Have you thought about converting to a mechanical throttle Derek?
I am looking in to this. Although the throttle function is integrated in to the ECU, I think the system is reasonably independent. i.e. the system only controls the function of the motor controlling the throttle butterfly. The actual fueling/ignition uses the MAF, IAT etc. i.e. the engine runs in response to throttle butterfly movement irrespective of what moved it. I'll let you know what I discover. If you are struggling to get the widget that Xfire1 posted, its something that can be built fairly simply with a small processor board programmed to give any relationship between pedal and throttle angle ($20 worth really) Whether or not the engine will respond to a more rapidly opening throttle is another matter though. It would be fun to have a play with something to find out though.