Hows this for a complex problem!!

[robbo_yobbo]

The following all came after an upgrade to an xr6vct engine and manual conversion to an AU1 forte.........

Originaly the car was blowing a tonne of black smoke and averaging 200kms or less to a tank of petty (engine was fine, not using oil or coolant, leads plugs coilpack fuel pump and regulator all fine injectors were all fine, oxy sensor rooted but replaced Map sensor fine also and the whole exhaust was done just incase there was a blockage, but none of this solved the problem!).

all of a sudden this stopped one day but instead, when I put my foot to the floor so as to achieve a WOT status - the injectors shut down, and somehow the timing is out now too, as the power peaks around 2 1/2-3gran resulting in a gutless car (it had plenty of power when blowing smoke!).
after weeks and weeks now of trying to get a diagnosis there is finaly a theory!!
theres a fault code showing up for the vehicle speed sensor (however the sensor has been tested as fine and no probs with speedo either).
As my Forte is a late model series 1(jan 00) it uses the series 2 smartshield imobiliser system instead of the series 1 one, thus not allowing a series 1 ECU to be used so a series 2 ECU has been running the car since the conversion.
It is assumed that because my cars BEM is a series1/2 hybrid but the ECU is a S2 they are not speaking to eachother properly, and that for some reason the ECU is missinterpretting the WOT signal for a speed signal of 240kmph + thus activating the speed limiter and shutting off the injectors!!

COMPLICATED?? YES!

Solution: Ill be changing over the dash BEM and wiring looms to a earlier series 1 and using the same ECU to match and hopefully this solves the problem of the injectors and of the ignition timing also......

anyone else had any dramas like this?
if it doesnt solve the issues, any ideas how to fix it or any other theorys, every mechanic ive been to is stumped and im frustrated as hell!!!??????