Back in time

[neilum]

Originally Posted by EricSMG

My E90M is a manual and it's very good. However, the upper end of the powerband is very narrow (about 1.5k rpm or so) and I find the gear spacing of the manual results in each upshift dropping the revs a little too far such that the motor isn't kept in its sweet spot.

For example, if I shift at redline, the rpms drop to somewhere in the low 6s. That's too far since the powerband doesn't really come on until just before 7k.

The DCT with its much closer tranny ratios should result in a smaller rpm drop between shifts and thus keep the motor in the band at all times if shifted at redline. I haven't tested this to be sure but I bet it's the case, hence why the DCTs are faster.

Now, having owned a 6MT E90M, I would go DCT if I could do it over even though the manual is very good. I'm more about "effective" than purely "involvement".

Cool thing about a V8 with ITB's is it sounds great either way!

[EricSMG]

Originally Posted by BOOF-M3

I'll test this out on my DCT today and update.

Interested in your results. I'm betting an upshift from 2nd to 3rd, at redline, drops the rpms to the high 6k rpms.

If so - that's ideal for the stock S65's power curve. You want to be between 6.7k and redline at all times for max acceleration.

[Montaver]

Originally Posted by EricSMG

Meh, I was turned off by the manual. The massive on/off nature of the motor needs constant load to operate properly and thus, in my opinion, the DCT is vastly superior. It's very laggy below 3k and then WHAMO!! huge torque wall and then you lift to upshift and it's like you're falling off a cliff, then clutch out back on the gas... and then WHAMO!!.

No thanks.

DCT just let's you keep your foot down which means constant boost which means seamless acceleration. I know that isn't the "cool kids" answer, but it's the truth. It's a more effective combo for turbo motor. You want to be cool, you get the manual. You want a combo that really works well, you get the DCT

I do like the F80 ZCP overall, though. Ultra responsive, razor sharp car and drop dead gorgeous. I honestly think it'd be too aggressive to drive everyday - too hard edged and hard riding. My EDC/220M E90M is borderline and the F80 ZCP was significantly more hard edged. But I would love to have one three days a week

My e90 is DCT, it's an awesome gearbox. When in full attack mode around there is no doubt it's easier to drive fast than a manual. I like the way you can seamlessly downshift through multiple gears without unsettling the car allowing you to focus on the road. Also to your point the gearing is shorter so you are closer to peak output all the time.

I really miss driving a manual car though, if I had the luxury of two cars I'd buy a smaller sports car (Cayman, Elise) for that purpose. I might change at some point, but I wouldn't buy the same car again so i'm looking at alternatives. It needs to be practical so the aforementioned are out. I'm basically looking at either an f8x M3 or an M2. I really need to drive both to determine if it would be worth changing but havnt had the opportunity yet. In the interim I'm just going to rent manual cars on Turo every now and then, there is a 0 option manual Cayman close by for $135 so I might just take that out for a day to scratch the manual itch!

[BOOF-M3]

Originally Posted by EricSMG

Interested in your results. I'm betting an upshift from 2nd to 3rd, at redline, drops the rpms to the high 6k rpms.

If so - that's ideal for the stock S65's power curve. You want to be between 6.7k and redline at all times for max acceleration.

Sorry for the delay. Three of us set out today to put your theory to the test. No, not really, we met up and hit some quiet roads this morning. But I did test it out.
Wow, I am stunned by what I saw and felt. First I drove another members E92 6MT. The first two 1st gear redline shifts she would drop to 5,500 in 2nd. Third try I think I hit the redline perfectly and she dropped to 5,750 ish Rpm's.

Then got into my E92 DCT. Before I say where the Rpm's started out in 2nd I must say that the power difference was night and day. You were right, the DCT power felt completely different than the 6MT at the 2nd gear starting point. I hit my first shift manually and I was at 6,700 Rpms when she dropped into 2nd gear. Next try I was about perfect at redline and she dropped to 6,900 when starting 2nd. I then put it in D and floored it and it shifted right at 7,000. So I'm guessing that a perfect redline shift manually should also put her at 7,000.

The difference between starting 2nd at 5,750 and 6,900 is night and day.

All three of us drove the 6MT. As a side note and you had to see this coming if you know me, all three of us said that the DCT was a better driving experience. And that included the owner of the 6MT.

