Are you sure about the Mondeo ECU?, IIRC Madmole has a custom burned chip, I would be pretty sure that any chip would involve tweeking the timing. Besides switching heads or shaving the block; JE pistons, BAT, Burton Power, and (I think) Need for speed, sell piston sets that would up your Comp. Ratio.
EDIT: I left one company out, Dunnel Engines also makes piston for the Zetec.
