Originally Posted by markk

Diesel torque converter does not suit revvy petrol engines.

Yes they need to be torque controlled and closed loop. I first converted mine with just rpm\tps based open loop but it was not good enough for a road car.
Now I'm on a torque model closed loop.
If you need to change engine ecu find one that is already integrated and proven with a gearbox ECU. Can still be external to the engine ecu, just find one that all the integration work has been proven out or you will soon get fed up of getting to the point of acceptable operation.
I can't comment for any other controller other that HTG GCU.