Shifting in "D" or "S" -- a comparison.
04-30-2011, 11:14 AM
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Shifting in "D" or "S" -- a comparison.
Hi Folks,
I've been driving entirely in "D" (Drive) since I bought my 2009 C6. Now that I'm close to the 36k warranty I've been trying certain things out to make sure they work. Most recently, I've been trying the car out in Sport shifting mode. Couple of questions/comments...
Does the system "rev" the engine a bit to match engine speed to a downshift in the S mode? In D mode the transmission seems to downshift well after the fact (as brakes are applied and one is slowing down) so engine revs are kept low. But as I downshift in S mode there seems to be a bit of an artifical "revving" of the engine to bring it up to the proper matching RPM. Is this actually something built into the system? Or is there something wrong with my tranny in S mode? (I'm pretty sure it working fine, so just double-checking)
I notice this same "revving" or almost "double-clutching" feature in the E-Geared Lamborghinis, such as the Murcielago and Gallardo. They try to match a manual shift action/sound as the car decelerates.
Is this going on in the Vette as well? Fwiw, I find it annoying and would just like the car to shift without all the "fuss" in-between gears. Just a soft/quick "bang" for the downshifts -- not a "rev up" or even (in the case of the Lambos) the racey "double-clutch." I don't want to show off for all the girls, I just want the frickin' thing to downshift.
Hope I'm making myself clear on this one. I mainly want to verify that the car does rev the motor a bit on downshift in S mode. (which is what it's doing)
Thanks!
Fred
I've been driving entirely in "D" (Drive) since I bought my 2009 C6. Now that I'm close to the 36k warranty I've been trying certain things out to make sure they work. Most recently, I've been trying the car out in Sport shifting mode. Couple of questions/comments...
Does the system "rev" the engine a bit to match engine speed to a downshift in the S mode? In D mode the transmission seems to downshift well after the fact (as brakes are applied and one is slowing down) so engine revs are kept low. But as I downshift in S mode there seems to be a bit of an artifical "revving" of the engine to bring it up to the proper matching RPM. Is this actually something built into the system? Or is there something wrong with my tranny in S mode? (I'm pretty sure it working fine, so just double-checking)
I notice this same "revving" or almost "double-clutching" feature in the E-Geared Lamborghinis, such as the Murcielago and Gallardo. They try to match a manual shift action/sound as the car decelerates.
Is this going on in the Vette as well? Fwiw, I find it annoying and would just like the car to shift without all the "fuss" in-between gears. Just a soft/quick "bang" for the downshifts -- not a "rev up" or even (in the case of the Lambos) the racey "double-clutch." I don't want to show off for all the girls, I just want the frickin' thing to downshift.
Hope I'm making myself clear on this one. I mainly want to verify that the car does rev the motor a bit on downshift in S mode. (which is what it's doing)
Thanks!
Fred
04-30-2011, 11:29 AM
#2
Team Owner
The '08+ A6's rev match on downshifting when using the paddles. My '08 doesn't rev match when just driving around in "S" mode, not using the paddles.
04-30-2011, 11:52 AM
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I'll give that a shot, thanks!
Fred
PS: I have so far approached this car as basically a family sedan where I just drive it around to pick up groceries. ie: I'm just starting to learn what it can do.
04-30-2011, 12:00 PM
#4
Team Owner
Just know that there is no difference in D and S modes. Driving in S mode just means you have the paddle function available if you want/need it. 
04-30-2011, 12:26 PM
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I just want to make sure that's not something I need the dealer to look at.
Thanks,
Fred
04-30-2011, 02:50 PM
#6
That is not true according to the owners manual. The manual states that "While in S (Sport Mode), the transmission will have more noticeable upshifts for sportier vehicle performance". Once you touch the paddle shifters in the "s" mode, that turns it into a paddle function mode.
04-30-2011, 03:10 PM
#7
Drifting
And yes the S mode without touching the paddles does shift differently--higher rpms....thus a bit more perforamnce but at the cost of mpg.
There is also a wee bit of lag on upshifts with the paddles...but you can learn to anticipate it and shfit accordingly. You can also have it "tuned" for a more instant paddle response at the price of your warranty (which may not be an issue for you).
In either D or S the car will start off in 2nd gear (again mpg). If you use the paddles you can stop, downshift to first and then start in 1st if you so desire for a bit more pick up....
04-30-2011, 03:12 PM
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Ok, that's what I need to explore. (I mean, besides the owner's manual -- hehe)
So there are 3 ways to shift this car:
1 - Leave it in D
2 - Leave it in S
3 - Leave it in S and used the paddles
# 2 was the one I was unaware of, my bad
I'm going to play around with that one today. With 34,700 miles on the car I want to make sure everything's working properly.
Thanks so much!
Fred
So there are 3 ways to shift this car:
1 - Leave it in D
2 - Leave it in S
3 - Leave it in S and used the paddles
# 2 was the one I was unaware of, my bad
I'm going to play around with that one today. With 34,700 miles on the car I want to make sure everything's working properly.
