2-3 is too harsh when the TC locks before the shift point (mid top heavy throttle) But on lite throttle the TC locks after the shift its perfect. I am hoping TW's shift points are a little different. No matter what I have full adjustablity (three different things I can change) to get the shift right where I want it.

 

and i suppose the 1-2 is too soft when the tc is engaged at wot?

 

No, TC never locks up before the 1-2 shift but if it did it would be break u-joints and axle harsh. The 1-2 might be a little tight right now. I haven't decided if I like it or if I want to back it off a little.

 

under wot it will engage on a warm trans at the shift, try going wot on a cold trans, it wont engage and the shifts yield a very light rpm drop as compared to the warm trans with converter engaged.

 

Well I will check that out but I don't think that is the case with my tuning. Either way the WOT shift at 1-2 is very nice.

 

thats good to know, i would bet the lack of epc controling pressure is behind the good shift there! most kits will still give a slight slide on hard 1-2's thanks to the tc engage

 

Joe I guess your right. I never realized how the TC locks at that shift at WOT. I always have my eyes on the road when at WOT. But the shift is still quite nice.

 

The C6 was controlled by vacuum, not RPM. That's what the vacuum modulator on the side of the trans did, it controlled line pressure based on engine vacuum.

 

The modulator was replaced by a pcm.
The modulator had 2 jobs. Adjusted line and when a shift occurs.
This from motor load (vac).

Bill

 

Oh.....Alright, I didn't know that. Thanks for the correction!

 

Mark

Your not a fan of tuners/chips ect.
What is your .02 with the epc when they are used?
"Mainly flip chips".

2nd question
Then add an X-brake with TC lock to open another can of worms.
Coast clutch takes a beating!

I have watched both from a line gauge standpoint.

Bill

 

I will admit I am kind of clueless about automatic transmissions, but if you are taking the pcm out of the trans operation, how will a chip help with transmission shifting or adjusting them?

I would also be curious if you see any mpg differences, assuming you can control yourself for a while so you can drive it similarly as before the mod.

I would like to do some sort of shift kit to firm up the shifts but I do not want them to be harsh either.

 

The only PCM control this kit removes is the line pressure control. Which is only part of the shift "feel" equation. The shift points are still commanded by the PCM. This will probably not increase mileage by a measurable amount.

 

I don't know much about chips, including "flip chips." I don't know what they do or how well they work.

The coast clutch in the E4OD and 4R100 is not the most robust clutch out there. Adding more load to it doesn't seem to me to be the way to make it last a long time.

The vacuum modulator on the C6 did work to control shift timing, along with the governor. The modulator also controlled line pressure.

If you use the ESE kit to replace the EPC, the PCM will still control when a shift happens, but it will not control how hard or soft the shift is. That will now be controlled by the ESE. I can't see that it will have ANY improvement in fuel economy, but it might have some loss of fuel economy.

One of the benifits of electronic pressure control (EPC) is that it controlls the correct pressure for the torque going into the trans. The older vacuum systems used to run a lot higher line pressure to make sure that the clutches and bands did not slip, especially when the trans was NOT shifting. With EPC the PCM calculates the torque the engine makes and commands the proper pressure to hold the clutches and bands with much less extra pressure. It takes torque from the engine to drive the pump, and the more pressure the pump is making the more torque is taken from the engine to drive the pump. It's enough to be worth a few percent in fuel economy.

 

Its surface area is way to small. Only has 2 friction plates.(oem)

X2. Trans is less efficient. (mpg wise)

Bill