Modifying TCC line pressure.

[Joel_SS]

What is the best way to go about upping my line pressure for the TCC lock? I have a 2002 OS.. I saw the tabels for for TCC PWM (D2904 and D2903) but not quite sure how to change them, or what exactly they mean.

[SSpdDmon]

I changed D2902 to 850kPa, increased D2903 by 20%, and increased D2905 by 20%. This seemed to help the fact that the aftermarket converter I have has approximately ~20% less surface area on the clutch.

Although, I wish there was a better definition for "Slip RPM" in D2905. Then, I might be able to cure the lurch effect the car has when the TCC engages the drivetrain when it's spinning faster than the motor (ie RPMs are at 1500, TCC engages, RPMs shoot up to 2500 as the engine catches up and car slows down...like letting out the clutch at too low of an RPM in an M6). Right now, I have the first to rows in all of the TCC apply tables set to 256mph so the TCC shouldn't engage unless I'm giving it more than ~5% throttle.

[joecar]

Jeff,

How do the max and min tables work...?
I'm not too clear on these tables, I couldn't understand the very brief descriptions.

Joe

[SSpdDmon]

I made assumptions. I figured if the TCC could hold my friends torquer v.2 cam when I locked it on the dyno for a numbers run, then the max table is probably fine. Besides, my max table is pretty much maxed out at 95~98% already from the factory. I would guess that's 95~98% of the 850kPa number I mentioned above...but, that's just a guess. So, that basically leaves the min table and the apply rate. I just increased both of those by 20% because of the roughly 20% loss in friction area going from an 11inch converter to a 9 inch converter.

The other trick I like to do with the TCC is to set the release speeds so that when the converter is locked and I have the gear selector in drive (3), I can give it nearly 96% throttle before it unlocks (above 60mph). I guessed, with my 3.73s, this was roughly the point where my converter starts losing efficiency while unlocked. Now, I can almost floor it and have an A4 car that accelerates like an M6.

[Joel_SS]

In d2903 and d2904 what does the KPa refer to? Is that manifold pressure?

[SSpdDmon]

kPa is a metric unit of pressure. It's refering to line pressure in the trans in this case.

[joecar]

Also, I see the "shift" pressure tables, but I don't see any tables to set the "running" line pressure.