[ghtyr]

Hey Guys,

Been a while, had my setup nicely dialled in for a couple years and figured I'm well past due to update things. Got the 5.17JB4 firmware and did the latest BMS PUMP BEF. Went with the THR file but wasn't clear if that's the one I should have chosen after reading through the 46 pages of the BEF thread again. Open to hearing if I should just go with the regular PUMP file or not, would appreciate guidance there please and thank you gents.

In addition, looking to get the dip after spool evened out. When going full throttle and WGDC goes to 99 to spool the turbo, once I hit target PSI and WGDC drops, my boost is dropping below target and then correcting back. I feel it's an issue of WGDC just dropping too low after spool and could use adjustment. My gut says raise the Duty Bias at 3500RPM where WGDC drops out of spool mode, but I also was considering that the menu 11 setting might be affecting that also? Thought I'd check in here first. Also, lots of settings got changed when I updated the JB4 firmware so I am requesting some help here to get those back to a clean state.

Few other things to address but that's plenty for a start!

Mods in Signature, the pull pictured is at the end of the csv file. Let me know if there's other info or additional full pulls required to advise. As always, really appreciate the help

[Steve @ BMS/Fuel-It!]

Too many pictures and a long description.

Looked at the log, don't see any issues, looks pretty normal and like you may have a couple traction issues. Traction control off?

Best logs are from 2k to redline in 3rd or 4th at WOT.

[ghtyr]

So I played around with Duty Bias a bit yesterday and got the dip after spool smoothed out (see first image attachment).

The problem with that arises in real-life driving conditions, such as shifting from 3rd to 4th under WOT, where revs don't drop to the same RPM when spooling post-shift, and I get the same dip after spool (see second image attachment for a 3rd to 4th gear shift).

CSV attached and edited to show the data from just the two images.

Does anyone have a different approach to fixing this after-spool dip that isn't RPM based duty bias tuning?

Also, I read somewhere that 6-speed manual transmission models will pull timing when torque kicks in. You can see my timing plummets at the beginning of the 3rd gear pull, even though boost is not yet higher than my gasoline octane + meth can handle. Is there a solution to tuning that out?

Let me know if I'm not posting things correctly here, maybe it's just because of the weekend and it's Monday now or maybe I'm just being paranoid as to why I'm not getting any responses on this post and need to be patient hahaha

Thanks!

[ghtyr]

Oh hahaha just as I was typing that reply about responses! Ya, I wanted to make sure I outlined the issue and have all my JB4 settings shown. I'll work on being more concise!

Traction control is off fully long push, and zero wheelspin thanks to xDrive What do you think of the latest 3rd gear proper log I just posted?

[drwillb]

Dial back your default wastegate setting. Currently set to 80 but I would bring it down to 50 and work either way from there.

This setting now controls spool duration. 80 = hitting 80% of target then dialing back WG. On my car I was getting a lot of overboost and boost crash until I dialed this back.

[ghtyr]

Oh man, that seems like exactly what's going on here. Just haven't had to keep up with settings updates the last couple of years as my setup has been dialed in for quite some time now, so was feeling a bit lost since updating firmware and BEF. So I maybe I'll set default wastegate pos to 50, reset all my duty bias to 50 across the board, maybe increase PID Gain to 25, do 3 or 4 pulls to let that adjust out and settle, and then fine-tune things from there? Any thoughts on that process, kind of a start-from-scratch approach? I wonder if that will help with the timing crash early in the low RPM range of the 3rd gear pull?

[drwillb]

I just realized you have a PS2. That brings a lot of particular tuning with JB4. PS1, which I have, is a lot easier. Just spend some time reading the big turbo thread for some insights. Used to be PS2 was the big boy but now there are much bigger ones.

[ghtyr]

So made the adjustments and did 6 3rd gear pulls to redline last night. It was somehow 30 degrees celsius up here in the Edmonton northern wasteland and she didn't get much of a break between pulls, so I'm wondering if either that was affecting timing, or just the car/jb4 adjusting to the changes (probably a bit of both?). The first few I accidentally had DWP at 60 and was still getting a bit of a dip after spool, but when I noticed that and put it back to 50, the dip went away, so great advice on that one! The car seems to be used to having high values for duty bias up top where it is straying far below target. I confirmed there is nothing mechanically wrong by running map6 and hitting 22PSI to redline with moderately medium WGDC numbers. I'm going to reset all adaptations and leave it here for a while and see how it settles down. I think in a few weeks I'll see where it's at and report back before making the final adjustments with the RPM-based duty bias values.

Is there anything you guys are seeing that I'm missing, or anything in my plans that you would have different or additional suggestions for? Really appreciate the input and hopefully this can be a good reference for future people looking to dial in the latest firmware and BEF for similar setups to mine.

The picture is from the 6th and final pull.

[drwillb]

Looks like you'll want to stick with map6 and custom duty bias in order to get your FF and WGDC lines closer. Your FF is already at 90 so do manual DB values. You can also shut off auto FF adjust so you're not fighting against JB4 while dialing in your curves.

