marketing, since there were no changes to the chassis or engine for 2012 to 2013. In fact, the production lines barely had any downtime, since the 2012's were made all the way up to end of June and the 2013s began first week of July.

[RPM90]

Originally Posted by zeezz

I would guess marketing, since there were no changes to the chassis or engine for 2012 to 2013. In fact, the production lines barely had any downtime, since the 2012's were made all the way up to end of June and the 2013s began first week of July.

It's a tough call as to why the 335i AT times improved by .3, that's a substantial difference.

BMW hasn't been known to "lie" about their engine output or their accel times. If anything, they tend to give conservatives numbers so as to not over promise and under deliver.
Their engines always show better stock power output on customer done dyno's. And their accel times typically show better than what the factory lists.

Maybe they 'brake torqued' the AT this time, and/or turned traction control completely off.

We should send a letter to the car mags asking them to look into it?

[RPM90]

Originally Posted by ATX78703

I was perusing the new configurator and noticed that bmw has posted new 0-60 times for all the models, including xdrive. Somewhat interesting:

328i MT 5.7s
328i AT 5.8s
328i xdrive (AT only) 5.7s

335i MT 5.4s
335i AT 5.1s
335i xdrive MT 5.1s
335i xdrive AT 4.8s

3 observations - 1)no surprise about the grip advantage for xdrive, 2) confirmation that the AT is faster on the 335i, 3) surprised they are not offering 6MT on 328i xdrive

Do you recall the weights listed for 2012 models?
I seem to be recalling that the weight difference between the base 328i and base 335i as being a bit more than the current listing of 145lbs.
If it is different, it's likely due to the added base features, which the 328i got more of.

[Mako]

Originally Posted by ATX78703

With the new high torque engines (and yes, even 255 lb-ft at 1250 is considered high torque), AWD will have the advantage out the hole esp with good tires - its just a traction issue. Most of that advantage is in the 0-30 mph, prob even at 30-60mph, and I'm sure the RWD will pull ahead 60-100 mph.

I dont want to get into a AWD vs. RWD discussion, but with the shoehole difference provided by xDrive, the 335i xDrive with 8AT now launches faster than the S4 DCT (4.8 vs. 4.9s) which is always one of the things that S4 fans like to throw in your face.

I was more interested in the tranny differences and why the 0-60 times got revised so much. I mean these are faster than the e90 times they used to post.

A few magazines have tested the S4 0-60 at 4.5-4.6 seconds.

[ThreeThirtyFiveI]

BMW is notorious for sandbagging their 60 times. It only makes them look better when their cars out perform their estimations. They don't want to be like Cadillac with posting their 3.7s with a big * next to it.

[Mako]

Originally Posted by ThreeThirtyFiveI

BMW is notorious for sandbagging their 60 times. It only makes them look better when their cars out perform their estimations. They don't want to be like Cadillac with posting their 3.7s with a big * next to it.

Except that in the current 335i, car and driver could only get 5.3 seconds 0-60 which is what BMW claims...

All German manufacturers are conservative with their 0-60 times though, Mercedes, Porsche, Audi included (AMGs are always tested faster than Mercedes claims, same with Porsche 911s) Maybe in Germany the conditions just don't allow them to go as fast 0-60

[ATX78703]

Originally Posted by Mako

A few magazines have tested the S4 0-60 at 4.5-4.6 seconds.

i was using manufacturer times, b/c that is apples-to-apples. magazine times are a whole different ballgame.

[ATX78703]

Originally Posted by zeezz

I would guess marketing, since there were no changes to the chassis or engine for 2012 to 2013. In fact, the production lines barely had any downtime, since the 2012's were made all the way up to end of June and the 2013s began first week of July.

i think there maybe some differences in std equipment (tires would make a big difference), but really I think the MY 2012 was rushed out so fast that they didn't really provide real test numbers, just some estimates. Remember, the whole EPA ratings on the economy. I think these are the real numbers now.

