If it was the car that you were in, the garage editor has a bit of a spaz attack and doesn't save it. Try swapping to another car, then saving the game, open the save in the Garage Editor, find your Focus in the Garage tab (if it is the last Ford you bought, it will be at the botom of the Ford list), then change the multiplier in the tuning sheet. Save it, copy it onto your PS3, change into it and you should have a bit more power. Also, the power multiplier isn't actually that accurate, so if you did want 8x power, try 13 or 12

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