Comparing the M5's SMG with M3's DCT
#21
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Originally Posted by Filip535D' post='805675' date='Mar 2 2009, 06:01 PM
Hi,
My wife has a M3 DCT and i have a M5 SMG.
The difference
M5 - 1 clutch - 1 transmission with 7 gears
M3 - 2 clutches - 2 transmissions with Left ( 1-3-5-7) and right ( 2-4-6)
When you shift in the M5, the gear has to be taken like with a manual transmission, 1 by 1.
With the M3 , every next gear is waiting to come in , so when you are driving in Second gear and you pull the paddle, the next gear immediatly is there without any delay, it's like with a scooter with a vario, the kick and sensation is much less with the M3 then with the M5. This because you don't have the bang that shakes your head by shifting ( hope this is understandable).
The only good difference for me is , when you do a kickdown in 7th gear with the M3 , you give 1 pull on the paddle and the gearbox is going to the best gear immediatly. With the M5 you have to pull several times to go 3 gears down.
I hope this gives an idea of the difference.
Greetings
Filip
My wife has a M3 DCT and i have a M5 SMG.
The difference
M5 - 1 clutch - 1 transmission with 7 gears
M3 - 2 clutches - 2 transmissions with Left ( 1-3-5-7) and right ( 2-4-6)
When you shift in the M5, the gear has to be taken like with a manual transmission, 1 by 1.
With the M3 , every next gear is waiting to come in , so when you are driving in Second gear and you pull the paddle, the next gear immediatly is there without any delay, it's like with a scooter with a vario, the kick and sensation is much less with the M3 then with the M5. This because you don't have the bang that shakes your head by shifting ( hope this is understandable).
The only good difference for me is , when you do a kickdown in 7th gear with the M3 , you give 1 pull on the paddle and the gearbox is going to the best gear immediatly. With the M5 you have to pull several times to go 3 gears down.
I hope this gives an idea of the difference.
Greetings
Filip
#22
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SMG - Sequential Manual Gear
The paddle shifts one-gear per one-click at a time - sequentially.
If you are in 7th, click down 3 times then you are in 4th.
In D-mode, if you are coasting at 7th and then floor it, it will shift directly to 5th or 3rd depending on speed. Not sequential anymore. The SMG III logic is 7-5-3-1 and 6-4-2.
The clutch release can be smoothed out by backing off on the gas during shift.
Just like when you drive the manual tranmission, you let off the gas when you clutch-in, shift gear and then back on the gas again.
If you stay on the gas and paddle shift, the action will be jerky at low speed/low gear (<40mph , 1-2) but is fun and quick at high spped/high gear.
The paddle shifts one-gear per one-click at a time - sequentially.
If you are in 7th, click down 3 times then you are in 4th.
In D-mode, if you are coasting at 7th and then floor it, it will shift directly to 5th or 3rd depending on speed. Not sequential anymore. The SMG III logic is 7-5-3-1 and 6-4-2.
The clutch release can be smoothed out by backing off on the gas during shift.
Just like when you drive the manual tranmission, you let off the gas when you clutch-in, shift gear and then back on the gas again.
If you stay on the gas and paddle shift, the action will be jerky at low speed/low gear (<40mph , 1-2) but is fun and quick at high spped/high gear.
#24
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Originally Posted by S2000' post='843523' date='Apr 10 2009, 03:04 PM
SMG - Sequential Manual Gear
The paddle shifts one-gear per one-click at a time - sequentially.
If you are in 7th, click down 3 times then you are in 4th.
In D-mode, if you are coasting at 7th and then floor it, it will shift directly to 5th or 3rd depending on speed. Not sequential anymore. The SMG III logic is 7-5-3-1 and 6-4-2.
The clutch release can be smoothed out by backing off on the gas during shift.
Just like when you drive the manual tranmission, you let off the gas when you clutch-in, shift gear and then back on the gas again.
If you stay on the gas and paddle shift, the action will be jerky at low speed/low gear (<40mph , 1-2) but is fun and quick at high spped/high gear.
The paddle shifts one-gear per one-click at a time - sequentially.
If you are in 7th, click down 3 times then you are in 4th.
