6R80 3-4 Shift Flare

[Spooled]

Hello all. Looking for some feedback and some direction on how to improve my 3-4 shift. The vehicle was previously on 6lbs of boost and all shifts were great. Since bumping it up to 10, I'm getting a flare on the 3-4 shift and haven't been able to figure it out. I'm going to attach a couple of logs and a screen shot of a couple of tables. I've tried searching on here for some info, but haven't really found what I need. If anyone could lend some advice and some insight it would greatly appreciated. Thanks for reading

Oncoming_Offgoing Pressure.JPG

[gilgamesh]

I'm no expert by any stretch of the definition. But I was looking at your log and it sort of looks to me like the offgoing pressure for element B could be dragged out a little longer. I'm very interested in this topic. I hope someone with more experience chimes in.

You may find this post to be very relevant to your problem.
https://forum.hptuners.com/showthrea...-Ecoboost-6R80

I zoomed in and took a screenshot of your 3-4 shift for comparison.

Screen Shot 2018-03-08 at 9.00.17 PM.png

[veeefour]

post a tune

[Spooled]

I'm no expert by any stretch of the definition. But I was looking at your log and it sort of looks to me like the offgoing pressure for element B could be dragged out a little longer. I'm very interested in this topic. I hope someone with more experience chimes in.

You may find this post to be very relevant to your problem.
https://forum.hptuners.com/showthrea...-Ecoboost-6R80

I zoomed in and took a screenshot of your 3-4 shift for comparison.

Screen Shot 2018-03-08 at 9.00.17 PM.png

Thanks for this. I far from being an expert on this stuff. This trans stuff is complicated. I have referenced that thread you posted and tried to get an idea. I wasn't sure which element to adjust. Hell, I don't even know how you were able to get that graph from my log... I've been trying to figure out how to do that. Do the lines for the shift solenoids appear when you zoom in?

[CKrueg]

Looking at that log it looks like the boost pressure is applied to the oncoming clutch? i thought it was to the offgoing clutch?

[gilgamesh]

Looking at that log it looks like the boost pressure is applied to the oncoming clutch? i thought it was to the offgoing clutch?

I thought I had read that boost pressure was applied to offgoing clutch as well.


Spooled: Here's a post that describes the clutch sequence. This should help you with identifying which clutches are offgoing and oncoming for each gear change.
https://forum.hptuners.com/showthrea...l=1#post470905


Here's a link to the online help that shows the chart setup. https://www.hptuners.com/help/vcm_sc...lays_chart.htm It looks pretty out of date and lacking how you actually configure a group and series. Basically, you right click on the chart, go to 'charts layout', then create/modify the groups and series you want to display. You just need to create a group you want the parameters displayed in, add the parameters (aka series) you want in the chart, specify a min/max value and choose a line color. The toolbar along the top allow you to add/remove groups and series.

Screen Shot 2018-03-09 at 7.08.27 PM.png

[Spooled]

AWESOME AWESOME info. Thanks. Gonna mess with it tonight and try to get that 3-4 shift better.

[Spooled]

Alright I've tried to modify a couple things, but the shift doesn't look any different in the logs. Which table controls offgoing pressure/time for Clutch B?? I've tried messing with Element B boost time and the logs didn't look any different. What if I shortened the boost time for D clutch? Would that help as well?

[gilgamesh]

Alright I've tried to modify a couple things, but the shift doesn't look any different in the logs. Which table controls offgoing pressure/time for Clutch B?? I've tried messing with Element B boost time and the logs didn't look any different. What if I shortened the boost time for D clutch? Would that help as well?

Oncoming and offgoing pressure's are in the 'Auto Shift Properties' - 'Shift Pressures' tab. I'd probably try shortening the boost time for D at least to see how/if it affects the shift.

[gilgamesh]

I was just looking at your log again and I think I might actually see the boost pressure now in a way that fits Murfie's description of it being for holding the offgoing clutch. What do you think? Screen Shot 2018-03-10 at 2.10.02 PM.png

[Spooled]

Interesting. So increasing boost time could make that window longer that you have highlighted?

I made changes to Boost time for D already. Going to try that here shortly.

[Spooled]

I've made about 10 changes over the last hour and can't get the shift to look any different on the log. Gonna take a break and try again later with a fresh mind.

[CKrueg]

Yeah that could be. Then the boost pressure would be the pressure at which it holds, not actually an amount that it is incrrased.

[Lidio Iacobelli]

Spooled,

How many miles are on this car?

I'm starting to see some of the 2011+ coyote 6r80 cars come across now days with worn out 3rd gear clutch packs (element "B"). Causing a 3-4 flare, poor 2-3 upshifts, and weird down shifts that either end up in 3rd as the final commanded gear to downshift into, or touch/sequence into 3rd on they're way down to 2nd from 4th, 5th, or 6th.

I'm starting to see Power-Adder 5.0L (6r80) cars that have had very poor trans tuning (other shops or other tuners) or no trans tuning at all for the increase in power (boost, NOS), that eventually end up hurting the trans, with the 3rd clutch being the first to go most of the time. A lot of guys just wing-it and think "adaptive" will take care of it all !!

Hopefully its not mechanical and you'll catch it in the tuning. But I thought I'd suggest that as tuff as the 6r80 has turned out to be... they don't last long with out proper tuning and some TQ reduction still in there when well above stock power levels.

[Spooled]

I have 16,000 miles on it. It's been around 600hp for about 13,000 of those miles. Just recently turned the boost up after installing a return style fuel system.

I'm really hoping the clutch pack isn't worn out yet, but I'm ready to put clutches in it if necessary.

[CKrueg]

I've made about 10 changes over the last hour and can't get the shift to look any different on the log. Gonna take a break and try again later with a fresh mind.

What did you change exactly?

[Spooled]

I've messed with boost time (element B and D), boost pressure (Element B and D), Ramp Rate 3-4, Clutch Fill Time 3-4, Upshift pressure for offgoing and oncoming 3-4. I started messing with one table at a time then I tried boost time and pressure together and a couple of others. I was able to make it worse, but not better on several attempts.

[gilgamesh]

I've messed with boost time (element B and D), boost pressure (Element B and D), Ramp Rate 3-4, Clutch Fill Time 3-4, Upshift pressure for offgoing and oncoming 3-4. I started messing with one table at a time then I tried boost time and pressure together and a couple of others. I was able to make it worse, but not better on several attempts.

Would it make any sense that it might need need more oncoming and offgoing pressure due to the added power?

[Spooled]

3-4 shift screen shots from 3 vastly different tunes. The last one (7) actually felt the best but still flared.5.JPG6.JPG7.JPG

[gilgamesh]

it's a little hard to tell without seeing the actual values but it looks like in the last image the offgoing crossed the oncoming at a higher oncoming pressure than the other 2 images.