2015 5.7 Torqstorm - ZF8 Will Not Shift When Commanded

[Full Throttle Steve]

I am tuning a 2015 Challenger 5.7 /ZF8 with a Torqstorm Supercharger Added to It.

It's made good power but now I am working on the transmission and can not for the life of me get it to shift when I want. I've played with the shift tables and targeted the RPM I want it to shift at during a WOT situation but something isn't right.

I am thinking it has to do with the torque configuration...

If I am targeting say 6100 RPM at WOT in third gear on a downshift scenario, it acts like it fuel/spark cuts at 4800 RPM.

I attached a log and the tune file to look at.
I would greatly appreciate a bit of help.

[email protected]

StreetTest1.hptTransTuning.hpl

[LilSick]

I can help with that

Good data is key

Scanner has many parameters for your TCM and PCM

Shoot me a email

[DodgeBoy_8HP]

I am tuning a 2015 Challenger 5.7 /ZF8 with a Torqstorm Supercharger Added to It.

It's made good power but now I am working on the transmission and can not for the life of me get it to shift when I want. I've played with the shift tables and targeted the RPM I want it to shift at during a WOT situation but something isn't right.

I am thinking it has to do with the torque configuration...

If I am targeting say 6100 RPM at WOT in third gear on a downshift scenario, it acts like it fuel/spark cuts at 4800 RPM.

I attached a log and the tune file to look at.
I would greatly appreciate a bit of help.

[email protected]

StreetTest1.hptTransTuning.hpl

People will support you around here.

A couple of important PIDs are missing in the log. However, I can see:
- TM: Improvements on Shift schedule, torque converter, pressure and timing.
- Engine: Torque management and spark tables

[Full Throttle Steve]

So I can now get it to rev to target shift point of 6100 rpm, I had a throttle torque source issue prior causing an RPM Limit.

The shifts feel incredibly lazy. There is no pressure or crispness at the shift at all.

[Full Throttle Steve]

Updated Log and Tune Attached...

StreetTest8.hpt
StreetTest8Log.hpl

[DodgeBoy_8HP]

Definitely the tune could use some work on shift pressure and torque converter set up.

Depending on vehicle use, shift schedule could be changed as well. Which driving modes do you have?

On engine side, at a glance, speed density, torque management and spark. Also, based on log, upshift happened at 5650rpms

[LilSick]

steve, stop fkn around with downshift scenario

i would fix the engine tune before working on the trans whatsoever if i were tuning it

THEN, move to upshift tuning

downshift is last

looking at the engine tune, the lack of channels, and the driving technique while logging, you could use some help

i can help you if you would like?


*dunno where the 5650 number came from

the input shaft of the transmission at 5727 rpm in the shot i posted

and that was not peak

doesnt matter cuz like i said, you need to address other issues first

[DodgeBoy_8HP]

steve, stop fkn around with downshift scenario

i would fix the engine tune before working on the trans whatsoever if i were tuning it

THEN, move to upshift tuning

downshift is last

looking at the engine tune, the lack of channels, and the driving technique while logging, you could use some help

i can help you if you would like?


*dunno where the 5650 number came from

the input shaft of the transmission at 5727 rpm in the shot i posted

and that was not peak

doesnt matter cuz like i said, you need to address other issues first

Correct on input shaft: 5722 rpms

Wrong: Driver see engine rpm, not input shaft. Engine: 5650 rpmsengine rpm.png

[LilSick]

So you believe at wot the trans input shaft was driving the engine while up shifting from 2nd to 3rd gear?

Interesting concept

Completely impossible, but interesting : )

[DodgeBoy_8HP]

Never said transmission is driving the engine

I wrote: input shaft is 5722rpms / engine is 5650 rpms. What driver see in the dash is engine rpm not input shaft.

Values from log.

There are a couple of potential reasons for the difference between both values

[LilSick]

my point was that the guy is dead in it in second gear and the input shaft rpm sensor is reading 5735

there is no way the trans shifted at a engine speed of 5650 as was suggested

[DodgeBoy_8HP]

Yes, the part the tune is not correct, we completely agree!

The part we dont agree is engine rpm, which is fully fine! Good discussions are good to everybody to learn.

I guess the simple fact of "system message delay" could be a huge factor here.