Mitsubishi Lancer Evolution Forum banner

1 - 20 of 63 Posts
Joined
·
5,198 Posts
Discussion Starter #1
I've been pretty quiet lately. I've been trying to iron out some issues on my personal SST equipped Mitsubishi. You can see more about this car here:

http://forums.evolutionm.net/09-ralliart-engine-turbo-drivetrain/483013-project-2010-ralliart-sportback.html

I've been chasing some SST "issues" that have came up on this car now that it's making a good amount of power. To be frank, it's been maddening and I've probably developed more gray hair since then. :crap::lol:

Some of that frustration comes from myself because I can't leave good enough alone, I wanted more power then normal out of the car and I've been tinkering with a bunch of SST stuff, with help from some people that are very talented in ECU Disassembly, etc. I'm also doing this to help other owners of SST cars, so when they encounter the same issues, hopefully there will be answers.

The point to this post is that things are still moving forward. The SST is a hugely complicated thing and even more complicated in code. It's actually mind blowing in the sheer amount of tables associated with other tables, associated with other tables and then even more... {pcfreak}

I teaser of a small amount of new discoveries are here in this screenshot of a log of my RA in 2nd and 3rd gear, WOT. Things like this excite me, even if they seem not so interesting to others. I am just weird that way... ;)

 

·
Registered
Joined
·
8,577 Posts
AMAZING Work Bryan this is very very exciting!!

Just a quick question why is the pressure on the Even clutches to progressive at the start, if this was a 2nd to 3rd pull wouldn't you see the same type of pressure as the odd just at the 2nd gear area? Or were you already rolling in 2nd and then got on it? even at that I'm surprised it took so long to build up pressure.

Still though great work finding these tables this is great info!!

Were you in Sport in Manual? Just asking based on the shift points wish look more like SSport for Auto ;) But since it's an RA trans I'm guessing you went manual for it?

Those torque tables look like they could be very useful :>
 

·
Registered
Joined
·
1,624 Posts
maybe a quick sentence or 2 for those of us who dont know what we're looking at?
 

·
Registered
Joined
·
8,577 Posts
looking at lots of very important tables/numbers that the TCU/ECU use for calculations, those Torque tables for example are likely how the TCU knows to open the clutches. If one could change the scale of those tables one could trick the TCU into keeping pressure on the clutches. This is just an example, basically he is showing that they are finding the data that we will need, reverse engineering software of this nature is a timely and sometimes trial and error procedure, so little steps really are big steps.

I'm with Bryan on this one, this is very exciting graphs for anyone with an SST that wants to try and get past some of our higher power issues.

I find it most interesting to see how the actually torque and the torque lookups are not mirrored, in fact they are almost opposites to a degree, when one deeps the other is rising. That is pretty interesting I wouldn't have guessed that, makes me wonder how the lookup is calculated. The lookup matches RPMs more then torque....
 
Joined
·
5,198 Posts
Discussion Starter #6
Just a quick question why is the pressure on the Even clutches to progressive at the start, if this was a 2nd to 3rd pull wouldn't you see the same type of pressure as the odd just at the 2nd gear area? Or were you already rolling in 2nd and then got on it? even at that I'm surprised it took so long to build up pressure.
Clutch pressures seem to increase in each gear. Example: 150psi in 2nd, 172psi in 3rdm 188psi in 4th. At certain boost pressure my 2nd gear ends up pretty much useless and more gray hairs appear on my head.

Were you in Sport in Manual? Just asking based on the shift points wish look more like SSport for Auto ;) But since it's an RA trans I'm guessing you went manual for it?
It's in Manual Sport, I just wasn't revving it all the way out.

I find it most interesting to see how the actually torque and the torque lookups are not mirrored, in fact they are almost opposites to a degree, when one deeps the other is rising. That is pretty interesting I wouldn't have guessed that, makes me wonder how the lookup is calculated. The lookup matches RPMs more then torque....
The TorqueLookUp is logging output from a specific table, so it's just spitting out the numbers in those table, which happen to increase in RPM, as you can see in the log.

We believe Torque (Nm) is calculated torque in Newton Meters. 516 Nm = 380 ft/lb. 465 Nm = 343 lb/ft
 

·
Registered
Joined
·
8,577 Posts
so boost pressure is a suspect to have some sort of effect on the calculation along with RPM? We always knew that around 28psi clutches open up with the factory protection in tack. so it would make sense that it's a base of some of the calculations.

So the lookup table maybe not be torque it's just the name that you guys picked for it for now?

That torque table looks pretty dead on to me and nm seems like what would be used there for sure. It's very interesting to see these values plotted out like this though, it seems that lookup table not only follows RPMs but gear shifts which might be the pressure cut for shifting? Seem to match up, but I'm trying to figure out a calculation that would make sense. Like (RPM/1000) * boost * gear or something, though the +gear would mess things up and you'd see it rise much higher. I'm sure MAF calculated LOAD is involved and would explain why a bad MAF messes with the SST so much.

Looking at it I bet I could figure out a relation between RPM and load to get that lookup table. Actually drop load, lookup looks like RPM / 100
 
Joined
·
5,198 Posts
Discussion Starter #9 (Edited)
so boost pressure is a suspect to have some sort of effect on the calculation along with RPM?
It does but not what I meant by my statement. I mean with more boost the car makes more torque and 2nd gear just slips and becomes useless. One of the big problems I have with my RA is that Sport mode doesn't give enough clutch pressure for my power level now. S-Sport would be a nice thing to have as it further increases pressure over Sport.