Did I enjoy driving the manual? You bet your sweet A$$ I did. I just enjoyed the DCT more. And it had everything to do with getting from point A to point B faster and being pushed back into my seat on each shift. Some have said a short shifter will solve some issues the 6MT has. I can't see it solving a lack of Rpm power band issues that it clearly has.

One last thought... Other than the rpm issue mentioned, the 6MT is running on a stock exhaust and there is something to be said about the overall experience of hearing an exhaust while you are bumping the gears. So in reality, although we know the DCT 2nd gear starting rpm is more desirable, it was also aided by a sweet sounding Gintani X-Pipe.

I welcome any feedback from the manual guys. Certainly not trying to torch my manual brothers.

[94jedi]

Originally Posted by BOOF-M3

Sorry for the delay. Three of us set out today to put your theory to the test. No, not really, we met up and hit some quiet roads this morning. But I did test it out.
Wow, I am stunned by what I saw and felt. First I drove another members E92 6MT. The first two 1st gear redline shifts she would drop to 5,500 in 2nd. Third try I think I hit the redline perfectly and she dropped to 5,750 ish Rpm's.

Then got into my E92 DCT. Before I say where the Rpm's started out in 2nd I must say that the power difference was night and day. You were right, the DCT power felt completely different than the 6MT at the 2nd gear starting point. I hit my first shift manually and I was at 6,700 Rpms when she dropped into 2nd gear. Next try I was about perfect at redline and she dropped to 6,900 when starting 2nd. I then put it in D and floored it and it shifted right at 7,000. So I'm guessing that a perfect redline shift manually should also put her at 7,000.

The difference between starting 2nd at 5,750 and 6,900 is night and day.

All three of us drove the 6MT. As a side note and you had to see this coming if you know me, all three of us said that the DCT was a better driving experience. And that included the owner of the 6MT.

Did I enjoy driving the manual? You bet your sweet A$$ I did. I just enjoyed the DCT more. And it had everything to do with getting from point A to point B faster and being pushed back into my seat on each shift. Some have said a short shifter will solve some issues the 6MT has. I can't see it solving a lack of Rpm power band issues that it clearly has.

One last thought... Other than the rpm issue mentioned, the 6MT is running on a stock exhaust and there is something to be said about the overall experience of hearing an exhaust while you are bumping the gears. So in reality, although we know the DCT 2nd gear starting rpm is more desirable, it was also aided by a sweet sounding Gintani X-Pipe.

I welcome any feedback from the manual guys. Certainly not trying to torch my manual brothers.

no doubt, DCT is going to be the faster car, all else being equal. Personally, I just prefer a manual (F10 shift knob + RE SSK here) at this point in my life. Who knows, maybe in a few years I'll prefer a DCT after daily driving my 6MT in traffic for several years lol.

[EricSMG]

Originally Posted by BOOF-M3

Sorry for the delay. Three of us set out today to put your theory to the test. No, not really, we met up and hit some quiet roads this morning. But I did test it out.
Wow, I am stunned by what I saw and felt. First I drove another members E92 6MT. The first two 1st gear redline shifts she would drop to 5,500 in 2nd. Third try I think I hit the redline perfectly and she dropped to 5,750 ish Rpm's.

Then got into my E92 DCT. Before I say where the Rpm's started out in 2nd I must say that the power difference was night and day. You were right, the DCT power felt completely different than the 6MT at the 2nd gear starting point. I hit my first shift manually and I was at 6,700 Rpms when she dropped into 2nd gear. Next try I was about perfect at redline and she dropped to 6,900 when starting 2nd. I then put it in D and floored it and it shifted right at 7,000. So I'm guessing that a perfect redline shift manually should also put her at 7,000.

The difference between starting 2nd at 5,750 and 6,900 is night and day.

All three of us drove the 6MT. As a side note and you had to see this coming if you know me, all three of us said that the DCT was a better driving experience. And that included the owner of the 6MT.

Did I enjoy driving the manual? You bet your sweet A$$ I did. I just enjoyed the DCT more. And it had everything to do with getting from point A to point B faster and being pushed back into my seat on each shift. Some have said a short shifter will solve some issues the 6MT has. I can't see it solving a lack of Rpm power band issues that it clearly has.

One last thought... Other than the rpm issue mentioned, the 6MT is running on a stock exhaust and there is something to be said about the overall experience of hearing an exhaust while you are bumping the gears. So in reality, although we know the DCT 2nd gear starting rpm is more desirable, it was also aided by a sweet sounding Gintani X-Pipe.