Thanks so much!
Fred
04-30-2011, 03:23 PM
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St. Jude Donor '13
YES! When downshifting with the paddles it WILL REV MATCH. That is intentional and built into the system. In the auto Vette world it is considered one of the "cooler" features of the A6.
And yes the S mode without touching the paddles does shift differently--higher rpms....thus a bit more perforamnce but at the cost of mpg.
There is also a wee bit of lag on upshifts with the paddles...but you can learn to anticipate it and shfit accordingly. You can also have it "tuned" for a more instant paddle response at the price of your warranty (which may not be an issue for you).
In either D or S the car will start off in 2nd gear (again mpg). If you use the paddles you can stop, downshift to first and then start in 1st if you so desire for a bit more pick up....
And yes the S mode without touching the paddles does shift differently--higher rpms....thus a bit more perforamnce but at the cost of mpg.
There is also a wee bit of lag on upshifts with the paddles...but you can learn to anticipate it and shfit accordingly. You can also have it "tuned" for a more instant paddle response at the price of your warranty (which may not be an issue for you).
In either D or S the car will start off in 2nd gear (again mpg). If you use the paddles you can stop, downshift to first and then start in 1st if you so desire for a bit more pick up....
In D, the car always starts in 1st.
In S, the car starts in 1st if you haven't been using the paddles.
If you are in S and using the paddles, the tranny will downshift only to 2nd as you come to a stop. It will then start in 2nd and stay there until you paddle up to 3rd, or until you go back to D.
Under gentle acceleration, the 1-2 shift is so soft and comes so soon; many people think the car started in 2nd.
04-30-2011, 03:25 PM
#10
Team Owner
All correct except that last part:
In D, the car always starts in 1st.
In S, the car starts in 1st if you haven't been using the paddles.
If you are in S and using the paddles, the tranny will downshift only to 2nd as you come to a stop. It will then start in 2nd and stay there until you paddle up to 3rd, or until you go back to D.
Under gentle acceleration, the 1-2 shift is so soft and comes so soon; many people think the car started in 2nd.
In D, the car always starts in 1st.
In S, the car starts in 1st if you haven't been using the paddles.
If you are in S and using the paddles, the tranny will downshift only to 2nd as you come to a stop. It will then start in 2nd and stay there until you paddle up to 3rd, or until you go back to D.
Under gentle acceleration, the 1-2 shift is so soft and comes so soon; many people think the car started in 2nd.
04-30-2011, 03:31 PM
#11
Drifting
04-30-2011, 03:31 PM
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YES! When downshifting with the paddles it WILL REV MATCH. That is intentional and built into the system. In the auto Vette world it is considered one of the "cooler" features of the A6.
And yes the S mode without touching the paddles does shift differently--higher rpms....thus a bit more perforamnce but at the cost of mpg.
There is also a wee bit of lag on upshifts with the paddles...but you can learn to anticipate it and shfit accordingly. You can also have it "tuned" for a more instant paddle response at the price of your warranty (which may not be an issue for you).
In either D or S the car will start off in 2nd gear (again mpg). If you use the paddles you can stop, downshift to first and then start in 1st if you so desire for a bit more pick up....
And yes the S mode without touching the paddles does shift differently--higher rpms....thus a bit more perforamnce but at the cost of mpg.
There is also a wee bit of lag on upshifts with the paddles...but you can learn to anticipate it and shfit accordingly. You can also have it "tuned" for a more instant paddle response at the price of your warranty (which may not be an issue for you).
In either D or S the car will start off in 2nd gear (again mpg). If you use the paddles you can stop, downshift to first and then start in 1st if you so desire for a bit more pick up....
I noticed the "wee bit of lag" on upshifts -- and am glad you mentioned it...must be normal.
Didn't know about the possibility of getting the paddle response tuned under warranty, thanks for that, good to know! My feeling at this point is, anything I can get done before 36k miles I'm going to ask for. I'm assuming it's all built into the price of the car anyway.
Good info here -- thanks everybody!
Fred
04-30-2011, 03:33 PM
#13
Burning Brakes
That is not true according to the owners manual. The manual states that "While in S (Sport Mode), the transmission will have more noticeable upshifts for sportier vehicle performance". Once you touch the paddle shifters in the "s" mode, that turns it into a paddle function mode.
04-30-2011, 03:34 PM
#14
Drifting
Excellent, thanks.
I noticed the "wee bit of lag" on upshifts -- and am glad you mentioned it...must be normal.
Didn't know about the possibility of getting the paddle response tuned under warranty, thanks for that, good to know! My feeling at this point is, anything I can get done before 36k miles I'm going to ask for. I'm assuming it's all built into the price of the car anyway.
Good info here -- thanks everybody!