[Mako]

Originally Posted by ATX78703

i was using manufacturer times, b/c that is apples-to-apples. magazine times are a whole different ballgame.

manufacturer times are not apples to apples, especially when talking about different manufacturers, even BMW has numbers all over the place, some of their cars (X3 35i) test exactly what they say (5.5 seconds, by BMW and magazines) and others (M3, old 335i) test much faster by the magazines. It seems like BMW's numbers are starting to be more in line with magazine numbers, maybe they are taking a page out of Cadillac's book! Although I believe the M5 was rated 4.2 or something like that and has tested at 3.7. I think they are still more conservative with the high performance cars than the standard models for some reason.

[RPM90]

Originally Posted by Mako

Except that in the current 335i, car and driver could only get 5.3 seconds 0-60 which is what BMW claims...

All German manufacturers are conservative with their 0-60 times though, Mercedes, Porsche, Audi included (AMGs are always tested faster than Mercedes claims, same with Porsche 911s) Maybe in Germany the conditions just don't allow them to go as fast 0-60

Even C&D in that review questioned if something may have been wrong with the car.

Road & Track achieved a 4.7, HUGE difference.
Compared to other tests, including R&T, C&D had the slowest tests, so it's likely something wasn't right.

BMW not claims 5.1 for the 335i AT. .3 sec quicker than previous estimate.

[dopper99]

Originally Posted by RobUK

328i 0-60 times on the BMW UK site are still 5.9s (manual) and 6.1s (auto). Maybe it's the rubbish roads we have over here... you can't do 0-60 on a UK road without having to swerve to avoid a pothole!

No, the UK website shows 0-62 (or 0-100kph) times. The bmwusa website shows 0-60. This is why the UK website figures appear to be slower than the ones discussed in this thread.

[RobUK]

Originally Posted by dopper99

No, the UK website shows 0-62 (or 0-100kph) times. The bmwusa website shows 0-60. This is why the UK website figures appear to be slower than the ones discussed in this thread.

Then if BMW's (revised) figures are to be believed, the auto-equipped 328i takes 0.3s to go from 60 to 62mph. Not disputing it, just curious I.e.

BMW USA (0-60)
- 328i AT 5.8s

BMW UK (0-62)
- 328i AT 6.1s

[CoolDude196]

Originally Posted by adelphi_sky

I noticed some of the videos on YouTube were posting faster 0-60 times than what was originally posted. Not sure how they goofed on the numbers. I thought these cars were thoroughly tested. Or perhaps they did some engine tweaking on the 2013s?

BMW always use the 'worst case' figures. They're always better in realty than according to the BMW figures.

[verbs]

Originally Posted by RobUK

Then if BMW's (revised) figures are to be believed, the auto-equipped 328i takes 0.3s to go from 60 to 62mph. Not disputing it, just curious I.e.

BMW USA (0-60)
- 328i AT 5.8s

BMW UK (0-62)
- 328i AT 6.1s

Is there a shift somewhere in there?

[xDrive35i]

[quote=RPM90]

Originally Posted by zeezz

I would guess marketing, since there were no changes to the chassis or engine for 2012 to 2013. In fact, the production lines barely had any downtime, since the 2012's were made all the way up to end of June and the 2013s began first week of July.[/QUOTE=zeezz;12275648]

It's a tough call as to why the 335i AT times improved by .3, that's a substantial difference.

BMW hasn't been known to "lie" about their engine output or their accel times. If anything, they tend to give conservatives numbers so as to not over promise and under deliver.
Their engines always show better stock power output on customer done dyno's. And their accel times typically show better than what the factory lists.

Maybe they 'brake torqued' the AT this time, and/or turned traction control completely off.

We should send a letter to the car mags asking them to look into it?

If somebody told me that BMW shifted their conservative acceleration numbers a little bit after seeing how quick the F30 was in testing, I'd believe it. Notice that even though the magazines are posting these radically quick times, BMW's official posted times are still more conservative. They gained a little perspective from the mags and changed their official times to draw in potential buyers who care about 0-60 times enough to check mfr. claims, but don't care enough to check the magazines.