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Thanks for the update. What was your method for increasing line pressure? Looking for a way to do it, but so many mixed reviews on the resistors and their impact (CEL primarily)
 

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Discussion Starter #23
@Tweak3D I was able to raise line pressure using the calculated torque tables in the ECU. Based on logging, the TCU appears to match the value broadcast over CANBUS from the ECU to a torque vs pressure table. In the end this only slightly raised the peak line pressure, but the TCU ends up ramping to max line pressure at much lower loads which is still beneficial. The AWD clutch operates in a similar fashion- more calculated torque is more lockup.

Seeing you have a '17, it's worth pointing out I have literally no clue what happens if you mess with line pressure on a CVT. On an auto you're just increasing clamping force to the clutches. The CVT's line pressure goes to both pulley assemblies to control clamping force on the chain as well as the gear ratio by allowing the chain to ride up and down. Not sure if the specific pressure to each pulley matters, or simply the ratio of pressure between them. Cobb has probably done testing on this and may share their findings or at least indicate if their tunes adjust calculated torque.

Another unconfirmed report is that calculated torque must be raised with requested torque. The RomRaider thread had people chiming in that there are torque limiters in place that limit throttle response if the pedal requests less than the calculated output table.
 

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@NK2201 I actually also have an 05 4eat with the vtd and Sportshift swap performed. Ive been looking for line pressure adjustments and this info is helpful. Even a 10 or 15% increase is worthwhile. Do you have links to the romraider threads you referenced previously? Just curious for the details and I'll be upgrading my turbo and motor soon and needing a retune, so any info I can get would be helpful.
 

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Discussion Starter #25
@Tweak3D Wonderful, just making sure I put out the CVT disclaimer just in case... take a look at this thread over here http://www.romraider.com/forum/viewtopic.php?t=9358. These tables aren't part of the standard definitions pool so I defined them myself.

To do that, look at the images people posted of the tables and use the ScoobyRom software to scroll through all 3D tables in your ROM until you find ones that look the same. Instead of custom writing table definitions, in EcuFlash you can check the option in settings to show tables that are missing from your definition, and right click-edit the calculated torque table entry (Alpha DBW) and plug in the hex addresses. If the table doesn't look right flip the X and Y addresses until it matches. Do that for the remaining 3 calculated torque tables which should be identical. Do note that this method doesn't help you identify which is actually A,B,C,D but since they're seemingly all identical it doesn't matter, just set to them all to the same value when you edit. After that just go back through and verify that all four tables were defined and that you didn't accidentally define the same table twice or something.

There's still some speculation but the tables appear to match the actual torque output in NM for a reference EJ that may or may not actually be your engine's spec- looks like they through in "close enough" values. You could modify the tables to actually match your real output and torque curve, or do what I did and multiply the whole table by the multiple necessary to make the max value column hit 512.

And don't forget to raise requested torque in your DBW tables as well, which will also then require changes to the requested torque multiplier tables, and the target throttle tables, and the waste gate tables, and the target boost.... so basically the entire load target system needs to be adjusted. I can't recall if the 05 is DBW but if it's not it'll be a lot fewer tables to worry about.
 

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thank you for all that, this thread is super interesting and was not of a topic I'd have clicked just browsing. So currently I am tuned using an AP, but am getting a new tune soon. Do you by chance know if these tables exist in access tuner race? If not, i'm wondering if i'll need to do some back and forth between an open tune and an AP tune to catch these tables. I was just checking out scoobyrom, but seems its been discontinued and not seeing any download links still active. Do you know where the most recent version lives?
 
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