I'm sure all you auto tranny guys know what I'm talking about. You floor the throttle, but there is a hesitation before it take off, or at a stand still you foot brake and try to get your revs up and I can't get them past like 2000 rpms which really kills the take off. Once your going the car pulls very nicely, but that first few moments is very lagging. I know this has to do with the torque mgmt. What I want to know is how to get rid of it. I know a tune can help, but on the 08's which have a Bosch controller on the tranny there is no tuning for the transmission. Will an ecm tune alone help with this hesitation. Thanks for your help.
I'm sure all you auto tranny guys know what I'm talking about. You floor the throttle, but there is a hesitation before it take off, or at a stand still you foot brake and try to get your revs up and I can't get them past like 2000 rpms which really kills the take off. Once your going the car pulls very nicely, but that first few moments is very lagging. I know this has to do with the torque mgmt. What I want to know is how to get rid of it. I know a tune can help, but on the 08's which have a Bosch controller on the tranny there is no tuning for the transmission. Will an ecm tune alone help with this hesitation. Thanks for your help.
Do you have the traction control selection button on your dash? I'm not sure but it may help a bit by turning it off or to competition mode.
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DEEP, GT CONCEPT KIT,RK SPORT RAM AIR HOOD, RAZZI WING, UP-SHIELD, EIBACH SPRINGS(1.7”R), DEJON CAI AND I/C PIPES, CUSTOM EXHAUST,CUSTOM PAINT AND GRAPHICS, RMR STYLE BAR, LED AND ACCENT LIGHTS, CUSTOM GAUGE FACE, DASHHAWK UNIT,Premium package w/leather, A/C, Auto, 18" chrome wheels, 6-disc audio w/monsoon 7, spoiler, sport pedals.
Only other thing I could think of to try then is instead of holding the brake pedal and gasing try the e-brake and gas. Brake pedal may be triggering the RPM limiter module like it does when in Park or neutral. unless you have been in those gears trying to pop start your take off's. I don't think you are though case the park and neu. limit is set at 4k RPM.
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DEEP, GT CONCEPT KIT,RK SPORT RAM AIR HOOD, RAZZI WING, UP-SHIELD, EIBACH SPRINGS(1.7”R), DEJON CAI AND I/C PIPES, CUSTOM EXHAUST,CUSTOM PAINT AND GRAPHICS, RMR STYLE BAR, LED AND ACCENT LIGHTS, CUSTOM GAUGE FACE, DASHHAWK UNIT,Premium package w/leather, A/C, Auto, 18" chrome wheels, 6-disc audio w/monsoon 7, spoiler, sport pedals.
There are a few -limited- features that can be adjusted in the ECU to partly address this, but the bottom line is that it requires the reprogram of the TCU to take care of it. The problem is that no tuning software is available for the TCU for any year kappa at this time.
One thing that can help a little in the ECU is the rpm acceleration rate and possibly bumping up the neutral and park rev limit from 4000 to 5000.
If you notice under no load and a slow throttle up to rpm it will go all the way to 4000 and stop, but if you slam it you'll find it hit an almost random limiter anywhere from 2000 to 3000.
There is Map called Rev Limiter Accel Modifier that lowers the Rev Limiter values by the amount defined in the table corresponding to the acceleration rate of the engine RPM.
Moving that can help with rpm ramp rate, but the transmission will still take its time locking up the torque converter clutch, which makes the car feel like nothing is happening.
However this requires a tune and a less expensive solution would be to use the PRNDL selector as an almost manual stick and put it in I mode when you want quick shifts and aggressive response from the transmission. I shift the heck out of my automatic and feel that it offers 90% of the performance I expect, you just have to remember to slam it into I if you want to fast pass someone or pull out into traffic.
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-Adam Chant
SCdyne Performance Engineering "Tune it or lose it!
There are a few -limited- features that can be adjusted in the ECU to partly address this, but the bottom line is that it requires the reprogram of the TCU to take care of it. The problem is that no tuning software is available for the TCU for any year kappa at this time.
One thing that can help a little in the ECU is the rpm acceleration rate and possibly bumping up the neutral and park rev limit from 4000 to 5000.
If you notice under no load and a slow throttle up to rpm it will go all the way to 4000 and stop, but if you slam it you'll find it hit an almost random limiter anywhere from 2000 to 3000.
There is Map called Rev Limiter Accel Modifier that lowers the Rev Limiter values by the amount defined in the table corresponding to the acceleration rate of the engine RPM.
Moving that can help with rpm ramp rate, but the transmission will still take its time locking up the torque converter clutch, which makes the car feel like nothing is happening.
However this requires a tune and a less expensive solution would be to use the PRNDL selector as an almost manual stick and put it in I mode when you want quick shifts and aggressive response from the transmission. I shift the heck out of my automatic and feel that it offers 90% of the performance I expect, you just have to remember to slam it into I if you want to fast pass someone or pull out into traffic.
