redfirepearlgt
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Got the Circle D stage III 2C 258mm stall converter in the car last Friday. Driving it I notice some oddities (with respect to the factory converter) aside from the slightly higher RPM at take off which is to be expected. This is my first experience with a TCC style converter that is also computer shifted unlike old reliable C6's that you just throw a 2500 stall into and go. So with that said I will try to describe what I am feeling in hopes that 6R80 guys running Circle D stalls can possibly clarify as expected, a concern, or even able to be tuned out in the trans control portion of the custom tune.
The trans (and car) has 15000 miles on it. The transfluid was fine when we inspected it during the swap. Just topped off with refresh replace what was left in the old converter and the level verified. The setup is your basic 320 coyote supporting a 9-10 psi 2300 TVS making about 550 RWHP.
1.) Normal leave from a stop I notice that the 2-3 shift and converter lock up are more distinguishable after the trans temp is at temp than when the trans is under 80 degrees. It almost feels as if the trans is short shifting to 4th but the datalog clearly indicates its in 3rd. I know from the tuner we are locking the converter in second.
2.) There is a slight rise in RPM at shift point not felt with the factory converter. This is observed in the datalog I made of the car leaving from a stop. It's not flare like one would see when clutches are beginning to fail, just a slight raise in RPM just after the gear is commanded but just prior to the actual shift happening in the datalog.
3.) At cruising speed of 70mph (or other speeds that are steady) when letting off the throttle and then applying again this slight RPM surge is again felt (about 100 RPM) and then everything settles back in. This can also be seen in a second datalog I made at about 75 MPH.
I can provide these datalogs that can be viewed in excel or using livelink to anyone who would like to see them via PM.
Out of curiosity if you know a remote COYOTE tuner who actually does full tuning including the transmission in both drive, sport, and manual shift modes (mine is a 2014 6R80 with that stupid select-a-shift I hate) please also send me a PM on who did your tune. I may be ready to look elsewhere for someone who is as well versed in 6R80 shift strategy and tuning as they are on the engine side.
The trans (and car) has 15000 miles on it. The transfluid was fine when we inspected it during the swap. Just topped off with refresh replace what was left in the old converter and the level verified. The setup is your basic 320 coyote supporting a 9-10 psi 2300 TVS making about 550 RWHP.
1.) Normal leave from a stop I notice that the 2-3 shift and converter lock up are more distinguishable after the trans temp is at temp than when the trans is under 80 degrees. It almost feels as if the trans is short shifting to 4th but the datalog clearly indicates its in 3rd. I know from the tuner we are locking the converter in second.
2.) There is a slight rise in RPM at shift point not felt with the factory converter. This is observed in the datalog I made of the car leaving from a stop. It's not flare like one would see when clutches are beginning to fail, just a slight raise in RPM just after the gear is commanded but just prior to the actual shift happening in the datalog.
3.) At cruising speed of 70mph (or other speeds that are steady) when letting off the throttle and then applying again this slight RPM surge is again felt (about 100 RPM) and then everything settles back in. This can also be seen in a second datalog I made at about 75 MPH.
I can provide these datalogs that can be viewed in excel or using livelink to anyone who would like to see them via PM.
Out of curiosity if you know a remote COYOTE tuner who actually does full tuning including the transmission in both drive, sport, and manual shift modes (mine is a 2014 6R80 with that stupid select-a-shift I hate) please also send me a PM on who did your tune. I may be ready to look elsewhere for someone who is as well versed in 6R80 shift strategy and tuning as they are on the engine side.