DCCD with Lateral G & Steering input

[west_minist]

Looking through the software, I noticed the Differential Control does not have the ability to use Lateral G and Steering Angle, but Traction control has it.

How can the DCCD be made intelligent through Syvecs?

[pavlo]

The S8 can use use those inputs through the TC strategy.

[TimH]

Does the S8 TC strategy include centre diff control?

[west_minist]

Pat,

Why the S8 and not the S6, since both have the features?

[west_minist]

Now I check, I don't see TC on the S8 Cal. I have.

[TimH]

This one I can help with, as I had to ask Pat just the other day.

There are flags set in the actual ECU that determine what features work, and TC is one of these. You either have to be connected to the ECU, or have a cal saved from an ECU that has the flags set.

[west_minist]

I figure that would be so.

I am totally interested in seeing how the TC connected stuff appears in the CD control.

[pavlo]

Okay now I've a bit more time and I've no doubt got you thinking...

First of all, if you just work with a cal and software because you haven't connected to an actual ECu yet, it will not have all the features enabled in the default cal. You will need a cal that was generated for an ECU with TC unlocked, which is just about all of them, if you try an upload a cal with TC (or DBW or Full knock or gear shift control) enabled to an ECU without those features it will either complain or just ignore. If you put your crafted cal without TC into a new ECU with TC enabled, when you next connect you will see the TC menu there with default options.

The TC strategy generates some combative action as follows:

Torque reduction = ((driven speed-vehicle speed)-slip target)*gain

Where slip target is define wrt RPM and (Lateral G OR Steering angle OR yaw rate) and can be tweaked via multiplication or addition in cal switch tables.
Gain is define wrt vehicle speed and cable tweaked via a multiplier in the cal switch tables.

Torque reduction (TcTrq) can be turned into a fuel cut and/or retard level via the cut tables in the TC strategy.

And this is where the diff control comes in, in the S8 there is an Diff duty added based on TcTrq, it only does anything when TcTrq is non zero. You can if you want run diff control duty only at TcTrq levels up to say 50% and then enable retard/cut on TcTrq levels from 50-100 (for example) or you can ignore the main TC element.

This can be used in a few ways:

Measure slip and add diff duty when slip is protected to try and stem the wheel spin.

Set negative slip target, increasingly negative wrt latG or steering angle. Increasingly negative slip values will generate increasing TcTrq values so you can use the Slip target maps to create a 3D overlay to add duty to your base diff control map.

Like always, the key to setting up is good datalogging and adding your parameters of interest to your Scfg files.

[west_minist]

That means if you have TcTrq over a certain value and increasing, you apply TC.

Pat, that means you must have a S8?

Any reason why the S6 doesn't have it?

Can you email me the cal.

I am trying to get the s6 next year for my 2000 GC8 with a STI 5MT DCCD RA Tranny.

west_minist@xtremeracingtuning.com