Converter is a yank pt3200, basically a badass $1000 converter that should do what its told, and trans is a freshly rebuilt 4l80e by Gilbert. Im using the relay method to control the trans on the 60e tune.

Trouble is when the converter "locks" the scanner still shows a TCC slip of ~160 rpm. This increases to ~300 under load. I can tell it is at least partially locked due to the rpms not dropping with removal of the throttle, and the rpms rising steadily with more throttle. Trouble is I dont know if it is actually slipping or if its just an error in the scanner... I have tried using the speed sensor in the rear of the trans versus the tcase and no difference.

Any ideas?

 

I know that it may not be the same but does the input shaft for the pump have the oring on it to seal the tc so it doesnt leak fluid pressure for lock up.

 

Yes, that oring is fine, I made sure to check it before I put the torque converter in. It is also my understanding that if it was not installed correctly the converter would not lock at all.

 

Was anything done to the hydraulics to remove PWM and has PWM been completely removed in your tune?
Also to double check the scanner, log engine RPM vs input shaft speed vs output shaft speed in 3rd as they should all be the same with the converter locked and nothing slipping.

 

The PWM hasnt been touched in the trans, and the PWM min duty cycle is set to 99% and max to 100% which should make it basically an on/off switch.

Logging those might be an issue because on the 60e tune there is only 1 speed sensor that can be used. I have to use either the rear trans or on the tcase for the speedo to work correctly, which leaves the front ISS by itself.

 

I am not familiar with the 80e so much as the 60e, but I had a 'small' tear in my oring (assuming from converter install, dunno) and I had a very similar situation as to what you had, small amount of converter slip. At least on the 60e's even without the oring, I had a partial lockup.

 

have you tried commanding 100% DC for the TCC?

 

I talked to Gilbert this morning and he said in all the years hes been doing transmissions hes never seen the oring actually tear, hes seen it flatten from years of wear, but not tear. Also I should be having more issues than I am if that oring was compromised. He suggested I bump up the line pressure in low throttle regions to see what that does. I havent tried 100/100 TCC settings, not sure what kind of behavior that would cause.

 

Whats your minimum duty cycle at now? I run 98/100 and have the same issue.

 

As I said before, 99/100