[ghtyr]

I'll want to see how things settle out after a while before I start adjusting, I think. Am I correct in saying that my low timing during spool and throughout the pulls contributes to higher WGDC values as the turbo needs to work harder to reach boost values? If so, letting the current settings settle, allowing the timing to clean up and stay higher, will bring WGDC closer to FF. I also am coming up on doing my oil change so having clean fresh oil should help as well, correct? Fresh oil, settled tune, and less heat soak should be better conditions to start tuning duty bias for someone who does not track the car and mostly dd with maybe one or two WOT pulls per week, correct?

At that point, if the gap is still large between FF and WGDC on map 3 here, I will definitely go back to Map 6 as you say. I did a pressure test and everything held perfectly strong just as an aside to rule out a leak.

[Steve @ BMS/Fuel-It!]

The gap between FF and WGDC needs resolved first.

Set all your DB's to 65 and your FF to 100. Then you can fine tune the DB's as needed to get your FF and WGDC curve to match.

User adjustments to FF and DB's are for all maps...not just map 6, that has nothing to do with it. Otherwise the log itself looks pretty clean.

Your data drop-outs...are you running anything else to the CanBus?

[ghtyr]

Thanks Steve! Looking much better. I was editing the csv’s to make the gaps between pulls shorter. I like to freeze the top cells and the left columns for easier review also, then I re-save the csv. Anyways, been having some fun dialing things back in. Making good progress and will post updates as I go. Here’s a fun one where I overshoot quite a bit:

[Steve @ BMS/Fuel-It!]

Yep, duty biases need more tweaking. I'd start at 40 and scale them by 5 like you are but then may need to adjust FF as well. Get the FF curve shape adjusted with DB's and raise of lower the curve with FF.

[ghtyr]

I also noticed that when I updated my JB4 firmware, Bit 6 is enabled. From the JB4 sticky: bit6 - Disable FF RPM gain so duty bias RPM gain can be manually set more precisely.

This sounds like I actually don't want this selected, correct?

EDIT - Or maybe I do want this selected...as per the Large Turbo Tuning thread first post under E Series: "Note FutureUseD=64 disables "RPM FF Gain", which allows you to manually enter a duty bias curve that is more appropriate to larger turbos"

Having a PS2, this makes me think there is tuning I don't know about that can improve performance of my PS2 further?

What is the difference between locking FF adaptation+adjusting duty bias values, and disabling RPM FF Gain? When you disable RPM FF Gain, then what do you adjust to make it more appropriate for larger turbos? There must be more information on this somewhere that I'm missing, but I searched on here and googled to no avail. Can someone help point me in the right direction?

[Steve @ BMS/Fuel-It!]

No, you will leave it set so that you can dial it in manually and it's not another variable.

[ghtyr]

Ok so before this option was available and we were dialing in duty bias values, this FF Gain was altering things in the background making things difficult, and now this option to disable it is available and you can select it and it just makes things easier for dialing in those duty bias values, is that correct?

One thing on that, is it also the same process at the end when you’re done shaping your curve with duty bias values; where you re-enable FF adaptations, do you re-enable FF RPM Gain as well?

[Steve @ BMS/Fuel-It!]

Once dialed in, you can try enabling them but if you begin seeing WGDC and FF drifting, then I'd leave them disabled.

[ghtyr]

Makes sense, thanks Steve! Still been too busy to get out and do any pulls, doesn't help it's a heatwave in Canada right now, but I'm going to try and get out today or tomorrow and then post up the results.

[ghtyr]

Now that it's back to normal temperatures, I went out and did some logging runs. What I'm seeing is timing flatlines right out of the gate during spool. Can I get some advice how to get rid of those? I use Chevron 94 no ethanol added, and my CM10 and CM5 nozzles are spraying that 99.99% methyl hydrate I buy at home depot in the paint aisle. Picture is RUN 3 in the csv. Thanks so much!

[ghtyr]

I did some googling and found some posts about torque limiters on 6MT cars at low RPM hitting high boost (20PSI at 3500RPM). I have several questions on this:

1 - Could this be what is happening here?
2 - Is there a way to reduce the torque the DME sees at that RPM to eliminate the limiter and stop the timing flatline and boost decrease?
3 - How could I test to see if this is the problem?

Thanks so much for the help!

[Steve @ BMS/Fuel-It!]

Do you have something else connected that is intercepting the CANbus signal? I'd need a better log.

[ghtyr]

Maybe I'm messing up something when editing the csv. here is the raw csv unedited, does that help?

[ghtyr]

I’m gonna go ahead and call this one. Slipping clutch. That looks and feels a whole lot like a slipping clutch. FML. Spec 3+ and m factory single mass flywheel. Anything else that could be?

[Steve @ BMS/Fuel-It!]

Yes, that's better with the raw CSV.

The log I looked at was okay and didn't show any signs of slippage but the image you posted looks like it could be.

Looks like you are running the pump flash and timing will start low and ramp throughout the RPM range in that flash.