Fred
I noticed the "wee bit of lag" on upshifts -- and am glad you mentioned it...must be normal.
Didn't know about the possibility of getting the paddle response tuned under warranty, thanks for that, good to know! My feeling at this point is, anything I can get done before 36k miles I'm going to ask for. I'm assuming it's all built into the price of the car anyway.
Good info here -- thanks everybody!
Fred
yes the upshift lag is normal but can be anticipated--hit the button a few hudrend rpms before the intended upshift poiint...
04-30-2011, 03:35 PM
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D,s,p
I cannot believe that you have been driving your Vette all this time & totally unaware of the transmission you have......did you not test drive a Vette before purchasing ? ! Have you not read your oweners manual ? !
You are now going to find out what a super vehicle you own. Welcome to Vette owenership......ENJOY THE RIDE !!!!!!!
You are now going to find out what a super vehicle you own. Welcome to Vette owenership......ENJOY THE RIDE !!!!!!!
04-30-2011, 03:51 PM
#16
Team Owner
That is not true according to the owners manual. The manual states that "While in S (Sport Mode), the transmission will have more noticeable upshifts for sportier vehicle performance". Once you touch the paddle shifters in the "s" mode, that turns it into a paddle function mode.
The people that wrote the owner's manual didn't confer with the people that programmed the trans. There is no difference in the shift tables for D and S, as it comes from the factory.Sorry for the long response, but I have learned a lot with my new HP Tuner that I would like to share.
I would agree that the manual does say that it holds gears longer in S mode, but I don't think it is any different than D. The stock shift tables for D and S are exactly the same for every gear. Meaning it does not hold any gear longer in S mode. I'm not referring to the shift firmness, just the shift speeds based on throttle position. The table below is the stock shift tables for 1st - 4th gears. The top table below is D (Normal), the bottom table is S (Performance). The shift speeds are identical for 1st - 6th gears on upshifts and downshifts. (5th and 6th tables are separate). I have modified my S tables to do what the manual says it does. Mine will hold gears longer and downshift earlier in S mode. It makes a huge difference by not allowing the car to bog down by early shifting.
For example, notice that 1st gear will shift at 8 MPH with not much throttle and kind of bogs or hesitates as it hits 2nd gear. I changed the first three boxes to 12, 14, and 16 (along with most of the boxes). Now in S mode the car will not shift until 12 MPH and the harder the throttle the longer it will hold 1st. To keep it in gear that long with stock tables you had to be giving it 25% to 37% throttle. I left D stock and they are now truely Normal vs. Performance modes.
These examples are Part Throttle, the same thing holds true for Full Throttle. The Full Throttle tables are exactly the same too. There are also RPM vs. Throttle tables and both D and S are identical shifting at 6400, 6400, and 6300 in 1st, 2nd, and 3rd respectively.
I would agree that the manual does say that it holds gears longer in S mode, but I don't think it is any different than D. The stock shift tables for D and S are exactly the same for every gear. Meaning it does not hold any gear longer in S mode. I'm not referring to the shift firmness, just the shift speeds based on throttle position. The table below is the stock shift tables for 1st - 4th gears. The top table below is D (Normal), the bottom table is S (Performance). The shift speeds are identical for 1st - 6th gears on upshifts and downshifts. (5th and 6th tables are separate). I have modified my S tables to do what the manual says it does. Mine will hold gears longer and downshift earlier in S mode. It makes a huge difference by not allowing the car to bog down by early shifting.
For example, notice that 1st gear will shift at 8 MPH with not much throttle and kind of bogs or hesitates as it hits 2nd gear. I changed the first three boxes to 12, 14, and 16 (along with most of the boxes). Now in S mode the car will not shift until 12 MPH and the harder the throttle the longer it will hold 1st. To keep it in gear that long with stock tables you had to be giving it 25% to 37% throttle. I left D stock and they are now truely Normal vs. Performance modes.
These examples are Part Throttle, the same thing holds true for Full Throttle. The Full Throttle tables are exactly the same too. There are also RPM vs. Throttle tables and both D and S are identical shifting at 6400, 6400, and 6300 in 1st, 2nd, and 3rd respectively.
04-30-2011, 04:12 PM
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So others are saying they feel a difference? (I need to test for myself)
Fred
04-30-2011, 04:15 PM
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I cannot believe that you have been driving your Vette all this time & totally unaware of the transmission you have......did you not test drive a Vette before purchasing ? ! Have you not read your oweners manual ? !
You are now going to find out what a super vehicle you own. Welcome to Vette owenership......ENJOY THE RIDE !!!!!!!
You are now going to find out what a super vehicle you own. Welcome to Vette owenership......ENJOY THE RIDE !!!!!!!
I rented a Hertz Vette, drove it across country, liked it, and bought it. Didn't even open the hood. (seriously)
It's a great car, you can feel that the second you get it in and start driving. Can't beat it for the money.
Fred
04-30-2011, 05:59 PM
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