I welcome any feedback from the manual guys. Certainly not trying to torch my manual brothers.

Excellent - the manual drops the revs even more than I recall... which is even worse. The S65 is pretty mellow at 5800rpm and it's fully on the boil at 6900rpm - stomping the throttle at 6900rpm is wicked-bad-ass and stomping it at 5800 is a bit 'meh'.

Wow. I'm sure the DCT redline shifts are WAY more fulfilling do to this. I really want a DCT now - it's just going to be the more thrilling experience when max acceleration is called for. The S65's top end is so thrilling that it makes you crave it and it's very frustrating to drop out of that magical surge when up-shifting in the 6MT. I'm very sensitive to dips in the torque curve and this motor has some big ones that the manual exacerbates.

Ugh. Now, I'm sure an xpipe/tune would do wonders but no matter what, less rpm drop (and MUCH less in this case) will always be considerably better. A shifter has absolutely nothing to do with this - you're right. This is purely about keeping the motor on the boil between shifts. Yes, the faster you can shift means less rpm drop but even a theoretical 'instant' shift cannot mask gear spacing. The 6MT is wide and the DCT is very narrow. This motor needs narrow to work best, plain and simple.

Good thing is, the wife is in love with the E90M 6MT and so maybe I can squeeze a DCT coupe into the mix

Again - don't get me wrong. The manual is awesome in this car. But the spacing is a little wide for the stock S65's powerband.

[MachinesWithSouls]

Welcome back. But I'm not sure why the warning of expensive repair bills. It's an 8 year old M car. Bearings perhaps, but you don't HAVE to do them. I've had mine 8 years and can't say I've spent more than any other performance car I've owned.

Any M car is expensive to upkeep. Unless it's new, in which case it's just expensive to own.

[neilum]

Originally Posted by SoManyBlueCars

Welcome back. But I'm not sure why the warning of expensive repair bills. It's an 8 year old M car. Bearings perhaps, but you don't HAVE to do them. I've had mine 8 years and can't say I've spent more than any other performance car I've owned.

Any M car is expensive to upkeep. Unless it's new, in which case it's just expensive to own.

Looking at the repair history of the car the following has already failed under warranty with the prior owner

- Throttle actuators
- Failed thermostat
- Valve cover gaskets replaced (were leaking)
- 2 ignition coils
- TPM sensors failed

I get the expensive wear items, I am cool with that. Maybe the prior owner got a bit unlucky, but I can't help but think maybe some of that will happen again, its the pessimist in me!

The DCT trans pan is also weaping a little, not a huge deal but it will need to be fixed in the next year or two, plus I may be doing the rod bearings for piece of mind. I'm just thinking realistically that something will break, and even if it doesn't I need to spend about 3k to get it sorted.

[tlow98]

Originally Posted by BOOF-M3

Sorry for the delay. Three of us set out today to put your theory to the test. No, not really, we met up and hit some quiet roads this morning. But I did test it out.
Wow, I am stunned by what I saw and felt. First I drove another members E92 6MT. The first two 1st gear redline shifts she would drop to 5,500 in 2nd. Third try I think I hit the redline perfectly and she dropped to 5,750 ish Rpm's.

Then got into my E92 DCT. Before I say where the Rpm's started out in 2nd I must say that the power difference was night and day. You were right, the DCT power felt completely different than the 6MT at the 2nd gear starting point. I hit my first shift manually and I was at 6,700 Rpms when she dropped into 2nd gear. Next try I was about perfect at redline and she dropped to 6,900 when starting 2nd. I then put it in D and floored it and it shifted right at 7,000. So I'm guessing that a perfect redline shift manually should also put her at 7,000.

The difference between starting 2nd at 5,750 and 6,900 is night and day.

All three of us drove the 6MT. As a side note and you had to see this coming if you know me, all three of us said that the DCT was a better driving experience. And that included the owner of the 6MT.

Did I enjoy driving the manual? You bet your sweet A$$ I did. I just enjoyed the DCT more. And it had everything to do with getting from point A to point B faster and being pushed back into my seat on each shift. Some have said a short shifter will solve some issues the 6MT has. I can't see it solving a lack of Rpm power band issues that it clearly has.

One last thought... Other than the rpm issue mentioned, the 6MT is running on a stock exhaust and there is something to be said about the overall experience of hearing an exhaust while you are bumping the gears. So in reality, although we know the DCT 2nd gear starting rpm is more desirable, it was also aided by a sweet sounding Gintani X-Pipe.

