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      11-13-2018, 10:32 AM   #1
O Haiii
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DCT question: automatic DCT upshift when you keep bouncing off the rev limiter ?

Hi guys,

I am about to pull the trigger and from my M2 testdrives, i have come to accept the fact that the 6mt in the M2 is just not at the level of Miata, S2000, Civic type R, etc. The flywheel is way too heavy, shifter is clunky, and makes the car feel heavier than it is.

So, i am leaning towards getting a DCT. In manual mode, will the dct up shift automatically if you keep bouncing off the rev limiter? I would like full control of the gears and i would like the dct to not shift even if i keep bouncing off the limiter. Thanks in advance!
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      11-13-2018, 10:34 AM   #2
Anthony1s
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Quote:
Originally Posted by O Haiii View Post
Hi guys,

I am about to pull the trigger and from my M2 testdrives, i have come to accept the fact that the 6mt in the M2 is just not at the level of Miata, S2000, Civic type R, etc. The flywheel is way too heavy, shifter is clunky, and makes the car feel heavier than it is.

So, i am leaning towards getting a DCT. In manual mode, will the dct up shift automatically if you keep bouncing off the rev limiter? I would like full control of the gears and i would like the dct to not shift even if i keep bouncing off the limiter. Thanks in advance!
Correct, it won't upshift.
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      11-13-2018, 12:28 PM   #3
ShelJW
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As Anthony said, in manual mode, with DCT, you're completely on your own, other then one situation... (that I know of)

If you push petal to the floor, and then downshift, the car will find the lowest acceptable gear, and shift into that gear.

Say you're in 5th, and you floor it and downshift... car will find which gear it can downshift into and still stay below red line, and put the car into that gear instantly, for instant pick-up.
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      11-13-2018, 12:46 PM   #4
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Quote:
Originally Posted by ShelJW View Post
As Anthony said, in manual mode, with DCT, you're completely on your own, other then one situation... (that I know of)

If you push petal to the floor, and then downshift, the car will find the lowest acceptable gear, and shift into that gear.

Say you're in 5th, and you floor it and downshift... car will find which gear it can downshift into and still stay below red line, and put the car into that gear instantly, for instant pick-up.
One correction, if my understanding is correct. It won't downshift multiple gears"instantly". Well, I mean it won't do it as fast as normal DCT shifts.

The reason for this is how DCT gearboxes work. They are basically two manual gearboxes in one. One for the odd gears and one for the even gears. The car predicts what gear you will most likely want next and pre-engages it in the idle gearbox. So say you're in 2nd and you have your foot on the gas, the car will engage 3rd gear in the idle box because that's the one you're mostly likely to choose next (because you're foot is on the gas). But say you take your foot off the gas or stop on the brake, the car will engage 1st gear in the idle gearbox because it assumes you want to downshift based on the action of braking or letting off the gas. That's how DCT gearboxes achieve fast gear changes.

I'm unaware of a way to precalculate that you want to dropdown multiple gears, so it still has to manually engage the gear you want instead of having it pre-loaded based on your actions. So, in this circumstance, it will engage the gear at the same speed that a normal transmission will.
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      11-14-2018, 12:35 AM   #5
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Quote:
Originally Posted by Anthony1s View Post
One correction, if my understanding is correct. It won't downshift multiple gears"instantly". Well, I mean it won't do it as fast as normal DCT shifts.

The reason for this is how DCT gearboxes work. They are basically two manual gearboxes in one. One for the odd gears and one for the even gears. The car predicts what gear you will most likely want next and pre-engages it in the idle gearbox. So say you're in 2nd and you have your foot on the gas, the car will engage 3rd gear in the idle box because that's the one you're mostly likely to choose next (because you're foot is on the gas). But say you take your foot off the gas or stop on the brake, the car will engage 1st gear in the idle gearbox because it assumes you want to downshift based on the action of braking or letting off the gas. That's how DCT gearboxes achieve fast gear changes.

I'm unaware of a way to precalculate that you want to dropdown multiple gears, so it still has to manually engage the gear you want instead of having it pre-loaded based on your actions. So, in this circumstance, it will engage the gear at the same speed that a normal transmission will.
I think you describe pretty well how the DCT works but I don't believe it is likely to preselect 1st unless your speed is decreasing at a fairly high rate and most likely that your foot is on the brake because the computer is looking at more than just your throttle position to predict the gear set preselection. What I is being discussed above is say your in 6th gear and want to accelerate aggressively, you can pull the downshift lever and hold it for a second and it will select the lowest possible gear for you. Of course when your'e in manual mode you can bounce against the rev limiter quickly so it's not something you want to do without paying close attention.
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      11-14-2018, 01:43 AM   #6
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Quote:
Originally Posted by pruettfan View Post
Quote:
Originally Posted by Anthony1s View Post
One correction, if my understanding is correct. It won't downshift multiple gears"instantly". Well, I mean it won't do it as fast as normal DCT shifts.

The reason for this is how DCT gearboxes work. They are basically two manual gearboxes in one. One for the odd gears and one for the even gears. The car predicts what gear you will most likely want next and pre-engages it in the idle gearbox. So say you're in 2nd and you have your foot on the gas, the car will engage 3rd gear in the idle box because that's the one you're mostly likely to choose next (because you're foot is on the gas). But say you take your foot off the gas or stop on the brake, the car will engage 1st gear in the idle gearbox because it assumes you want to downshift based on the action of braking or letting off the gas. That's how DCT gearboxes achieve fast gear changes.

