Trans specialists in here

BLOWN38

SCCoA Member
Ok guys I think I know what is happening with my 1-2 shift. I think the converter is starting to lock at the top of 1st gear. If you look at these 2 logs both show a notch at 5700 rpm. I have the tune set up to complete the 1-2 shift at 6500 rpm. But as you can see it happens about 500 rpm too early in the 2nd log. This all started when I installed the triple plate.

Now the difference is the first log is a PI single plate and the second is DD triple plate. The triple you can see has some holding power.

In 1st gear when it starts to lock it actually pulls the RPM's down and then you can see after the shift is complete the point is sharp at the bottom.

Now the question is what can cause the converter to try and lock in 1st gear when its supposed to be impossible? Cooler lines too small? Bad solenoid? Valve Body problem? Case problem?

Did i mention, DAMN I LOVE THE QH!!!:D
 

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It cannot be lockup, it is the converter sprag switching to freewheel for efficiency and working as it should. When the turbine speed gets close to the impeller speed the stator will begin to free wheel allowing the fluid flow a direct path which in turn dramatically decreases the stall giving you a feel the appears to be lockup. If you measure it accurately you would think the converter clutch is engaged but slipping about 3%
Alan
 
so you say everything looks normal? so i would have to raise the shift point higher to get past that point where the engine is not accelerating as fast to get it to shift at 6500? the shift point is 5500 in first. so maybe go to at least 5700 where the rpm drop occurs? and hope it don't blow by 6500 by the time it completes the shift.
 
There are many variables in that. you have to play with it a bit. Just because the shift is commanded at 5500 does not mean it will shift there. It depends on the time required to complete the shift and the electronic delay.
Alan
 
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