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TwinTurbo · 08-26-2005, 02:24 AM

The ESC is not the metal cased box behind the glove box, the ESC has a black plastic case and is usually mounted on the back of the ECM, the metal cased box is an ECM, a very early and crude one but it is, it even has a 122XXXX number that all the early original ECMs have (for instance later trucks w/ tbi use 1227747...don't remember the # on mine)

If you have an ESC knock controller you also have an ECM as the ESC always reports knock to th ECM, which in turn registers the knock counts and signals the EST (module in distr) to puyll back timing in 7 deg. steps untill no knock counts are registered. The box used w./ the electronically controlled quadrajet on the 305 IS an ECM, even though it does not directly meter the fuel delivery it does adjust the primary metering rods

08-26-2005, 02:24 AM	#24
TwinTurbo Registered User Join Date: Sep 2003 Location: The Netherlands Posts: 994	The ESC is not the metal cased box behind the glove box, the ESC has a black plastic case and is usually mounted on the back of the ECM, the metal cased box is an ECM, a very early and crude one but it is, it even has a 122XXXX number that all the early original ECMs have (for instance later trucks w/ tbi use 1227747...don't remember the # on mine) If you have an ESC knock controller you also have an ECM as the ESC always reports knock to th ECM, which in turn registers the knock counts and signals the EST (module in distr) to puyll back timing in 7 deg. steps untill no knock counts are registered. The box used w./ the electronically controlled quadrajet on the 305 IS an ECM, even though it does not directly meter the fuel delivery it does adjust the primary metering rods Last edited by TwinTurbo; 08-26-2005 at 03:00 AM.