6AT Post shift timing corrections - lets end this.

[Jboyorak]

I haven't been active for 2 years(or done anything with my car), so my memory is fuzzy right now. I am just getting back into a place where I can play with my car once more.

IIRC, I ended up fixing my issues by never reaching target boost/load. I ended up tuning everything to the point where I was always just under targets. This fixed both post shift throttle closures and post shift timing drops. How I did this...I can't remember as of right now. I know it isn't super helpful, but with any luck I will be diving back into the tuning aspect of things

 

[all4bspinnin]

I haven't been active for 2 years(or done anything with my car), so my memory is fuzzy right now. I am just getting back into a place where I can play with my car once more.

IIRC, I ended up fixing my issues by never reaching target boost/load. I ended up tuning everything to the point where I was always just under targets. This fixed both post shift throttle closures and post shift timing drops. How I did this...I can't remember as of right now. I know it isn't super helpful, but with any luck I will be diving back into the tuning aspect of things

Anything is helpful. I've tried this approach several times with no effect. You can lower base wgdc table/adder airflow while raising load target to do this (proving p fact doesnt make up the difference). The problem mostly surfaces on e85 due to the higher torque, timing, etc. Im working on the approach RSL recommended. I hope to have more info soon.

 

[mfractal]

i'm experiencing the same issue. FBO w/o inlets on stock turbos. I'm tuned with V8Bait, the map is super strong and i am very happy with all aspects of it, all but the corrections post shift. We've tried different E-mixtures and many map revisions but unfortunately the post shift corrections are still there.

Hopefully MHD will introduce the timing re-introduction tables to all and that will help.

here's a log of mine btw : https://datazap.me/u/mfractal/justin-e50-rev03?log=0&data=3-7-8-9-10-11-12-24

 

[Jeffman]

Yep. Your Cyl4 timing pull is pretty massive. Have you tried any/all of the suggestions made in this thread?

 

[mfractal]

Yep. Your Cyl4 timing pull is pretty massive. Have you tried any/all of the suggestions made in this thread?

To be honest i do not know what was done in the map to try and correct it as i wasn't tuning it myself. @V8bait (Justin) was.

Cylinder 4 does seem to be the most affected one, i wonder what that means.

BTW here's a log with more agressive timing : https://datazap.me/u/mfractal/justin-e50-rev02?log=0&data=3-7-8-9-10-11-12-24

and here's one with much less timing requests, you can see it's totally clean : https://datazap.me/u/mfractal/justin-e50-rev01?log=0&data=3-7-8-9-10-11-12-24

 

[Jake@MHD]

Do the same corrections show up on a 2 gear dyno pull? If so, is someone able to get det cans on the motor and see if noise is increasing during the shift?

 

[bradsm87]

My Cyl 4 is usually the worst also. The least compromised option I can think of right now is probably to use aggressive timing reduction by charge air temp at around 5000rpm. That way at least you can get your full timing in a single gear run but pulling into a subsequent gear when IAT is higher, you can set it up to have less timing, making the drops less severe.

Still very compromised though but less so than simply pulling timing out of the timing main map.

 

[Jake@MHD]

So let's assume it isn't just extra noise during a shift (if so, the problem could be handled differently). Over how many ms do you think timing would need to be re-introduced in order to avoid the corrections?

 

[bradsm87]

So let's assume it isn't just extra noise during a shift (if so, the problem could be handled differently). Over how many ms do you think timing would need to be re-introduced in order to avoid the corrections?

I think 150ms would be a good starting point for testing and it's above logging sample rate so we will be able to see it in logs. From there, if timing drops get better, we could incrementally drop it back as much as possible without the bad timing drops.

 

[Jake@MHD]

150ms, linear ramp?

 

[bradsm87]

150ms, linear ramp?

Yeah that'd be a great starting point I think.

 

[all4bspinnin]

150ms, linear ramp?

Yes. Should work. Only one way to find out

Nice to see you in here asking questions. It means youre working on it.

 

[Cheezy]

@jyamona did you have any luck testing your 150ms reintroduction theory?

 

[Jake@MHD]

@jyamona did you have any luck testing your 150ms reintroduction theory?

So far it worked in an F-series test, but it was applied to every shift which made normal driving shifts slower and sloppy. It will definitely need some more work when time allows.

 

[mfractal]

So far it worked in an F-series test, but it was applied to every shift which made normal driving shifts slower and sloppy. It will definitely need some more work when time allows.

There's an F series with 6AT in it ? Wasn't aware..
So when you say it worked you mean post shift corrections were gone ?

BTW, you've asked above if it happens from 2nd to 3rd - just saw this this week on a friend's car. it does.

 

[Jake@MHD]

There's an F series with 6AT in it ? Wasn't aware..
So when you say it worked you mean post shift corrections were gone ?

BTW, you've asked above if it happens from 2nd to 3rd - just saw this this week on a friend's car. it does.

Not 6AT, but the logic is in the DME so trans is irrelevant. And yes corrections were gone.

 

[Rob09msport]

Yeah that'd be a great starting point I think.

Do you do pro tunes?

 

[Rob09msport]

I would want v8bait jyamona or you to tune my car

 

[doublespaces]

@jyamona doesn't do engine tunes, he more or less writes code in the ecu for the engine tuners to use.

The F chassis has only had an 8HP in terms of automatics, as far as I know.

 

[mfractal]

bumping this.. has there been any development in this area or those timing reintroduction tables in MHD ?