M3 6speed vs DCT

[Ken37.73]

DCT is sh1t - there I said it !

[lincoln]

Where can you run to the limiter like that multiple times... I'm envious. Our roads in the greater puget sound area are flooded with cops, rocks, lights, and cars...

[hungltc.imaging]

I chose R-Tronic for my R8 because I live in Hong Kong. LOL!

[naveenb]

i am going to say this with my flame suit on. i test drove a m-dct and a 6 speed manual. i have driven many different types of cars also. i think at the end of the day it really comes down to preference. i would prefer driving a manual but i have to say the manual in bmw m3 is not as smooth as other cars. also, haven't the newer auto transmissions become more fuel effiecient and much faster at actually shifting gears than manuals?

[dcstep]

Originally Posted by naveenb

i am going to say this with my flame suit on. i test drove a m-dct and a 6 speed manual. i have driven many different types of cars also. i think at the end of the day it really comes down to preference. i would prefer driving a manual but i have to say the manual in bmw m3 is not as smooth as other cars. also, haven't the newer auto transmissions become more fuel effiecient and much faster at actually shifting gears than manuals?

Why would that get you flames?

I love both also, but own the 6MT. At the Performance Center and VIR I use BMW's DCTs quite happily (they don't have any 6MTs due to driver limits and/or political reasons). I picked the 6MT partly because it'll mainly be street and autocross (lots of 2d gear and little shifting). For drag and track I might have gone with the DCT. On the street I perfer the certainty of the 6MT and never having to look at a display to know which gear I'm in, or constantly counting gears. If I weren't so experienced with the 6MT, being a habitual double clutcher and heel and toe guy.

Dave

[mixja]

In theory, the shorter gearing and tighter ratios the DCT has from 3rd to 6th gears should make it quicker up top. The tighter spread of the gears means a DCT car will be operating more around peak HP than the MT so it SHOULD be faster...

I've driven both cars - the DCT only for a test drive, the MT for almost two months now...

When I drove the DCT and MT back to back, the DCT definitely felt the quicker car. Whether or not it actually is I can't say, but the most important thing to me as the driver is how the car feels. And the DCT without a doubt felt quicker.

IMO the MT is actually pretty boring, it's lack of torque and taller gearing is annoying for daily driving and on the highway once you're into fourth gear you are going way too fast for where I live. I find that it is difficult to really accelerate away from other cars that I would expect to easily beat - the M3 MT always seems to win but it is never convincing (examples - one car was a 2.0L Turbo Subaru Legacy rated at around 280HP but probably modified and the other was an older Holden aka Pontiac R8 rated at around 370HP).

At least the DCT has shorter gearing from 3rd gear onwards, which makes daily driving that much easier. Coming out of an RS4, I'd have to say I'd take the RS4 over the MT, but the DCT takes the M3 to a level above the RS4.

Anyway, I'll get my E90 DCT soon, I've had an E90 MT for a couple of months now and certainly hope the DCT will make me happier.

[dcstep]

Originally Posted by mixja

IMO the MT is actually pretty boring, it's lack of torque and taller gearing is annoying for daily driving and on the highway once you're into fourth gear you are going way too fast for where I live. I find that it is difficult to really accelerate away from other cars that I would expect to easily beat - the M3 MT always seems to win but it is never convincing (examples - one car was a 2.0L Turbo Subaru Legacy rated at around 280HP but probably modified and the other was an older Holden aka Pontiac R8 rated at around 370HP).

Since the car cruise in 6th above 3,000 I generally drive around town in the 3 to 4000 range, at least when there's a chance of a run. Depending on the competition I might make certain that I'm over 4-grand. When you look at the dyno run torque curves you'll see this broad range from just below 4,000 rpm to 8400 where the torque hardly varies. Between 3 and 4000 grand the torque is ok, but beloww 3 it's right there with a Mazda rotary or Honda S2000.

The car is meant to run in this rpm range, so I'd suggest using it. When I drove a Mustang, 2500 was half the useable rpm range and 1000 after the torque had kicked in. The M3 is an entirely different animal. I find it pretty thrilling at 4-grand and above.

Dave

[mixja]

Originally Posted by dcstep

Since the car cruise in 6th above 3,000 I generally drive around town in the 3 to 4000 range, at least when there's a chance of a run. Depending on the competition I might make certain that I'm over 4-grand. When you look at the dyno run torque curves you'll see this broad range from just below 4,000 rpm to 8400 where the torque hardly varies. Between 3 and 4000 grand the torque is ok, but beloww 3 it's right there with a Mazda rotary or Honda S2000.

The car is meant to run in this rpm range, so I'd suggest using it. When I drove a Mustang, 2500 was half the useable rpm range and 1000 after the torque had kicked in. The M3 is an entirely different animal. I find it pretty thrilling at 4-grand and above.

Dave

Yeah it is thrilling above 4000RPM but when you step into a DCT and experience +4000RPM in the higher gears (3rd gear especially) the MT loses its appeal somewhat.

I found the same experience with the manual transmission - gearbox feels pretty good to me now after having a loaner MT for a couple of months, but six months ago when I stepped straight from my RS4 into a MT for a test drive, I found the manual transmission markedly inferior to the RS4 transmission...

I think there is nothing really between the DCT and MT in terms of performance numbers, it's the driver experience that is most important, and that's where I feel the DCT has it over the MT.

On the street where you have to watch your speed, you're really limited to 1st, 2nd and 3rd in the MT - 4000RPM in 4th gear in the MT is 67MPH vs 51MPH in the DCT...