My 1st gear was useless awhile ago. If I run the same boost in 1st as my other gears (26psi) then the car will not shift. I'm currently running 20psi in 1st and some forced throttle closure at 6500+ RPM and even then it get's a little finicky sometimes.

So the lookup table maybe not be torque it's just the name that you guys picked for it for now?
It's a torque lookup table. It's just one of many used in calculations of other things.

That torque table looks pretty dead on to me and nm seems like what would be used there for sure.
Yea 380ft/lbs at the motor sounds about right for my car as it currently sits, however it peaks at 516 Nm pretty early in the WOT pull so I'm not sure this is 100% what we think it is yet.

It's very interesting to see these values plotted out like this though, it seems that lookup table not only follows RPMs but gear shifts which might be the pressure cut for shifting?
The table it's referencing is a simple RPM x Value table so it follows RPM.
 

·
Registered
Joined
·
8,577 Posts
sorry for all my posts but I love this stuff and have been waiting for someone to post these findings.

obviously I'm just guessing as I don't have any of the background or knowledge you do. But I hope that me just trying to find patterns might burt something stupid out that might be like "oh look at that..."

if it possible that the lookup table is passing a value to the SST to do it's own torque calculation?

sure would be nice to be able to use 6th pressure through out the gears... since you guys have the pressure tables, have we found anything that affects them yet? Other then gear of course? Something we can modify or intercept? I was thinking about making a breakout board between the ECU and TCU, something to enable probing and injection from, but since most of it is likely encoded through canbus and it seems you software guys are making progress I didn't see the point in such a crude method.
 
Joined
·
5,198 Posts
Discussion Starter #11
the pressure tables, have we found anything that affects them yet? Other then gear of course? Something we can modify or intercept?
I was able to increase pressure one way a couple months ago:



Red solid (clutch pressure) and dotted (clutch slip) plots are before. Blue solid and dotted plots are after. However it had the huge drawback that it would "rev hang" horribly on shifts for some reason that I have not figured out why yet. I think it might be clutch drag but I'm not 100% on that.

You can see the rev hang here, red is before, blue is after:



The good news is these are all good forward movements, even if it makes me get gray hairs. ;)
 

·
Registered
Joined
·
8,577 Posts
well based on that info I'm guessing if we add pressure to the packs we need a way to remove it on shift.

ie if it's 185psi in gear and should be 150psi, I bet on shift it's keeping that extra 25psi. I wondering if there is a table someplace that is between gears and has a negative psi or even a psi that is taken in negative, maybe even on the same graph, ie since there is even and odd (obviously different packs) there needs to be tables but what if when that table isn't in gear we need to remove more pressure to compensate for adding pressure to the other side? That make sense? Just seems like if you add pressure and then it won't release. Maybe it can't bleed pressure fast enough?

Now I want to see the veins in the valve body between gears see if they vary in size :\
 

·
Registered
Joined
·
678 Posts
Great info! Thanks for posting this up Bryan.

I've got a newb question for you. I'm in the tuning process right now and I have no idea how to tell if the clutches are slipping. Is it something that is quite noticable? Is there any way I can log clutch slip with ATR? Right now VD has me at 375HP/375TQ with peak torque at 3700! Still a lot of tuning to go ;)
 
Joined
·
5,198 Posts
Discussion Starter #14
Great info! Thanks for posting this up Bryan.

I've got a newb question for you. I'm in the tuning process right now and I have no idea how to tell if the clutches are slipping. Is it something that is quite noticable? Is there any way I can log clutch slip with ATR? Right now VD has me at 375HP/375TQ with peak torque at 3700! Still a lot of tuning to go ;)
You can see it in the RPM plot. If it isn't linear straight then the clutches are slipping.

Like this:

 

·
Registered
Joined
·
1,401 Posts
Bryan, does this relate to the 'issue' i'm having with my car when shifting from 1st into 2nd? With moderate to heavy throttle, the car shifts into 2nd sluggishly and feels like there is some slipping before the gear engages. It feels almost like a traditional automatic/torque converter type of shift
 

·
Registered
Joined
·
8,577 Posts
Bryan I can only assume you have an SST temp gauge or that you can set a graph to the SST temp.

I'd love to see these graphs vs temp, ie the same pulls at 100-120F, 160F and 180+F, specifically the pressure graphs. I have been curious about this for some time and I think there might be a temp correction table some place.
 
Joined
·
5,198 Posts
Discussion Starter #18
Bryan I can only assume you have an SST temp gauge or that you can set a graph to the SST temp.

I'd love to see these graphs vs temp, ie the same pulls at 100-120F, 160F and 180+F, specifically the pressure graphs. I have been curious about this for some time and I think there might be a temp correction table some place.
Like this?

 

·
Registered
Joined
·
3,979 Posts
A few uneducated thoughts:

-Why CAN'T you make clutch pressure the same across the board?
-If changing the pressure leads to shifting problems, that tells ME that there is a master table that hasn't been found, and when the two cross reference there is a difference that leads to a "sticky" gear change
-Is it true, then, that the issues with the SST seem to be heat and software only? The heat issues seem to be easily solved with trans cooler etc; it seems like you're trying to make the tranny better for higher power levels, which could do two things: put serious pressure on the trans coolers abilities since they are working harder, and also test the MECHANICAL limitations (which as yet haven't seem to have been the problem).

Again these are my uneducated thoughts, just trying to learn as I go. I wonder what the norm will be when I go to mod my car....I just want basic bolt ons, decent tune and RELIABILITY. If I can improve on inefficiencies and make it quicker just by messing with the SST then I'm a happy man. :D
 
1 - 20 of 63 Posts
Top