Tune for trans shifting question....
#1
Team Owner
Pro Mechanic
Thread Starter
Tune for trans shifting question....
This is going to be a weird one, but please bear with me;
Can you install a tune, that will make the trans behave like it has a manual valve body?
Can you install ^that^ tune, and include a feature where the converter will stay locked until, say, 90% throttle?
IOW, lets say I have a long hill I can climb in my stick shift C4 in high (6th) gear. But let say that my wifes auto C5 won't do it in OD, b/c long before you get to even 1/2 throttle, the thing unlocks the converter, then down shifts. Now in 3rd gear, her car has too much power/tq for the hill...you're accelerating, so you let off the throttle, eventually, it upshifts, and again doesn't have enough b/c you can't exploit all the engine's tq in OD.
Can you "tune" to have control over when the trans shifts, and when the converter unlocks? Thanks.
Can you install a tune, that will make the trans behave like it has a manual valve body?
Can you install ^that^ tune, and include a feature where the converter will stay locked until, say, 90% throttle?
IOW, lets say I have a long hill I can climb in my stick shift C4 in high (6th) gear. But let say that my wifes auto C5 won't do it in OD, b/c long before you get to even 1/2 throttle, the thing unlocks the converter, then down shifts. Now in 3rd gear, her car has too much power/tq for the hill...you're accelerating, so you let off the throttle, eventually, it upshifts, and again doesn't have enough b/c you can't exploit all the engine's tq in OD.
Can you "tune" to have control over when the trans shifts, and when the converter unlocks? Thanks.
#2
Melting Slicks
Not fully grasping exactly what you are asking, but yes, you can control pretty much everything the trans does, including when (per TPS%) it shifts into each gear, and where the TQ locks up. You can set the speed per TPS % it locks up at in 4th. (mine is set to NOT LOCK in 2nd or 3rd).
Keep in mind, however, that setting it very high will effect you gas mileage and trans fluid, since the converter will still be slipping at "highway speeds)
Keep in mind, however, that setting it very high will effect you gas mileage and trans fluid, since the converter will still be slipping at "highway speeds)
#3
Team Owner
Pro Mechanic
Thread Starter
Yes, I'd be doing the opposite; I'd want the converter to STAY LOCKED when it won't from the factory. And I'd want it to STAY in a higher gear where it won't from the factory.
I want it to exploit all the engine's tq, before it unlocks and down shifts....not unlock and down shift, long before you have been able to get tq from the engine. You can always use the shift lever to down shift....doesn't work the other way around.
I want it to exploit all the engine's tq, before it unlocks and down shifts....not unlock and down shift, long before you have been able to get tq from the engine. You can always use the shift lever to down shift....doesn't work the other way around.
#4
Pro
Yes, I'd be doing the opposite; I'd want the converter to STAY LOCKED when it won't from the factory. And I'd want it to STAY in a higher gear where it won't from the factory.
I want it to exploit all the engine's tq, before it unlocks and down shifts....not unlock and down shift, long before you have been able to get tq from the engine. You can always use the shift lever to down shift....doesn't work the other way around.
I want it to exploit all the engine's tq, before it unlocks and down shifts....not unlock and down shift, long before you have been able to get tq from the engine. You can always use the shift lever to down shift....doesn't work the other way around.
You will need a scanner program to take logs of your transmission as when it shifts normally, part throttle, and wot.
you will also need to know your max torque at (X) RPM's and the torque curve which will be given to you via a few dyno pulls.
from that data you can tune your trans to shift at the desired torque or RPM. Good luck as it will take quite a few logs as far as cold shifting and normal op temp, as well as the variables I posted up top of this.
#6
Team Owner
Pro Mechanic
Thread Starter
I would likely do it myself or with a friend who has had experience tuning w/EFI Live.
#7
Le Mans Master
Member Since: Aug 2005
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St. Jude Donor '13-'14-'15
1st of all --the TCC upshifts and downshifts are commanded by only 2 parameters
1 is the throttle position and the other is MPH
So YES you can alter when the converter locks or unlocks based on TPS or MPH
It is however trial and error unless you have a data logger where you can see the TPS position where the changes happen exactly---
The simple way to remember how changes affect the TCC lock/unlock at part throttle is to remember that------
In the P/T TCC tables In the lock-up tables the TCC will lock up at the MPH you input at that MPH or anything HIGHER
In the P/T TCC tables in the UNLOCK tables the TCC will un lock at the MPH you input or anything LOWER
At WOT the TCC will unlock always regardless as long as the TPS exceeds approx 85%
1 is the throttle position and the other is MPH
So YES you can alter when the converter locks or unlocks based on TPS or MPH
It is however trial and error unless you have a data logger where you can see the TPS position where the changes happen exactly---
The simple way to remember how changes affect the TCC lock/unlock at part throttle is to remember that------
In the P/T TCC tables In the lock-up tables the TCC will lock up at the MPH you input at that MPH or anything HIGHER
In the P/T TCC tables in the UNLOCK tables the TCC will un lock at the MPH you input or anything LOWER
At WOT the TCC will unlock always regardless as long as the TPS exceeds approx 85%