[dcstep]

Originally Posted by mixja

On the street where you have to watch your speed, you're really limited to 1st, 2nd and 3rd in the MT - 4000RPM in 4th gear in the MT is 67MPH vs 51MPH in the DCT...

Yeah, so? Really, I dont understand the issue. I just drive in 3d, if there's a chance that I might "get into it." 4th is a highway acceleration gear. Why would I worry about what gear the DCT would be in? Around town, I'll get into 4th, 5th and even 6th at 45 mph and the car doesn't complain, it just won't be fast.

Like I said, I picked the 6MT as the more suitable for autocross. I've already got decades of double-clutching and heel and toe, so that wasnt an issue. Still, for most drivers I'd probably recommend the DCT, particularly if they might do lap days and/or drag instead of autocross. For full time street, it's hard to beat because anyone can drive the DCT and, at the worst, you lose no performance and many (most?) people will gain performance.

Dave

[mixja]

Originally Posted by dcstep

Yeah, so? Really, I dont understand the issue. I just drive in 3d, if there's a chance that I might "get into it." 4th is a highway acceleration gear. Why would I worry about what gear the DCT would be in? Around town, I'll get into 4th, 5th and even 6th at 45 mph and the car doesn't complain, it just won't be fast.

Like I said, I picked the 6MT as the more suitable for autocross. I've already got decades of double-clutching and heel and toe, so that wasnt an issue. Still, for most drivers I'd probably recommend the DCT, particularly if they might do lap days and/or drag instead of autocross. For full time street, it's hard to beat because anyone can drive the DCT and, at the worst, you lose no performance and many (most?) people will gain performance.

Dave

Reminds me of the old 5 speed vs 6 speed debate - and I'm guessing it probably happened way back when for 4 speed vs 5 speed...

[naveenb]

Originally Posted by dcstep

Why would that get you flames?

I love both also, but own the 6MT. At the Performance Center and VIR I use BMW's DCTs quite happily (they don't have any 6MTs due to driver limits and/or political reasons). I picked the 6MT partly because it'll mainly be street and autocross (lots of 2d gear and little shifting). For drag and track I might have gone with the DCT. On the street I perfer the certainty of the 6MT and never having to look at a display to know which gear I'm in, or constantly counting gears. If I weren't so experienced with the 6MT, being a habitual double clutcher and heel and toe guy.

Dave

after reading your post, i think that m dct might be the way i go because of traffic in socal. i do love manual, but i will not get to rip up the car that often and i will be sitting in traffic more often than sitting on a track with the car.

[naveenb]

Originally Posted by mixja

Yeah it is thrilling above 4000RPM but when you step into a DCT and experience +4000RPM in the higher gears (3rd gear especially) the MT loses its appeal somewhat.

I found the same experience with the manual transmission - gearbox feels pretty good to me now after having a loaner MT for a couple of months, but six months ago when I stepped straight from my RS4 into a MT for a test drive, I found the manual transmission markedly inferior to the RS4 transmission...

I think there is nothing really between the DCT and MT in terms of performance numbers, it's the driver experience that is most important, and that's where I feel the DCT has it over the MT.

On the street where you have to watch your speed, you're really limited to 1st, 2nd and 3rd in the MT - 4000RPM in 4th gear in the MT is 67MPH vs 51MPH in the DCT...

bmw manual transmissions are very hard and heavy for some strange reason.

[MrHarris]

I do feel the gears are a bit long, besides first, for the 6speed m3.

[///Monster]

This is a pretty interesting story considering all the data given by bmw and other sources states DCT is faster

[Heat00]

arent they both great?

[dcstep]

Originally Posted by Heat00

arent they both great?

Exactly.

[ruff]

I thought the BMW doting C&D cleared this up.

[mixja]

Check out my comparison here http://www.m3post.com/forums/showpos...0&postcount=39 - once the M3 MT shifts into 3rd gear, in theory the DCT will leave it for dead, pulling out to around a 4 car length lead by 250km/h (from a 20km/h rolling start in 1st gear)...

[Cyclenirvana]

I love 6MTs. My wife and I have 2: Honda S2000 and Ford GT...and they could not be more different. The Ford GT has so much low RPM torque that you never find yourself lacking for power or in the wrong gear. The Honda S2000 is a blast, but I find it tiring to drive in traffic or long distances. It has a redline of 9K. You don't really get into its power band until your past 5K! Driving the new BMW M3 reminds somewhat of the latter. I find it hard to extract the power out of such cars with high redlines and a 6MT unless I am driving "hard" at the track. To me, these types of cars are where DCT and F1 transmissions really seem to work well if not better, especially off the track. Ferraris and Lambos also have V8 and V10 with astronomical redlines, and, at least for me, it is easier to extract and enjoy their power on public roads with the automated manual transmissions. I seem to be able to keep the revs consistently high, shifts are smoother, and, as someone pointed out, the car "feels" faster. Having said all that, if I did not own another 6MT, I would have ordered one in the M3. But I think the DCT is the better fit overall for the M3.

[Robin_NL]

Originally Posted by Cyclenirvana

I love 6MTs. My wife and I have 2: Honda S2000 and Ford GT...and they could not be more different.

Any pics of the Ford GT perhaps?

[Cyclenirvana]

Originally Posted by Robin Hood

Any pics of the Ford GT perhaps?

Here you go...at VIR.

[Robin_NL]

Fantastic! Thanx man