In D-mode, if you are coasting at 7th and then floor it, it will shift directly to 5th or 3rd depending on speed. Not sequential anymore. The SMG III logic is 7-5-3-1 and 6-4-2.
The clutch release can be smoothed out by backing off on the gas during shift.
Just like when you drive the manual tranmission, you let off the gas when you clutch-in, shift gear and then back on the gas again.
If you stay on the gas and paddle shift, the action will be jerky at low speed/low gear (<40mph , 1-2) but is fun and quick at high spped/high gear.
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Originally Posted by firegabe' post='843715' date='Apr 10 2009, 10:33 PM
My '06 M5 SMG dose not shift as quickly as I had hoped. My dads Ferrari 360 F1 shifts MUCH quicker! and nicer
what drivelogic settings are you using? it should be faster than the ole 360 at this point
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Originally Posted by m630' post='856407' date='Apr 23 2009, 06:13 PM
what drivelogic settings are you using? it should be faster than the ole 360 at this point
and back to the topic, now the question begs to be asked:
Is the M3 DCT faster than the SMG III? In the most aggressive mode!
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Here is BMW bulletin (I have driven neither so am not qualified other than providing this bulletin)
SI B 28 07 08
M Double-clutch Transmission with Drivelogic January 2009
Technical Service
SUBJECT
M3 with M DCT - Complaint of Delayed Throttle Response
MODEL
E90, E92, E93 with S65 and M DCT transmission
SITUATION
The customer may complain about delayed throttle response when reaccelerating after a series of downshifts during heavy deceleration (hard braking). This condition is experienced when the transmission is in D or S mode, with the Drivelogic program selected to three or less bars.
No acceleration delay is experienced when the vehicle is driven in the M manual mode.
INFORMATION
During a "rolling stop" situation, which is followed by heavy acceleration demand, the transmission goes through the series of downshifts in order to match the appropriate gear with the high load signal.
The short time period necessary to perform the multiple downshifts may create the perception of "throttle delay". In reality, it is a design characteristic and normal behavior for the M DCT transmission, rather then a malfunction or deficiency.
Do not attempt any repair (software update or hardware replacement) for this type of complaint.
Explain the M DCT's operating behavior, as described above, to the customer.
It is interesting to note, however, that the new X5/6 Ms come with an modified STEP. THis is probably due more to the massive torque these monsters have, but..... It may also be that the REAL Ms will have too much torque also for a DCT, but one never knows what will transpire by then.
SI B 28 07 08
M Double-clutch Transmission with Drivelogic January 2009
Technical Service
SUBJECT
M3 with M DCT - Complaint of Delayed Throttle Response
MODEL
E90, E92, E93 with S65 and M DCT transmission
SITUATION
The customer may complain about delayed throttle response when reaccelerating after a series of downshifts during heavy deceleration (hard braking). This condition is experienced when the transmission is in D or S mode, with the Drivelogic program selected to three or less bars.
No acceleration delay is experienced when the vehicle is driven in the M manual mode.
INFORMATION
During a "rolling stop" situation, which is followed by heavy acceleration demand, the transmission goes through the series of downshifts in order to match the appropriate gear with the high load signal.
The short time period necessary to perform the multiple downshifts may create the perception of "throttle delay". In reality, it is a design characteristic and normal behavior for the M DCT transmission, rather then a malfunction or deficiency.
Do not attempt any repair (software update or hardware replacement) for this type of complaint.
Explain the M DCT's operating behavior, as described above, to the customer.
It is interesting to note, however, that the new X5/6 Ms come with an modified STEP. THis is probably due more to the massive torque these monsters have, but..... It may also be that the REAL Ms will have too much torque also for a DCT, but one never knows what will transpire by then.
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Originally Posted by cobradav' post='856651' date='Apr 23 2009, 09:36 PM
Here is BMW bulletin (I have driven neither so am not qualified other than providing this bulletin)
SI B 28 07 08
M Double-clutch Transmission with Drivelogic January 2009
Technical Service
SUBJECT
M3 with M DCT - Complaint of Delayed Throttle Response
MODEL
E90, E92, E93 with S65 and M DCT transmission
SITUATION
The customer may complain about delayed throttle response when reaccelerating after a series of downshifts during heavy deceleration (hard braking). This condition is experienced when the transmission is in D or S mode, with the Drivelogic program selected to three or less bars.
