[Ilma]

This isn't a big issue.....but I was wondering if anyone can help me to troubleshoot that little bit of boost wobble you see below on this run when I shift from 3rd to 4th. The boost holds so smooth, but then the shift seems to disrupt it for about a second.

Other logs I see on here don't seem to exhibit as much.

I'm running the latest V4 maps.

This is a stage 1 map at default settings except for future value = 41 which is about the smoothest I can get the learning gain.

I have 6AT with DCI, stock exhaust and stock downpipes and 94 octane.

[OpenFlash]

Try raising the upshift softening a bit. It will result in more throttle closure between shifts and drop boost so it can recover cleanly. But if you want to see something funny, run it in valet and see how poorly the stock tune handles this transition. You'll be amazed.

shiv

[Ilma]

Originally Posted by shiv@vishnu

Try raising the upshift softening a bit. It will result in more throttle closure between shifts and drop boost so it can recover cleanly. But if you want to see something funny, run it in valet and see how poorly the stock tune handles this transition. You'll be amazed.

shiv

Lol...yes I remember seeing my boost gauge oscillate at the shift when I took my tune out about a year ago. Was very apparent!

I have actually played with the upshift softening.......but found that it didn't help much.

Just seems to be something about my car.

But I am splitting hairs here because the event is so minor and lasts about 3/4 of a second.

I am just getting closer and closer to dialing in my car....the timing curves no longer seem to dip since I added about 5% more ignition correction.

Just trying to get the boost shift transition as smooth as yours - but then I am AT and you are MT....so maybe this is apples to oranges?

[OpenFlash]

Originally Posted by Ilma

Lol...yes I remember seeing my boost gauge oscillate at the shift when I took my tune out about a year ago. Was very apparent!

I have actually played with the upshift softening.......but found that it didn't help much.

Just seems to be something about my car.

But I am splitting hairs here because the event is so minor and lasts about 3/4 of a second.

I am just getting closer and closer to dialing in my car....the timing curves no longer seem to dip since I added about 5% more ignition correction.

Just trying to get the boost shift transition as smooth as yours - but then I am AT and you are MT....so maybe this is apples to oranges?

Yep, totally apples and organes. With the 6MT, a certain amount of boost is lost between shifts due to throttle closure and bypass valve venting. This makes it easy on the boost control system to spool back up and hit the boost target cleanly.

In the case of a 6AT, there is no (or very little) throttle closure or bypass valve vending. And on top of that, there is a big increase in manifold pressure/boost as the revs drop 2000rpm during the upshift. So the tune has to drop boost actively to compensate for this, while still catching it once the revs start to rise. Very different challenges.

Shiv