I welcome any feedback from the manual guys. Certainly not trying to torch my manual brothers.

So, the 6MT was stock but the DCT had an x-pipe and cat delete? Did the DCT also have a tune? Pretty big delta in hp with these cars, gear spacing not withstanding.

[BOOF-M3]

Originally Posted by tlow98

So, the 6MT was stock but the DCT had an x-pipe and cat delete? Did the DCT also have a tune? Pretty big delta in hp with these cars, gear spacing not withstanding.

True, would the tune change where the rpms start at in each gear? If so then we need to try with one that has not been tuned. Considering how old these cars are someone must have started an exact thread on this question years ago. I'm texting SohoE93 to see where his rpms start in 2nd. Although he does have a DCT tune but not an ECU so that may still disqualify him or even more so than if he had an ECU tune.

[G80indy]

Nice color combo - - how many miles?

I have the fraternal twin-
Coupe
6 speed

[neilum]

Originally Posted by 330indy

Nice color combo - - how many miles?

I have the fraternal twin-
Coupe
6 speed

Nice! I still have never seen an IB E90 in the flesh outside of mine

Currently sits at 74K miles.

I'll be detailing soon but the weather flat out sucks right now.

[DSilk]

The tune has as much to do with this as anything. While the difference between 5,700 rpm and 6,700 rpms seems like a big deal, it isn't when you are talking about our V8s which hit peak torque at 4,700 rpm. The DCT shifts faster, and has an extra gear, so it will be marginally quicker. But unless you are on a racetrack or a dragstrip that difference isn't material and the question becomes which gearbox is more engaging and enjoyable to drive. For me no paddle shift can replace the joy of manually shifting the gears. I recognize that there are others out there who feel differently, which is why it is great that BMW saw fit to offer both.

[tlow98]

Originally Posted by BOOF-M3

True, would the tune change where the rpms start at in each gear? If so then we need to try with one that has not been tuned. Considering how old these cars are someone must have started an exact thread on this question years ago. I'm texting SohoE93 to see where his rpms start in 2nd. Although he does have a DCT tune but not an ECU so that may still disqualify him or even more so than if he had an ECU tune.

No, tune would not change gear starting points. I'm just trying to point out that if you're comparing gearing then mods make a huge difference in the "feel".

Take a look at the mods and Hp/tq results per rpm. Hope you don't mind me re-posting this, FlipM3!

http://www.m3forum.net/m3forum/showthread.php?t=457232

A stock motor at 5,700 rpms makes 270/240 wheel hp/tq.
A stock motor at 6,900 rpms makes 320/240 wheel hp/tq.

So, already a large delta there, which is to be expected and would account for the feeling of extra pull in second gear when the DCT engages 2nd vs a manual trans engaging 2nd. 50whp delta when stock

A modified (cat and tune) motor at 6,900 rpms makes 350/260 wheel hp/tq. This introduces another 30/20 wheel hp/tq over the stock motor.

I'm just pointing out that you're comparing cars that are making a delta of 80whp/20wtq - a sizeable margin of which is based on modifications and mostly bc wheel power is gearing based but it's confounded as you are not including speed. Of course, there will be a large objective difference in fee.

This does not reflect reality in that speed based comparisons are more appropriate. Put both cars at a similar speed to see the real difference in acceleration over time. If you take away a large margin of the DCT's advantage (the launch) you will see that rolling tests reveal the acceleration to be mostly the same. This is because the manual gets a longer period of access to the high hp section of the powerband through its longer gearing. This is using cars of similar tune.

It's all trade-offs

Now, subjectively, the feel and use-case are all up to the user/buyer. I can totally understand sound reasoning for either case.

Cheers for a nice discussion, as always.

[BOOF-M3]

Originally Posted by tlow98

No, tune would not change gear starting points. I'm just trying to point out that if you're comparing gearing then mods make a huge difference in the "feel".

Take a look at the mods and Hp/tq results per rpm. Hope you don't mind me re-posting this, FlipM3!

http://www.m3forum.net/m3forum/showthread.php?t=457232

A stock motor at 5,700 rpms makes 270/240 wheel hp/tq.
A stock motor at 6,900 rpms makes 320/240 wheel hp/tq.