No acceleration delay is experienced when the vehicle is driven in the M manual mode.
INFORMATION
During a "rolling stop" situation, which is followed by heavy acceleration demand, the transmission goes through the series of downshifts in order to match the appropriate gear with the high load signal.
The short time period necessary to perform the multiple downshifts may create the perception of "throttle delay". In reality, it is a design characteristic and normal behavior for the M DCT transmission, rather then a malfunction or deficiency.
Do not attempt any repair (software update or hardware replacement) for this type of complaint.
Explain the M DCT's operating behavior, as described above, to the customer.
It is interesting to note, however, that the new X5/6 Ms come with an modified STEP. THis is probably due more to the massive torque these monsters have, but..... It may also be that the REAL Ms will have too much torque also for a DCT, but one never knows what will transpire by then.
SI B 28 07 08
M Double-clutch Transmission with Drivelogic January 2009
Technical Service
SUBJECT
M3 with M DCT - Complaint of Delayed Throttle Response
MODEL
E90, E92, E93 with S65 and M DCT transmission
SITUATION
The customer may complain about delayed throttle response when reaccelerating after a series of downshifts during heavy deceleration (hard braking). This condition is experienced when the transmission is in D or S mode, with the Drivelogic program selected to three or less bars.
No acceleration delay is experienced when the vehicle is driven in the M manual mode.
INFORMATION
During a "rolling stop" situation, which is followed by heavy acceleration demand, the transmission goes through the series of downshifts in order to match the appropriate gear with the high load signal.
The short time period necessary to perform the multiple downshifts may create the perception of "throttle delay". In reality, it is a design characteristic and normal behavior for the M DCT transmission, rather then a malfunction or deficiency.
Do not attempt any repair (software update or hardware replacement) for this type of complaint.
Explain the M DCT's operating behavior, as described above, to the customer.
It is interesting to note, however, that the new X5/6 Ms come with an modified STEP. THis is probably due more to the massive torque these monsters have, but..... It may also be that the REAL Ms will have too much torque also for a DCT, but one never knows what will transpire by then.
Anyway in SMG JJJ i don't think this should be a problem as per that SB. Still i'm wondering which is faster?
#29
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"M5 - 1 clutch - 1 transmission with 7 gears
M3 - 2 clutches - 2 transmissions with Left ( 1-3-5-7) and right ( 2-4-6)"
actually this is not quite correct. i just had my m5 transmission rebuilt and found 2 clutch plates. i think it is more of the number of transmissions - 1 versus 2.
M3 - 2 clutches - 2 transmissions with Left ( 1-3-5-7) and right ( 2-4-6)"
actually this is not quite correct. i just had my m5 transmission rebuilt and found 2 clutch plates. i think it is more of the number of transmissions - 1 versus 2.
#30
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[quote name='lawguy' timestamp='1235834717' post='803871']
Its an interesting question, for sure. I'm not trying to start a rivalry or war, just to really hear more from the SMG crowd what they think.
I think the M3 is a wonderful car too. Its just a bit small for a 40-something guy with 3 kids and a pair of chubby law partners that have to ride with me from time to time...LOL.
[/quote
yikes - I'd have to say that the M3 IS too small for you (from reading the above) - also, you do know that BMW stopped offering the 4 door - so you'd have to get "used"
p.s.: I drive an '08 M5 w/SMG and absolutely love it - spirited driving with both hands on the wheel while up/down shifting on hairpin roads is never having to say you're sorry..
Its an interesting question, for sure. I'm not trying to start a rivalry or war, just to really hear more from the SMG crowd what they think.
I think the M3 is a wonderful car too. Its just a bit small for a 40-something guy with 3 kids and a pair of chubby law partners that have to ride with me from time to time...LOL.
[/quote
yikes - I'd have to say that the M3 IS too small for you (from reading the above) - also, you do know that BMW stopped offering the 4 door - so you'd have to get "used"
p.s.: I drive an '08 M5 w/SMG and absolutely love it - spirited driving with both hands on the wheel while up/down shifting on hairpin roads is never having to say you're sorry..