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Shift RPMs

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Old 12-31-2012, 12:01 AM
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Default Shift RPMs

Searched and didn't find answers. My WS6 came with a 3000-3200 stall and I was wondering what the Rmps should be vs what they are in my car. It shifts from 1-2 at fairly low rpms but in 2nd it will hit the 3000-3200 mark then shift into 3rd. Is it supposed to be that way?
Old 12-31-2012, 07:05 AM
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It shifts 2/3 at 3k at what throttle position? Like how far are you mashing the gas.
Old 12-31-2012, 08:20 AM
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Depends on what the part throttle tables command as shift rpm. Clearly the tune is holding 2nd gear longer than 1st gear. You need to get it tuned if you don't like it.
Old 12-31-2012, 01:01 PM
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It will shift 2-3 at 3000-3200 rpms during normal driving conditions. No mashing, no spinning tires (I would say at 1/4 throttle to half throttle). 1st-2nd shifts at 2k to 2200 rpms. It doesn't bother me but I'm going to do an H/C/I combo here soon and wanted to make sure I had at least a 3k stall (per the vets on this site) for the setup.
Old 12-31-2012, 03:32 PM
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Everything you have posted so far is highly dependent upon your tune, so...

In a safe location with plenty of room in front of you try this:
1. With trans in drive, hold the brake firmly with your left foot.
2. Over a period of 2-3 seconds, gradually increase throttle until the revs stop climbing while the car is NOT moving. The RPM where they don't climb much more is the approximate "stall speed".
3. Don't do this for more than 3-4 seconds because this test rapidly increases the trans fluid temperature. If you have to repeat, give it a good 15-30 minutes to cool back down, preferably with easy driving.

Again, this is the approximate stall speed, but should be within 500 rpm.

I'm not an expert, so watch for corrections or additional comments too.
Old 12-31-2012, 03:45 PM
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The shift is determined by speed and percentage of throttle in the tables.
The settings are pretty much by driver preference which makes it nice to have HPT to mess with them

I set mine just this week, and I like the change. Mine was getting into 3rd gear by 20mph at light throttle.
My first attempt had 1-2 shifting too late, didn't like that at all.
So now I have the 1-2 set to 14mph, and the 2-3 set at 25mph and 3-4 set to 35 mph.

I have a 3600 stall and this kept it from just stalling the converter all the time.

BTW....you can get close on the stall by the method Vedit stated, but it is highly dependant on how good the rear brakes are.

Ron
Old 12-31-2012, 04:50 PM
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Thanks for the info all. I got mine up to 1200 rpms for max stall. My T/A shifts at about 10 mph into 2nd then at 35 mph into 3rd (at 3200 rpms). It doesn't bother me I just wanted to know.
Old 12-31-2012, 07:00 PM
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Originally Posted by AmnSF
Thanks for the info all. I got mine up to 1200 rpms for max stall. My T/A shifts at about 10 mph into 2nd then at 35 mph into 3rd (at 3200 rpms). It doesn't bother me I just wanted to know.

It will vary depending on your throttle position...
It is not a "Fixed value" for all throttle positions...
it does not do part throttle shift by RPM's, it does it by throttle position and MPH



at low throttle position it shifts into the next gear sooner than at High throttle positions..

its determined by your tune and a table that has multiple values for all gears

WOT is determined by several tables... a Minimum MPH to reach before it shifts, and a desired RPM to shift at once that MPH has been reached...the MPH table is primarily used to determine when to downshift to a lower gear at WOT

there is also a desired shift time table, which is a learning table that makes your shfts more varied depending on other sensors... this table can be zero'd out to make it always shift the same regardless of other variables its using for shift calculations.

the only way to know exactly what it commands the shift at, is to either log data and plot it, or to read the tune and look at the table
Old 12-31-2012, 07:45 PM
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Makes sense. I'm no where near up to par with all the tuning values and how to tune. I've seen the acronym WOT tossed around quite a bit but still don't know what it stands for. Couldn't view the thread with all the acronyms. What's it stand for?
Old 12-31-2012, 07:46 PM
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WOT = Wide Open Throttle -
and just to be more clear and cover all the basis...WOT is when you mash your foot on the gas pedal and the throttle opens up all the way...
Old 12-31-2012, 08:31 PM
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Why didn't I figure that out thanks
Old 01-01-2013, 12:16 AM
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If you'd like to gain an understanding of what/how is being commanded of the transmission check Coolaids write up of tuning the AT. Even if you don't tune it can be extremely informative.

https://ls1tech.com/forums/automatic...tm-w-pics.html
Old 01-02-2013, 02:18 AM
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Thanks for that tuning link. I read over it and grasped the general concept. Lots of info to understand though.



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