Tool to help tune A4 shift points...
Well...spreadsheet. Here ya go. Now you can visually see the upshifts next to the downshifts and the TCC applies/releases next to each other without having to flip between multiple tables in the software. It's pre-filled with the numbers I'm going to try in my friend's A4 F-body (4.10's) this weekend.
What to do with it:
Start with your upshifts and downshifts before playing with the TCC apply/releases. First off, copy/paste (no labels) your Normal, Part Throttle vs. VSS upshifts/downshifts/TCC Apply/TCC Release columns into the appropriate columns on the left side of the spreadsheet.
We'll start with the first graph (Shifts). What you're looking at is upshifts represented by solid lines and downshifts by hashed/dotted lines. I tried to color code it so the upshift is slightly darker than the downshift (i.e. 3>4 is red and 4>3 is orange) - it helps a little visually. Anyway, ideally you want to keep your upshifts greater than your downshifts between a given set of gears. Personally, I like to keep the downshift slightly higher than the previous gear change's upshift. So, the general rule for this graph is:
(2-to-1)<(1-to-2)<(3-to-2)<(2-to-3)<(4-to-3)<(3-to-4)
The next two graphs help you to see where the TCC will apply and release in relation to the shifts that can affect it. The first one (TCC 3rd Gear) is a little tricky because sometimes people cruise around in D instead of (D). Here you want your TCC apply to be greater than or equal to your upshift AND greater than your TCC release. Technically the PCM will command the TCC to release for a downshift, but I like to keep the TCC release slightly higher than the downshift. That way, if a downshift is commanded, the TCC is already disengaged. It also serves to let the converter 'work' in certain scenarios. For example, say the car is slowing down going up a hill even though you're giving it 25% throttle. The TCC will release and you can make use of the toqure multiplication of the stall before it'll downshift into the lower gear. So, the general rule for this graph is:
(3-to-2)<(3rd Rel.)<(3rd App.) AND (2-to-3)<(3rd App.)
Another thing to note...when cars have a loose aftermarket stall, it's a good idea to max out the first two TP% rows to prevent what I call inverted lockup. This is when the engine speed is spinning slower than the drivetrain and the TCC decides to lockup. When this happens, it feels like you went to hit the gas and found the brake pedal instead.
The next graph (TCC 4th Gear) works just like the previous one. The rule here is:
(4-to-3)<(4th Rel.)<(4th App.) AND (3-to-4)<(4th App.)
Again, note the first two rows being maxed out to prevent inverted lockup.
The final graph (TCC - 3rd & 4th) is there for further visualization, but it wasn't really necessary as 3rd & 4th TCC apply/release technically have nothing to do with each other.
Hope that helps some...
The nice thing is, you can set this up for a few cars and then "Save as" Trans-3.73s or whatever. Then...before you know it, you'll have a worksheet for most any combination. That way, when the next car rolls in, all you have to do is copy over the numbers from the right spreadsheet.
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