I have been working with TurboLamik, for the last several month, on having full integration between the Holley EFI systems and the TurboLamik TCU. What this means is that the two will be connected with just 2 wires. This applies to the Holley Dominator and HP using V6 and also to Terminator X and X Max using V3. The Dominator and Terminator X Max are optimal because they have two CAN busses and DBW throttle.
The TCU needs information in order to make shifting decisions. Namely, it needs RPM, TPS, MAP, and torque output. Those are the basic channels that are a must, however, in order to make the transmission work optimally, the TCU needs to send messages back to the ECU.
The most critical is a signal to retard the timing during upshifts. This is commonly known as torque management and all modern transmissions implement this strategy, both for smooth shifting as well as transmission longevity. It can also be extremely helpful to retard the ignition during shifts to keep the tires from spinning during hard upshifts. With a very powerful engine, it can actually be pretty dangerous to upset the car during a full throttle upshift. This feature is now working between the TCU and the Holley ECU.
Another feature that goes along with torque management is throttle blipping on downshifts. This feature isn't strictly necessary, but it too will be available, although somewhat limited, because Holley...
The TCU will also send the following information: Gear, transmission temperature, speed, converter slip, and clutch slip. All of this information will be available to be displayed on any of the Holley digital dashes, not including the 3.5" handheld.
If there are any questions, please ask.
Andrew