How to Tune 5EAT Line Pressure

[seabass07]

I wonder if we could hook up a resistor to the AT temp sensor and get it to read a constant temp. Or maybe just connect it to an external temp sensor so it reads ambient temps. That would increase line pressure all around.

 

I'm not sure how we can figure out how it weighs the RT vs RPM. The vacation pix say that line pressure increases with RPM. It also increases with requested torque. But the requested torque decreases with RPM when the throttle is steady.

[Deadleave]

Has anyone logged with rescaled RT, and seen if any boost changes occurred ? ie overboost ?

 

Also if editing these values, are baseline value same for everyone ? If I need to go back to stock for these values, but not the tune.

[seabass07]

I'm wondering whether this effects the D and sport shift points. It looks like it does make decisions about when to shift from that table. ClimberD have you noticed any difference in that?

[seabass07]

Has anyone logged with rescaled RT, and seen if any boost changes occurred ? ie overboost ?

 

Also if editing these values, are baseline value same for everyone ? If I need to go back to stock for these values, but not the tune.

 

 

I'm going to do that in a couple of hours.

 

I think stock they are the same, but some tuners mess with the values. Just backup the original read rom and save the modified one as something else so all you have to do is flash back the original. For some reason, romraider is not letting me paste in the stock table after it was modified.

[underground000]

*Deleted

[ClimberDHexMods]

For the record: I am very busy with a big acquisition at work. I also have fuel lines to swap and a new boost solenoid to wire in. My tune isn't even done yet. I cannot do ANYTHING more for this thread or topic right now.

 

Once I have the opportunity, I will be all over it!

[fishbone]

underground, any changes in shifting behavior?

[underground000]

*Deleted

[seabass07]

I definitely noticed a difference. It is not major, but it shifts with conviction now. Its really noticeable in mid RPM shifts 3 or 4k. At WOT if feels slightly faster. I did notice while in D some slight hard shifts while driving slowly. It wasn't a bang into gear or anything uncomfortable, just more than before. Now to tune it. We need less RT down low and more up top. It's just populating the throttle table with those values that I'm not sure about.

 

I haven't checked for overboost all over yet, but my peak boost was exactly the same. Maybe .5 up from before, but still under my target by a small amount. It went up to 13.5.

[ClimberDHexMods]

I definitely noticed a difference. It is not major, but it shifts with conviction now. Its really noticeable in mid RPM shifts 3 or 4k. At WOT if feels slightly faster. I did notice while in D some slight hard shifts while driving slowly. It wasn't a bang into gear or anything uncomfortable, just more than before. Now to tune it. We need less RT down low and more up top. It's just populating the throttle table with those values that I'm not sure about.

 

I haven't checked for overboost all over yet, but my peak boost was exactly the same. Maybe .5 up from before, but still under my target by a small amount. It went up to 13.5.

 

I think the easiest way is to adjust a column at a time, and that way you can carry over the change to the associated TP column header.

[seabass07]

They just need to be mapped out. They contain different points on the same map. Not too difficult, I just suck at excell now. I have to relearn it.

[ClimberDHexMods]

Here are the RT map tweeks I am going to try later before I go any further. They make sense considering where we want there to be more line pressure. I like everything nice and linear when it can be. I realize the TP map is a mess too, but that is a whole other ball game involving actual math and a lot more guessing.

http://legacygt.com/forums/showpost.php?p=2741976&postcount=193

 

http://legacygt.com/forums/showpost.php?p=2742142&postcount=198

[seabass07]

The TP map should be as simple and tedious as maping out all of the values in the RT table and seeing where the TP values fall on that map. I can't do any 3d mapping on my laptop so I'll have to put everything on my other computer. But I'm thinking that we have more leeway than we think with the TP. The stock TP map is just close to the RT.

[underground000]

Forget all this, its too complicated and might not even work!!! Its taking too long!!!!!

Just throw on a resistor and make sure the CEL light comes on and youll be at max line pressure, system will be normal not limp mode. Youll just lose 5th gear but its ok 4th gear is 1:1

:spin::spin::spin::spin:

[seabass07]

It's not that bad. It will just change throttle response if not perfect (I think). Just increasing everything by 40% definitely changed throttle response for me, in the same way sport changes it from D, just even more. Driving normally, it's a little more touchy. Personally, I like it.

[fahr_side]

Just to be pedantic, I want to remind everyone that the requested torque values are just raw ECU values. There are no units attached to them, like lb/ft or Nm... Even on stock maps they don't seem to correspond to the measured or claimed torque outputs of the cars.

[underground000]

Just quoting what Cobb Tuning says

"Throttle Requested Torque (A,B,C)

Table Description – This is a table that defines requested torque in newton meters as a function of throttle

position and engine speed."

[utc_pyro]

Forget all this, its too complicated and might not even work!!! Its taking too long!!!!!

Just throw on a resistor and make sure the CEL light comes on and youll be at max line pressure, system will be normal not limp mode. Youll just lose 5th gear but its ok 4th gear is 1:1

:spin::spin::spin::spin:

 

You might as well just disconnect the line to the pressure regulator solenoid them. full pressure FTW!

[seabass07]

The value could be related to the amount of torque at engagement. It would be a sudden jolt of torque much higher than actual output.

[ClimberDHexMods]

NO!!! The RomRaider devs just converted the raw values to something tuners can make sense of instead of .00943687 or whatever number the ECU produces. They change that 87692.873 or whatever to "300" so you don't go crazy. When you type in new RT numbers, RomRaider converts them back to raw value then writes it to the ECU.

 

 

Raw ECU values can be telling, like for figuring out injector scaling and latency a little bit better.

 

Perhaps there is something of value in the raw ECU values, or it is all just arbitrary?

[utc_pyro]

I think the "requested torque" is infact a raw value the ECU uses. Does it represnet some sort of real number? Maybe, maybe not. The best way to tell is to look at the stock ROM's from a few diffrent cars (NA Legacy, STI, GT, WRX, ect) and see if the "peek" value changes between them. If so, and it's perportional to the max torque that motor produces, then it represnets actual torque. Other wise, it's just a scaler used to map between the throlle maps.

[ean611]

I definitely have to look into this. Good info here. Going to talk to my tuner about a session.

[fahr_side]

I think the "requested torque" is infact a raw value the ECU uses. Does it represnet some sort of real number? Maybe, maybe not. The best way to tell is to look at the stock ROM's from a few diffrent cars (NA Legacy, STI, GT, WRX, ect) and see if the "peek" value changes between them. If so, and it's perportional to the max torque that motor produces, then it represnets actual torque. Other wise, it's just a scaler used to map between the throlle maps.

The RT number is different between cars with different torque outputs, and always higher on cars with higher output. However, it isn't a direct match to Nm or lb/ft.

[utc_pyro]

The RT number is different between cars with different torque outputs, and always higher on cars with higher output. However, it isn't a direct match to Nm or lb/ft.

 

Is it perportional? One could estimate the torque output based on the load (g/rev), so it might play into some sort of usefull calculation.

 

If that's true, we should bump this up anyway as we are making more torque.

[ClimberDHexMods]

Would be great to have a quick and dirty system to match RT colums and TP header values to turbos, but I can't figure how since the RT table changes by accelerator angle, not RPM. If anything, it would be better to make all the values in any column the same, or even high RPM-biased, which is the opposite of what we get now. We also don't know how mph affects the line pressure solenoid duty cycle calculation...