Your tune will now be off (rich) because the fuel pressure will be higher above 3000 rpm (ish) now the pump is running on 12volts when it should be.

Your tuner is a dick if he couldn't pick it running out of fuel volume and the associated high injector duty cycle on a stock car.

They are simply a pulse width modulated motor speed controller, the heatsink keeps the switching Fets cool.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]