Ok guys, Has anyone experienced an ECU upgrade on their 2.3 yet? I'd really like to eliminate this terrible throttle response. Has anyone taken apart the ECU module? Is there a discrete flash prom? Is it soldered or socketed? I know that it is flash upgradable, but I'd hate to risk failing smog inspection in San Diego because someone mapped a portion of the curve too rich. I'd prefer the old switched daughterboard solutions that some companies offered several years ago. You mounted a second chip, and switched between them when your ignition was off. The new M3 has an ECU sport switch which restores much of the engine's throttle response. I want this feature on my Double Vanos 2.5 L 6. Can anyone help?