This is some very good info. Thanks! So there is no tuning anywhere for the Kappa auto
tranny? Is there anything coming down the pike? I'm not trying to build a drag car, but
it would be nice to stomp on the throttle from a dead stop and have it fire out of the hole.
It just needs to get some torque to the ground instantly. I would say if I could get the revs up with the brake on up to about 5000 or so
I could launch dam good.
Also have the automatic with the Westers tune, huge diference in performance after the tune, much quicker response but no where near the improvement on the manual. This is from 6 of us, two autos and 4 manuals all with same westers tune dynoing our cars on the same day with the same dyno. About 40 to 50 hp diference to the rear wheels.
I wrote to lyndon wester and he is aware of the situation and will be working on it. Problem he says is with the torque converter.
The tune is still worth it as the improvement is dramatic but I hate that the manuals with the tune can kick my butt.
Will be going to the track for 1/4 mile test against manual with same tune and same other mods. Stay tuned for the results.
Quick trick...select "I" on the auto and try again. You should notice some improvement...but it's definitely a trade off for having the auto.
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Team Solstice 2008 HOT SHOT Aggressive 2007 GXP Auto-minus On*Star, spoiler, and smokers pkg. Delivered December 4, 2006
Ave mixed driving 26 mpg
2 failed pinion seals...300+ miles, and 9,700+ miles...and one more under recall at 12,636 miles for a grand total of 3!
Driver's outside door handle came apart in May 2008...repaired June 2008
Canvas top replaced June 2008.
Gas cap replaced.
All repairs covered under warranty.
Also have the automatic with the Westers tune, huge diference in performance after the tune, much quicker response but no where near the improvement on the manual. This is from 6 of us, two autos and 4 manuals all with same westers tune dynoing our cars on the same day with the same dyno. About 40 to 50 hp diference to the rear wheels.
I wrote to lyndon wester and he is aware of the situation and will be working on it. Problem he says is with the torque converter.
The tune is still worth it as the improvement is dramatic but I hate that the manuals with the tune can kick my butt.
Will be going to the track for 1/4 mile test against manual with same tune and same other mods. Stay tuned for the results.
Chuck
Awesome. I can't wait to see your results. Don't for get to report back.
Also have the automatic with the Westers tune, huge diference in performance after the tune, much quicker response but no where near the improvement on the manual. This is from 6 of us, two autos and 4 manuals all with same westers tune dynoing our cars on the same day with the same dyno. About 40 to 50 hp diference to the rear wheels.
I wrote to lyndon wester and he is aware of the situation and will be working on it. Problem he says is with the torque converter.
The tune is still worth it as the improvement is dramatic but I hate that the manuals with the tune can kick my butt.
Will be going to the track for 1/4 mile test against manual with same tune and same other mods. Stay tuned for the results.
Chuck
You guys going to Capital? Let me know and I will join you. They open around 4-5pm for test and tune every Friday night. don't forget your helmet.
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BIX A BEL Cool, Ebony leather, Chrome, loaded, no XM/onstar Founding member of the "Lost Sols Club"
Deposit (1100) - 9/29/05, 1101/1102 - 2 Feb 06, 2500 - 7 Feb 06, 3000 - 8 Feb 06, 3100 - 13 Feb 06, 3300 - 13 Feb 06, 3400 - 14 Feb 06, 3800 - 24 Feb 06 (112544), 4000 - 24 Feb 06, 4150 - 24 Feb 06
dealer expected deliver 6 March, arrived 28 Feb, picked up that night w 3.2 miles on the clock :)
NOT WAITING ANY MORE!
You guys going to Capital? Let me know and I will join you. They open around 4-5pm for test and tune every Friday night. don't forget your helmet.
I was hoping to get you to drive my car, maybe we can get something going. I have never drag raced before and do not think I would get a good launch with no experience. Lets see if we can find a Friday when we can all meet up. I am in North Carolina now but will be home sunday and can check my calendar.
I was hoping to get you to drive my car, maybe we can get something going. I have never drag raced before and do not think I would get a good launch with no experience. Lets see if we can find a Friday when we can all meet up. I am in North Carolina now but will be home sunday and can check my calendar.
Chuck
We can teach you to launch, it is easy in an automatic.
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BIX A BEL Cool, Ebony leather, Chrome, loaded, no XM/onstar Founding member of the "Lost Sols Club"
Deposit (1100) - 9/29/05, 1101/1102 - 2 Feb 06, 2500 - 7 Feb 06, 3000 - 8 Feb 06, 3100 - 13 Feb 06, 3300 - 13 Feb 06, 3400 - 14 Feb 06, 3800 - 24 Feb 06 (112544), 4000 - 24 Feb 06, 4150 - 24 Feb 06
dealer expected deliver 6 March, arrived 28 Feb, picked up that night w 3.2 miles on the clock :)
NOT WAITING ANY MORE!
Linear Mode