So, already a large delta there, which is to be expected and would account for the feeling of extra pull in second gear when the DCT engages 2nd vs a manual trans engaging 2nd. 50whp delta when stock

A modified (cat and tune) motor at 6,900 rpms makes 350/260 wheel hp/tq. This introduces another 30/20 wheel hp/tq over the stock motor.

I'm just pointing out that you're comparing cars that are making a delta of 80whp/20wtq - a sizeable margin of which is based on modifications and mostly bc wheel power is gearing based but it's confounded as you are not including speed. Of course, there will be a large objective difference in fee.

This does not reflect reality in that speed based comparisons are more appropriate. Put both cars at a similar speed to see the real difference in acceleration over time. If you take away a large margin of the DCT's advantage (the launch) you will see that rolling tests reveal the acceleration to be mostly the same. This is because the manual gets a longer period of access to the high hp section of the powerband through its longer gearing. This is using cars of similar tune.

It's all trade-offs

Now, subjectively, the feel and use-case are all up to the user/buyer. I can totally understand sound reasoning for either case.

Cheers for a nice discussion, as always.

You sir are a poet. A couple of points: on an earlier occasion my tuned E93 carrying 350+ extra lbs beat the non tuned 6MT from rolling starts, from speeds of 50+ and go, 60+ and go and over 70+ and go. The 6MT was defeated every time. It is quite possible that said 6MT driver selected the wrong gear each and every time.

6MT E92 driver then drove one of the non tuned E93's with DCT and said it felt faster than his car. They however did not race.

[BOOF-M3]

Originally Posted by DSilk

The tune has as much to do with this as anything. While the difference between 5,700 rpm and 6,700 rpms seems like a big deal, it isn't when you are talking about our V8s which hit peak torque at 4,700 rpm. The DCT shifts faster, and has an extra gear, so it will be marginally quicker. But unless you are on a racetrack or a dragstrip that difference isn't material and the question becomes which gearbox is more engaging and enjoyable to drive. For me no paddle shift can replace the joy of manually shifting the gears. I recognize that there are others out there who feel differently, which is why it is great that BMW saw fit to offer both.

I have never used the paddle shifts, I only shift with the center console shifter. But I agree with your point. Also, which vehicle is faster is irrelevant to me and to most owners I think. What is relevant is what we as a driver find more engaging. What we are learning is why one is faster is all and commenting on it. I personally am not trying to rub anyone's nose in anything. I own an E93 so I have no business telling others what is good for them.

[SLC Steve]

Are you me? Complete with DCT and premium sound? Good to see you!

[neilum]

Originally Posted by SLC Steve

Are you me? Complete with DCT and premium sound? Good to see you!

Hey... Nice car!!

Too funny, almost exact spec.

[EricSMG]

Originally Posted by DSilk

The tune has as much to do with this as anything. While the difference between 5,700 rpm and 6,700 rpms seems like a big deal, it isn't when you are talking about our V8s which hit peak torque at 4,700 rpm. The DCT shifts faster, and has an extra gear, so it will be marginally quicker. But unless you are on a racetrack or a dragstrip that difference isn't material and the question becomes which gearbox is more engaging and enjoyable to drive. For me no paddle shift can replace the joy of manually shifting the gears. I recognize that there are others out there who feel differently, which is why it is great that BMW saw fit to offer both.

Peak stock torque is much lower at 3900 rpm - just look at any dyno. The difference between 5700 and 6700 is HUGE in these cars. It's a completely different motor at those two rpms - just getting going vs full on balls to the wall. I guess you don't redline it much.

Also - while the DCT has technically 'one' more gear, there's more to it in reality. Consider that 7th is 1:1 while the 6MT's 5th is 1:1.

This means that it actually has two more gears crammed into that same range. This is what accounts for the much smaller rpm drop between gears.

Originally Posted by tlow98

No, tune would not change gear starting points. I'm just trying to point out that if you're comparing gearing then mods make a huge difference in the "feel".

Take a look at the mods and Hp/tq results per rpm. Hope you don't mind me re-posting this, FlipM3!

A stock motor at 5,700 rpms makes 270/240 wheel hp/tq.
A stock motor at 6,900 rpms makes 320/240 wheel hp/tq.

So, already a large delta there, which is to be expected and would account for the feeling of extra pull in second gear when the DCT engages 2nd vs a manual trans engaging 2nd. 50whp delta when stock

A modified (cat and tune) motor at 6,900 rpms makes 350/260 wheel hp/tq. This introduces another 30/20 wheel hp/tq over the stock motor.