I'm unaware of a way to precalculate that you want to dropdown multiple gears, so it still has to manually engage the gear you want instead of having it pre-loaded based on your actions. So, in this circumstance, it will engage the gear at the same speed that a normal transmission will.
I think you describe pretty well how the DCT works but I don't believe it is likely to preselect 1st unless your speed is decreasing at a fairly high rate and most likely that your foot is on the brake because the computer is looking at more than just your throttle position to predict the gear set preselection. What I is being discussed above is say your in 6th gear and want to accelerate aggressively, you can pull the downshift lever and hold it for a second and it will select the lowest possible gear for you. Of course when your'e in manual mode you can bounce against the rev limiter quickly so it's not something you want to do without paying close attention.
I don't think holding it does anything. you can double tap quickly, or hit the kick down switch while down shifting. Both will skip gears, but with kick down and down shift it skips to the lowest safe gear.
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      11-14-2018, 09:50 AM   #7
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Quote:
Originally Posted by akkando View Post
I don't think holding it does anything. you can double tap quickly, or hit the kick down switch while down shifting. Both will skip gears, but with kick down and down shift it skips to the lowest safe gear.
No, holding it doesn't. But in automatic mode it will drop down a bunch of gears when you floor it in a high gear. I believe it keeps the same gear if you do it in manual mode. But that's nothing revolutionary. My 2007 Saab 93 does the same thing.
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      11-14-2018, 12:33 PM   #8
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IMO the manual transmission while not up to Porsche standards is still amongst the best available today. A properly working Civic Type R transmission is great but only if you have a good one as plenty are very notchy going into 2nd gear and plenty suffer from grinding and lockout in the higher gears. There’s also nothing wrong with the flywheel as the rev-hang is programmed in for emissions like most new cars using manual transmissions in this day and age. In regards to the S2000 and Miata it’s easy to make a slick manual transmission when it only has to be built to handle the torque of an economy car engine.
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      11-14-2018, 01:07 PM   #9
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Quote:
Originally Posted by heavyD^2 View Post
IMO the manual transmission while not up to Porsche standards is still amongst the best available today. A properly working Civic Type R transmission is great but only if you have a good one as plenty are very notchy going into 2nd gear and plenty suffer from grinding and lockout in the higher gears. There’s also nothing wrong with the flywheel as the rev-hang is programmed in for emissions like most new cars using manual transmissions in this day and age. In regards to the S2000 and Miata it’s easy to make a slick manual transmission when it only has to be built to handle the torque of an economy car engine.
I'd also ask the OP...have you had a chance to drive an M2 with some miles on it? My 6MT has been sweet from day 1, smooth with no issues, but about 2 weeks ago at around 3500 miles it went from really nice to "wow" nice. I don't know whether it's temperature change, or break-in (do manual transmissions break in??), or placebo or just me eating more veggies but the manual in my M2 is smooth as butter. Maybe I just got lucky, but if everyone on the fence were to experience how smooth my 6MT is they'd go manual every time.
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      11-28-2018, 12:17 AM   #10
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Quote:
Originally Posted by afwares View Post
I'd also ask the OP...have you had a chance to drive an M2 with some miles on it? My 6MT has been sweet from day 1, smooth with no issues, but about 2 weeks ago at around 3500 miles it went from really nice to "wow" nice. I don't know whether it's temperature change, or break-in (do manual transmissions break in??), or placebo or just me eating more veggies but the manual in my M2 is smooth as butter. Maybe I just got lucky, but if everyone on the fence were to experience how smooth my 6MT is they'd go manual every time.
Hey! I got the car on Thanksgiving weekend! MSRP was 60950 and i got it for 57750 out the door including 10% california tax and fees. So i think i got around 15% discount. Gotta love the M2C coming out and demolishing the OG M2 prices!

While i do like the 6mt in the m2, im coming from an s2000 and a miata, which are the pinnacle of manual transmission benchmarking. I felt the 6mt in the m2 actually made the car feel heavier and more disconnected. I got the dct and it's the best transmission ive ever owned so far. How it bangs into the gears during aggressive upshift is the best thing ive ever felt. Feels like a supercar. I'm sure the 6mt is great for most folks tho and regardless of the transmission this car is AWESOME!!!
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      11-28-2018, 07:52 AM   #11
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Quote:
Originally Posted by O Haiii View Post
Hey! I got the car on Thanksgiving weekend! MSRP was 60950 and i got it for 57750 out the door including 10% california tax and fees. So i think i got around 15% discount. Gotta love the M2C coming out and demolishing the OG M2 prices!

While i do like the 6mt in the m2, im coming from an s2000 and a miata, which are the pinnacle of manual transmission benchmarking. I felt the 6mt in the m2 actually made the car feel heavier and more disconnected. I got the dct and it's the best transmission ive ever owned so far. How it bangs into the gears during aggressive upshift is the best thing ive ever felt. Feels like a supercar. I'm sure the 6mt is great for most folks tho and regardless of the transmission this car is AWESOME!!!
Congratulations. I agree with you about the DCT. I love having it.
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      11-28-2018, 08:01 AM   #12
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Originally Posted by DanG View Post
Congratulations. I agree with you about the DCT. I love having it.
I read 'I love hating it'

But this is my 2nd DCT //M car and I love it--->N55/S55+DCT+LSD=King (imho)

Cheers
Robin
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      11-28-2018, 08:52 AM   #13
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I read 'I love hating it'
So did I - and I thought well, this is bimmerpost!
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