Shorshifting for faster acceleration

[Danielegov]

I've heard someone say that shifting at 5500rpm is the best in the stinger at 3 and 4th gear because the torque drops after 5500rpm so by short-shifting you can go faster. I looked around the internet and didn't see a single person talk or even mention this. Has anyone heard anything like that before? Would be cool to know you can make the car go faster by knowing a secret way to drive it. I'm not claiming anything here I just wanted to hear other opinions about this maybe someone out here knows something that a lot of us don't and would like to share.

 

[oddball]

In a real drag scenario you want to shift at peak HP, and gear the car such that the engine lands just at or above peak torque after the shift.

Other quirks such as the specific gearing, tire compound, track situation, weather conditions, etc, will impact how a driver makes the pass. The guys that are chasing hundredths of a second to get to 10's are paying attention to this stuff. The gear spread between different gears may slightly change the best shift point, but you're waaaaaay down into the details.

Torque always drops off sooner or later. That's fine. HP is what matters once the revs are up.

Frankly, for this car and what you're likely doing with it, you just have to find what works for your driving style, your reaction time, your roads and tires, etc etc. Catching the shift before smacking into the rev limiter is the most important bit.

 

[MerlintheMad]

Yes, to not banging off the rev limiter. And a normal dig from a green light is a shift from 1st to 2nd, and from 2nd to 3rd, right about where OP said: c. 5.5K RPM. If you leave it later than that, while the trans is shifting up, the needle bounces up to between 6 and 6.5K RPM. I have had it happen numerous times: I'll be shifting myself (99% I use paddle shifters) and leave it a tad too late and before I can pull the paddle, the car takes over and upshifts for me. Heh. So, I pull the paddle at c. 5 to 5.5K RPM. Once you're into 4th gear space between shifts is a lot slower (i.e. is closer to my reaction time ).

By the way, my favorite gear is 4th gear: you can get it at c. 20 MPH and carry it over 100 MPH to red line; and torque the entire range is incredible. That doesn't mean I drive around in 4th gear: but I do find it the most facile way to divide my attention between car and driving: I know that 4th will stand in for any passing or maneuvering situation (as I said, I use paddles virtually all the time).

 

[65RivieraGS]

I've used the Launch Mode on my Stinger and I think that the AT program in Sport Mode is fine. Trying to "fine tune your shifts in so-called "manual mode" and shifting with the paddles is fun, but not nearly as reliable as using the AT. That's one benefit of a dual-clutch AT like on my 135is .... shifting was always perfect and never a soft spot. Plus when Launch mode was engaged, it really did outperform the regular sport mode..



Drive it like you stole it!!! We got 10/100 --- don't be afraid!

 

[Danielegov]

I've used the Launch Mode on my Stinger and I think that the AT program in Sport Mode is fine. Trying to "fine tune your shifts in so-called "manual mode" and shifting with the paddles is fun, but not nearly as reliable as using the AT. That's one benefit of a dual-clutch AT like on my 135is .... shifting was always perfect and never a soft spot. Plus when Launch mode was engaged, it really did outperform the regular sport mode..



Drive it like you stole it!!! We got 10/100 --- don't be afraid!

Wait is the G70 and stinger a Dual Clutch? when i just punch the pedal without in auto the needle hits redline and cause me to slow down so paddle shifters is more reliable for me when I race or what not.

 

[G-569253]

Wait is the G70 and stinger a Dual Clutch? when i just punch the pedal without in auto the needle hits redline and cause me to slow down so paddle shifters is more reliable for me when I race or what not.

it is not

 

[Jayphil]

The Stinger / G70 is a regular auto, not a dual clutch. Also usually on stock cars the shift point in sport should be programmed for best acceleration. When you modify, especially a turbo, car the optimal power band usually is moved lower in the RPM but the car shift points are unchanged and this is where you often benefit from shifting sooner or short shifting.

 

[65RivieraGS]

Wait is the G70 and stinger a Dual Clutch? when i just punch the pedal without in auto the needle hits redline and cause me to slow down so paddle shifters is more reliable for me when I race or what not.

NO!!! My note was not so clear. The KIA/Hyundai 8speeds ARE NOT dual clutch. My 2013 BMW 135is was a DCT. My point was that the BMW DCT was flawless and fast .... faster than using the paddles on the steering wheel. My 2006 M3 had a SMG gearbox with selectable modes ... amazing technology!! Of course, my current employer, Siemens, designed the controllers for this happy stuff.

 

[AWDGT2]

At some point during your tuning process you will have to paddle shift at the track, I don't think you are there yet. Terry does a good job creating Maps that don't push the car and the ECU so far that the throttle closes down on you. Once you get bored of Meth and Map7, you WILL have to paddle the car down the track, trust me.
If you have a JB, you can clearly see boost drop significantly after 5k. The goal is to keep that boost flat between 5.5k and 5.8K. I've attached a perfect example of an automatic shift and what happens to the boost. Also, notice the orange line drop hard at the 1-2 shift, that is the throttle closing. This was an aggressive Map7 and shows what we are stuck with when it comes to pushing the limits. If this run was done manual shifting, the RPM line would not go above 6k, the boost wouldn't drop as much, and that throttle wouldn't of closed. It probably cost a 1/10 or maybe 2/10th.

 

[runner1]

On map2 I get throttle close 1-2 and sometimes 2-3. If I paddle shift 1-2 would I need to 2-3 shift? or is there a way after 1-2 shift for the trans to take over again. Or if not at what rpm should I hit the paddle for best upshift?

 

[Pearly]

On map2 I get throttle close 1-2 and sometimes 2-3. If I paddle shift 1-2 would I need to 2-3 shift? or is there a way after 1-2 shift for the trans to take over again. Or if not at what rpm should I hit the paddle for best upshift?

I know this is a older post but did you ever get a proper response to this question?

 

[runner1]

Sold the car. But the answer was partially cold weather related and secondly short shifting is recommended. There are recommendations for where to shift each gear on the n54 forums

 

[StingertimeNC]

short shift! if under full throttle shift at 5.8-5.9k so the shift is actually completed around 6k. Boost tapers above that. If you were to short shift say 1-2 and 2-3, and you are in sport mode, you would need to hold the right paddle down to go back in to auto mode, or do it manually however a GT1 or GT requires.