I'm just pointing out that you're comparing cars that are making a delta of 80whp/20wtq - a sizeable margin of which is based on modifications and mostly bc wheel power is gearing based but it's confounded as you are not including speed. Of course, there will be a large objective difference in fee.

This does not reflect reality in that speed based comparisons are more appropriate. Put both cars at a similar speed to see the real difference in acceleration over time. If you take away a large margin of the DCT's advantage (the launch) you will see that rolling tests reveal the acceleration to be mostly the same. This is because the manual gets a longer period of access to the high hp section of the powerband through its longer gearing. This is using cars of similar tune.

It's all trade-offs

Now, subjectively, the feel and use-case are all up to the user/buyer. I can totally understand sound reasoning for either case.

Cheers for a nice discussion, as always.

Excellent post! I always appreciate well though out responses like this.

I agree with everything you noted, but two additional points:

- See my comment above about the DCT's gear spacing, and
- While you are absolutely correct about the change in 'absolute' power making a dramatic difference in feel (I've drooled over Flip's dyno numerous times), the slope of the torque curve as you roll back on the throttle also places a big role in 'feel'.

The stock powerband of the S65 has two big dips: the worst on starts at 4k and ends in the low 5k range (if you smash the throttle in this range the car actually feels kinda slow) and another slightly smaller dip between 5.5k and about 6.5k.

So - starting 2nd gear at 5700rpm has you heading into a dip while starting second gear at 6900 has you on an incline. This may seem sublte but it really affects the feel of the motor. This is why turbo cars feel sleepy up top (super steep downward tq slope) even though they're still making good horsepower.

However - it seems that choice modifications can reduce or even remove these dips and so, absolute power aside, the feel should be much much more "alive".

Finally - to your point about gearing, the DCT's 2nd gear will be numerically higher which means a slower road speed - so yes, it will feel faster at a given rpm but will be forced to 3rd sooner, thus giving up a small amount of it's advantage for that particular gear. The only caveat here is that the DCT has a WAY taller ring and pinion and so, without doing the actual math on final gearing per gear for both the DCT and manual, I'm not sure how much actual road speed (or road force, for that matter) delta exists gear for gear between them.

I DO know that the manual is quite tall - it will do high 60s in second and nearly 110mph topped out in 3rd. That's a little too tall to be usable with such a narrow upper powerband. I crave for that high rpm rush but it's virtually unobtainable on the street, above 2nd gear, save for very specific situations - it's just too fast. Assuming that the DCT's 2nd and 3rd ratios are shorter, this likely means that topping out third is a little more approachable and thus, fun.

Good stuff!

[tlow98]

Originally Posted by EricSMG

Peak stock torque is much lower at 3900 rpm - just look at any dyno. The difference between 5700 and 6700 is HUGE in these cars. It's a completely different motor at those two rpms - just getting going vs full on balls to the wall. I guess you don't redline it much.

Also - while the DCT has technically 'one' more gear, there's more to it in reality. Consider that 7th is 1:1 while the 6MT's 5th is 1:1.

This means that it actually has two more gears crammed into that same range. This is what accounts for the much smaller rpm drop between gears.



Excellent post! I always appreciate well though out responses like this.

I agree with everything you noted, but two additional points:

- See my comment above about the DCT's gear spacing, and
- While you are absolutely correct about the change in 'absolute' power making a dramatic difference in feel (I've drooled over Flip's dyno numerous times), the slope of the torque curve as you roll back on the throttle also places a big role in 'feel'.

The stock powerband of the S65 has two big dips: the worst on starts at 4k and ends in the low 5k range (if you smash the throttle in this range the car actually feels kinda slow) and another slightly smaller dip between 5.5k and about 6.5k.

So - starting 2nd gear at 5700rpm has you heading into a dip while starting second gear at 6900 has you on an incline. This may seem sublte but it really affects the feel of the motor. This is why turbo cars feel sleepy up top (super steep downward tq slope) even though they're still making good horsepower.

However - it seems that choice modifications can reduce or even remove these dips and so, absolute power aside, the feel should be much much more "alive".

Finally - to your point about gearing, the DCT's 2nd gear will be numerically higher which means a slower road speed - so yes, it will feel faster at a given rpm but will be forced to 3rd sooner, thus giving up a small amount of it's advantage for that particular gear. The only caveat here is that the DCT has a WAY taller ring and pinion and so, without doing the actual math on final gearing per gear for both the DCT and manual, I'm not sure how much actual road speed (or road force, for that matter) delta exists gear for gear between them.

