Newbie 4L80 owner, is this how stall should work?
11-05-2011, 11:03 AM
#81
We can definitely tighten your converter up, logistics is the problem. There are also benefits to a looser converter on a turbo setup, it spools easier and faster so staging is not a problem. If you want to shoot me an email be glad to see what we can come up with.
Chris
Chris
08-07-2012, 10:47 AM
#82
I don't quite trust that, I'd log engine RPM and output shaft RPM and compare them.
Assuming 5400 rpm engine rpm and 4400 Dshaft rpm, driveshaft, thats a tick over 20%. It will probably be more efficient if you can turn more RPM (usually converters lockup more in the 2nd 1/8 mile compared to the 1st).
Assuming 5400 rpm engine rpm and 4400 Dshaft rpm, driveshaft, thats a tick over 20%. It will probably be more efficient if you can turn more RPM (usually converters lockup more in the 2nd 1/8 mile compared to the 1st).
In 3rd at 5800rpm trans shafts turn at 4750, then trans rpm catch up engine a bit. Too much or not?
08-07-2012, 06:16 PM
#84
Not sure if this was discussed in the earlier pages, but I don't think the later 4L80E has a "hard" on-off lockup solenoid - does it? I think the solenoid(s) applies pressure as needed depending on a variety of variables. This might result in some slip if engine torque spikes. I think this is done to protect the transmission, though I could be wrong.
08-07-2012, 09:02 PM
#85
TECH Senior Member
The TCC apply is ramped up to soften the feel (perceived by non-car persons to be a good thing), but once it's locked it does not slip;
if it slips then it's going bad or the engine has too much torque and needs a better TCC (multi-disc);
the TCC will quickly go bad if it slips for any significant amount of time (and will most likely take out the rest of the trans with it);
the PCM uses other means to protect the trans/powertrain (torque management).
if it slips then it's going bad or the engine has too much torque and needs a better TCC (multi-disc);
the TCC will quickly go bad if it slips for any significant amount of time (and will most likely take out the rest of the trans with it);
the PCM uses other means to protect the trans/powertrain (torque management).
08-09-2012, 01:30 AM
#87
he was probably answering the other guy 
Regarding efficiency, I don't have much data yet from 1/4, only good log I got shows that at 5800 TC slips about 1000rpm and at 5900 about 820rpm, and engine rpms climb very slowly from 5800 to 5900, while TC seems to be catching up a bit
Regarding efficiency, I don't have much data yet from 1/4, only good log I got shows that at 5800 TC slips about 1000rpm and at 5900 about 820rpm, and engine rpms climb very slowly from 5800 to 5900, while TC seems to be catching up a bit
08-29-2012, 04:34 AM
#89
Another idea I got to improve my terrible mileage is paddle shifting my 4L80 and manually locking converter, to act more like manual tranny and use more low revs around city.
probably would need some interceptor box then, that would intercept signals from PCM to tranny solenoids?
probably would need some interceptor box then, that would intercept signals from PCM to tranny solenoids?
06-14-2013, 03:29 AM
#90
I checked logs from last race and by the moment gear is changed, engine rpm is 6000, and input shaft around 5200. engine rpm climb very slow and converter is catching up. Does it mean I should adjust so it changes gears later? Maybe some 6200rpm
07-04-2013, 05:54 PM
#99
Jake, I've created separate thread to get help with this trouble, could you please check and give your ideas?
https://ls1tech.com/forums/automatic...ear-4l80e.html
https://ls1tech.com/forums/automatic...ear-4l80e.html