4l80e vs th350 power issues

[kustomd]

I've searched through the forums for 2 days but can't seem to find the information I'm looking for.
Why does the ecu have to pull timing out of the engine to lower power on shifts to protect the transmission vs just letting the power build like older carbed engines did. I have a junkyard th350 that gets abused alot and it shifts fine throughout the rpm range of the engine without breaking. Both my 6.0l and the old sbc that's in front of the th350 are in the same power and torque range.
I understood the factory does it on LS stuff because they need them to pass emissions and live till the warranty runs out. But everything I've read says if you turn torque management off where it's not pulling timing and everything out on the shifts it will break the 4l80e. Are they really weaker than my junkyard th350 and th400s dinosaurs?

And I'm sorry if this has been covered somewhere in another thread I just haven't had much luck with the search function actually finding an answer to my question. I've watched a bunch of videos but they don't say much about the comparison between how the older stuff holds up better to full timing and fuel all the time vs the newer stuff that has to be stepped down in between shifts to keep from grenading it.

[blindsquirrel]

Will the friction material last longer if it makes the shift while the engine is making 90lb-ft, or if it makes the shift while engine is making 450lb-ft? Which will make less heat? Which will put less shock load through all the oily bits?

Will it break instantly if you turn it off? No. Will it break something sooner than if you didn't turn it off? I sure think so.

[RDF1]

It also changes how the shifts feel. Ever driven a stock truck with a 6L80E? the shift terribly slow and it kills all the power between shifts. the newer stuff doesnt need for the timing/throttle to be tamed down for a shift to happen. They do that for the folks that will complain about "Harsh" Shifts.

I have a few 900hp turbo trucks with stock 4l80es in them controlled by Holley ECUs. No torque management and they have been problem free for years. But they were tuned with a pressure sensor on the transmission to get the pressures where they need to be.

[kingtal0n]

Torque management will help the components last longer. I always use it. It can also help with traction between gears.

The HPTuners ECU usually has 2 maps anyways. I have one programmed with alot of TQ management and one with very little. You press a button and flip between them as desired.

I drive around with lots of torque management to keep the trans happy for a long time, minimal slippage and minimal component heating, less frequent rebuilds hopefully.

I turn it off when I really want to set the tire spinning between gears to send the car sideways spill my drink and scare the shit out of whoever is to my right possibly crashing into a wall or something

[kustomd]

I just wondered because I don't like the soft shifts and slow acceleration. I downloaded the blue cat table maker but I don't want to smoke my transmission right out of the gate but I like a firm shift and I want the power to be there when I need it. Like my old junk has. And it bugs me when I'm on the throttle hard I feel the power drop off right at the shifts.

[RDF1]

Bluecat is just for Up/Down Shifts and TCC lock/unlock. Doesnt have anything to do with Pressures or TM.
Upload your tune and a datalog.

[kingtal0n]

I just wondered because I don't like the soft shifts and slow acceleration. I downloaded the blue cat table maker but I don't want to smoke my transmission right out of the gate but I like a firm shift and I want the power to be there when I need it. Like my old junk has. And it bugs me when I'm on the throttle hard I feel the power drop off right at the shifts.

This sounds maybe an issue with volume and pressure of the transmission, or perhaps you just need more power (I am running 600rwhp usually). I feel the minimum power for 4l80e is about 600rwhp, you should use the 4l60e if you are less than 550rwhp IMO. The 4l80e is a momentum monster and it can easily- even with max torque management- spin the tires profusely during a shift. I have mine set to basically pull all power and it still spins like crazy and even chirps the tires at part light throttle. I lift from the throttle a bit just as it goes to shift and I even get tire spin while lifting from the throttle during a shift. It's because 4l80e has heavy internal parts which store kinetic energy that is being bled into the drivetrain when the gear ratios change, new ratio, new output shaft rpm is different than old output shaft rpm, energy dissipates to the tires (friction of the road allows tirespin) or accelerates the vehicle (friction of tire doesn't break traction). I've been thrown forward by the trans going from 2 to 3rd uphill, like it picks the car up and throws it.

My 4l80e didn't do all that until I rebuilt it, though. The factory separator plates and OEM clutchs (worn out for 20 years I guess) were not chirping the tires and they slipped during shifts to account for tire traction.
During the rebuild, we do a few things to enhance 4l80e shifting. The plate 2-3-4 holes are drilled for increased volume flow. The direct drum is dual fed. Clutches are brand new. Updated boost valve.
Also the factory pressure isn't turned up where it needs to be for performance engines making significant power (500-1000rwhp) at least in my gen3 original files I looked at.
After the rebuild you have to put a pressure gauge on the trans and dial the pressure properly. Then, with the new clutches and proper sized holes in the plate, you can use torque management or not and it won't make much of a difference, the thing will still throw the car around if you have good tires or set you sideways if you don't