I DO know that the manual is quite tall - it will do high 60s in second and nearly 110mph topped out in 3rd. That's a little too tall to be usable with such a narrow upper powerband. I crave for that high rpm rush but it's virtually unobtainable on the street, above 2nd gear, save for very specific situations - it's just too fast. Assuming that the DCT's 2nd and 3rd ratios are shorter, this likely means that topping out third is a little more approachable and thus, fun.

Good stuff!

Very good points and I absolutely agree, especially with the fact that the stock 6MT is simply a bit tall for (optimizing max fun-factor) usable road conditions in the US. Really, quite a shame!

I felt a similar feeling with a friends AP1 S2000 - I wanted more access to the top end without having to go so fast. To a lesser degree, I felt the same way with my CSL intake'd/tuned E46 M3 as I felt the low-end torque was a bit suffering after those modifications. Stock, however, the throttle response down low is amazing.

It's my thought that these shortcomings in the real world are often thanks to modern manufacturers optimizing for different markets (autobahn use) and they love to chase magazine number contests.

I've actually not driven a DCT S65, but thinking critically about this makes me think I might actually prefer it. Who doesn't want to have access to that ripping top end more? And as you mentioned, there's 2 extra gears there, which is huge. Regarding the speed and rear end ratio...yeah, it looks like the DCT really only starts to separate itself from the 6MT with 3rd and 4th gear, which is a bit of a shame - as that's pretty high speed, too.

There's a lot of talk about lower rear ends in the DCT, but not a lot of facts. Bummer! It seems in the real world, a slightly saner (3.45ish?) rear end in the DCT would be utterly exhilarating in the real world on US roads.

A DCT E90 does sound quite lovely.

Also, nice pick up with your car! Looks like a minty example and I always appreciate your thoughts on this stuffs.

[thkfast]

ITB - Individual Throttle Bodies

I had to Google that one.

This was the most respectful thread I've ever read!

And that's all I have to say about that.

[spazzyfry123]

Excellent spec! Welcome to the E90.

Originally Posted by BOOF-M3

Sorry for the delay. Three of us set out today to put your theory to the test. No, not really, we met up and hit some quiet roads this morning. But I did test it out.
Wow, I am stunned by what I saw and felt. First I drove another members E92 6MT. The first two 1st gear redline shifts she would drop to 5,500 in 2nd. Third try I think I hit the redline perfectly and she dropped to 5,750 ish Rpm's.

Then got into my E92 DCT. Before I say where the Rpm's started out in 2nd I must say that the power difference was night and day. You were right, the DCT power felt completely different than the 6MT at the 2nd gear starting point. I hit my first shift manually and I was at 6,700 Rpms when she dropped into 2nd gear. Next try I was about perfect at redline and she dropped to 6,900 when starting 2nd. I then put it in D and floored it and it shifted right at 7,000. So I'm guessing that a perfect redline shift manually should also put her at 7,000.

The difference between starting 2nd at 5,750 and 6,900 is night and day.

All three of us drove the 6MT. As a side note and you had to see this coming if you know me, all three of us said that the DCT was a better driving experience. And that included the owner of the 6MT.

Did I enjoy driving the manual? You bet your sweet A$$ I did. I just enjoyed the DCT more. And it had everything to do with getting from point A to point B faster and being pushed back into my seat on each shift. Some have said a short shifter will solve some issues the 6MT has. I can't see it solving a lack of Rpm power band issues that it clearly has.

One last thought... Other than the rpm issue mentioned, the 6MT is running on a stock exhaust and there is something to be said about the overall experience of hearing an exhaust while you are bumping the gears. So in reality, although we know the DCT 2nd gear starting rpm is more desirable, it was also aided by a sweet sounding Gintani X-Pipe.

I welcome any feedback from the manual guys. Certainly not trying to torch my manual brothers.

You can take my keys this fall, Mark. I also notice the large gap while shifting full steam, but the screamer of exhaust I have still keeps it the visceral experience (especially with all four windows down and a hard surface like a bridge or tunnel for the sound to bounce from). The involvement and satisfaction of those rare perfect shifts is what keeps me going on the third pedal. I've said it a thousand times since I got the car, though: wish I would have gotten the DCT sometimes.