Mort

Well I have had the HD2 installed for a while and it has made quite a difference. The shifts are a lot firmer and #2 is maybe too firm at light throttle. The WOT shifts are very firm in 2nd and 3rd and maybe too hard. The medium throttle shifts seem fine. I have not touched the tune yet put I plan to put the force motor table back to stock then all the shift settings will be stock with the exception of the shift timings which are .250 sec across the board. I also think I will remove all TM and Abuse mode because I no longer see the need for them and they don't seem to be effective with the HD2 installed..

Last fall as an experiment I tried a 2WD launch with 2500 rpm brake stall to about 2.2 psi boost. The truck lite up both rears for about 100' and then stopped during the shift for 30' and lite up again for about 50' in 2nd gear. Well yesterday I did a similar lauch in 2WD by error. I forgot to put it in 4WD by mistake. Well there was no comparison to the launch from the fall. The truck lauched a lot harder with both rears spinning to beat the ban. The black marks are definately a lot blacker and more solid. The truck did not stop spinning even a little during the shift to 2nd and the marks did not change color at all. After the shift (I think, LOL) the rear of the truck started to come around so I had to correct a little. I over corrected and it started to slide around the other way so I chickened out a let out of it enough to stop it from sliding around. It did not stop spinning though and I think it spun all the way to the shift for 3rd.

Wow I was really impressed.

Time for tuning.

moregrip

iTrader: (8)

good deal bro, the shifts will get better once TM is removed and shift pressures are back to stock

Quik

iTrader: (7)

do you need a tissue? firm shifts are the best and least amount of damage on the trans.

James B.

iTrader: (1)

I also would return line pressures back to stock level and start there. The shift kits makes up the shift firmness with hydraulic volume instead of pressure.

If they feel like they are too firm, resetting the duty cycle tables will help.

Shifts too firm put a lot of impact on the hard parts. Even though there are no aluminum torque-transfering parts in the 4L80-E like there are in the 60-E, harsh shifts still do damage. It will cause the splines to loosen up and the gear train to get sloppy over time. It's also hell on the rear end. You are making the right choice in toning it down a bit.

Is your reverse engagement now delayed a little bit? They do that to prevent burning clutch material going between drive and reverse.

Mort

Thanks Grippy I am going to try and get it done today.

Mort

No tissue required here man. I am happy as a clam.

Mort

James - thanks for the info it is always nice to know why a change should be made and where to make it. I have not really noticed a change in the shift delay to reverse but the shift to reverse is not harsh. I will try to pay attention to it to see if I can notice a bit more delay to reverse.

Thanks again.

moregrip

iTrader: (8)

now that is interesting as I did not know that, good info

moregrip

iTrader: (8)

have you seen my TQ mgmt removal thread? should make it easy for ya

Mort

I sure do thank you very much. I have a copy of it in my tuning file.

I am using Tuner Cat so I don't seem to have access to all the tables you do and TC is organized a little bit differently but it sure came in handy. I just flashed it into the PCM so I am going out to test it out.